Publications by year
In Press
Jones M, Aragão LEOC, Dittmar T, Rezende CE, Almeida MG, Johnson BT, Marques JSJ, Niggemann J, Rangel TP, Quine TA, et al (In Press). Environmental Controls on the Riverine Export of Dissolved Black Carbon.
Global Biogeochemical CyclesAbstract:
Environmental Controls on the Riverine Export of Dissolved Black Carbon
Each year, tropical rivers export a dissolved organic carbon (DOC) flux to the global oceans that is equivalent to ~4% of the global land sink for atmospheric CO¬2. Among the most refractory fractions of terrigenous DOC is dissolved black carbon (DBC), which constitutes ~10% of the total flux and derives from the charcoal and soot (aerosol) produced during biomass burning and fossil fuel combustion. Black carbon (BC) has disproportionate storage potential in oceanic pools and thus its export has implications for the fate and residence time of terrigenous organic carbon (OC). In contrast to bulk DOC, there is limited knowledge of the environmental factors that control riverine fluxes of DBC. We thus completed a comprehensive assessment of the factors controlling DBC export in tropical rivers with catchments distributed across environmental gradients of hydrology, topography, climate and soil properties. Generalised linear models explained 70% and 64% of the observed variance in DOC and DBC concentrations, respectively. DOC and DBC concentrations displayed coupled responses to the dominant factors controlling their riverine export (soil moisture; catchment slope, and; catchment stocks of OC or BC, respectively) but varied divergently across gradients of temperature and soil properties. DBC concentrations also varied strongly with aerosol BC deposition rate, indicating further potential for deviation of DBC fluxes from those of DOC due to secondary inputs of DBC from this unmatched source. Overall, this study identifies the specific drivers of BC dynamics in river catchments and fundamentally enhances our understanding of refractory DOC export to the global oceans.
Abstract.
Glendell M, Macshane G, Farrow L, Quinton J, Anderson K, Evans M, Benaud P, Rawlins B, Morgan D, Jones L, et al (In Press). Testing the utility of structure from motion photogrammetry reconstructions using small unmanned aerial vehicles and ground photography to estimate the extent of upland soil erosion. Earth Surface Processes and Landforms
2023
Naylor LA, Dungait JAJ, Zheng Y, Buckerfield S, Green SM, Oliver DM, Liu H, Peng J, Tu C, Zhang GL, et al (2023). Achieving Sustainable Earth Futures in the Anthropocene by Including Local Communities in Critical Zone Science.
Earth's Future,
11(9).
Abstract:
Achieving Sustainable Earth Futures in the Anthropocene by Including Local Communities in Critical Zone Science
Critical Zone Science (CZS) explores the deep evolution of landscapes from the base of the groundwater or the saprolite-rock interface to the top of vegetation, the zone that supports all terrestrial life. Here we propose a framework for CZS to evolve further as a discipline, building on 1st generation CZOs in natural systems and 2nd generation CZOs in human-modified systems, to incorporate human behaviour for more holistic understanding in a 3rd generation of CZOs. This concept was tested in the China-UK CZO programme (2016–2020) that established four CZOs across China on different lithologies. Beyond conventional CZO insights into soil resources, biogeochemical cycling and hydrology across scales, surveys of farmers and local government officials led to insights into human-environment interactions and key pressures affecting the socio-economic livelihoods of local farmers. These learnings combined with the CZS data identified knowledge exchange (KE) opportunities to unravel diverse factors within the Land-Water-Food Nexus, that could directly improve local livelihoods and environmental conditions, such as reduction in fertilizer use, contributing toward Sustainable Development Goals (SDGs) and environmental policies. Through two-way local KE, the local cultural context and socio-economic considerations were more readily apparent alongside the environmental rationale for policy and local action to improve the sustainability of farming practices. Seeking solutions to understand and remediate CZ degradation caused by human-decision making requires the co-design of CZS that foregrounds human behavior and the opinions of those living in human modified CZOs. We show how a new transdisciplinary CZO approach for sustainable Earth futures can improve alignment of research with the practical needs of communities in stressed environments and their governments, supporting social-ecological and planetary health research agendas and improving capacity to achieve SDGs.
Abstract.
Hong S, Cong N, Ding J, Piao S, Liu L, Peñuelas J, Chen A, Quine TA, Zeng H, Houlton BZ, et al (2023). Effects of Afforestation on Soil Carbon and Nitrogen Accumulation Depend on Initial Soil Nitrogen Status.
Global Biogeochemical Cycles,
37(1).
Abstract:
Effects of Afforestation on Soil Carbon and Nitrogen Accumulation Depend on Initial Soil Nitrogen Status
AbstractLong‐term carbon (C) sequestration in terrestrial vegetation and soil is mediated by soil nitrogen (N) supply. Afforestation is regarded as a global‐scale solution to climate change; thus, resolving the role of N in either facilitating or reducing the long‐term C benefits of this practice has essential implications to maximize its C sink potential. The impacts of afforestation on soil C, N, and their stoichiometric ratio have been widely explored but what regulates these impacts remains unclear at regional and global scales. In this study, we conducted an intensive field sampling investigation including 610 pairs of afforested and control plots in northern China and extensively compiled a global data set containing 211 afforested‐control pairs worldwide to evaluate responses of soil N concentrations and C:N ratios to afforestation and further explored their major regulator. We identified a soil N threshold, the inflection point where afforestation changes from increasing to decreasing soil C and N, which was 0.86 (95% CI: 0.81–0.91) kg N m−2 in 0–1 m depth. Changes in soil C:N ratios with afforestation were mediated by initial relative abundance of soil C and N and types of mycorrhiza associated with planted trees. Increases in soil C:N were mostly driven by trees with ectomycorrhizal associations but did not change for those associated with arbuscular mycorrhizal fungi. These results provide a data‐based understanding on soil C and N dynamics following afforestation and its underlying mechanisms and further highlight the importance of site selection based on initial soil properties in future afforestation.
Abstract.
Liang B, Liu H, Wang S, Cressey EL, Dahlsjö CAL, Xu C, Wang J, Wang Z, Liu F, Feng S, et al (2023). Model bias in calculating factor importance of climate on vegetation growth.
Global and Planetary Change,
228Abstract:
Model bias in calculating factor importance of climate on vegetation growth
Machine learning is increasingly used to study vegetation growth, however, more often than not, predicting and simulating functions are prioritized over quantitative estimates of the drivers of vegetation growth such as climate. In this paper, we, for the first time, systematically investigate the model bias in calculating factor importance of climate on vegetation growth, especially when various kinds of machine learning models are considered. We undertake two case studies to simulate research in remote sensing and ground-based scenarios from which the difference in quantitative relationships between climate and vegetation is evaluated across multiple models. We found that model complexity increased the determination coefficient (R2) but reduced the absolute importance of the preselected independent variables. As the fitting accuracy increases, the absolute factor importance of dominant factor and all the other influencing factors decreases simultaneously, and factor importance calculated by different models tended to be more normally distributed across the study region. The reduction in factor importance was accompanied by the increased effect of model selection; e.g. the model that was used to estimate vegetation growth played a larger role in producing the factor importance (shown by variance analysis, remote sensing scenario, F-statistic = 555.2; ground based scenario, F-statistic = 30.8) than the climate variables (variance analysis, remote sensing scenario, F = 460.8; ground based scenario, F = 28.8). Critically, for those machine learning models with highest fitting accuracy, the resultant factor importance of climate factors had smaller difference with that of random factor. In contrast, the relative factor influence among the selected climate factor is more robust and reliable (in variation analysis, model was detected no significant impact on the resultant factor importance). For 5 of 8 models, the dominant factor (temperature) has relative influence over 0.85, ranging from 0.88 to 0.99. According to the relevant result, we suggest testing the stability of factor contribution in future studies, particularly when using machine learning models in ecological research and dealing with numerous factors, before drawing relative conclusions. The balance between simple and accurate models is contested and we believe that our study will contribute to a better understand of the data behind this debate.
Abstract.
Li D, Li X, Du X, Zhang X, Wang J, Dungait JAJ, Quine TA, Green SM, Wen X, Yang Y, et al (2023). Response of heterotrophic respiration to vegetation restoration in a karst area of SW China. Land Degradation and Development, 34(9), 2523-2534.
Benaud P, Anderson K, James MR, Quine TA, Quinton JN, Brazier RE (2023). Structure-from-Motion Photogrammetry and Rare Earth Oxides can quantify diffuse and convergent soil loss and source apportionment. International Soil and Water Conservation Research
Wang Z, Zhang Y, Govers G, Tang G, Quine TA, Qiu J, Navas A, Fang H, Tan Q, Van Oost K, et al (2023). Temperature effect on erosion-induced disturbances to soil organic carbon cycling. Nature Climate Change
2022
Wu L, Liu H, Liang B, Zhu X, Cao J, Wang Q, Jiang L, Cressey EL, Quine TA (2022). A process-based model reveals the restoration gap of degraded grasslands in Inner Mongolian steppe.
Sci Total Environ,
806(Pt 3).
Abstract:
A process-based model reveals the restoration gap of degraded grasslands in Inner Mongolian steppe.
Due to the influence of climate change and extensive grazing, a large proportion of steppe grassland has been degraded worldwide. The Chinese government initiated a series of grassland restoration programs to reverse the degradation. However, the limiting factors and the restoration potential remain unknown. Here we present a process-based model to assess the restoration gap (RG) defined as maximum biomass differences between non-degraded and degraded grasslands with different degrees of soil and vegetation degradation. The process-based model Agricultural Production Systems Simulator (APSIM) was evaluated utilizing observation data from both typical and meadow steppes under natural conditions in terms of phenology, dynamics of above-ground biomass and soil water content. Scenario analysis and sensitivity analysis were subsequently performed to address the RG and controlling factors during 1969-2018. The results showed that the calibrated model performed well with r > 0.75 and model efficiency factor EF > 0.5 for all the simulation components. According to our model results, the RG was larger in typical steppe compared to that of meadow steppe and it increased with increasing soil and/or vegetation degradation, to ~60% under extremely degraded scenarios. Both soil and vegetation degradation led to reduced water use efficiency, with an elevated proportion of soil evaporation to evapotranspiration (Es/ET), however, the limiting factor for RG varied. The degradation of soil water holding capacity contributed more to RG regardless of climate conditions for typical steppe in all years and for meadow steppe in dry years. In wet years the importance of vegetation coverage reduction increased for RG in meadow steppe, where the relative importance of vegetation coverage (valued at 62.8%) was 25.6% higher than that of soil degradation. Our results demonstrated the importance of considering climate variations when developing protection and restoration programs for grassland ecosystems.
Abstract.
Author URL.
Yang Y, Zhang X, Hartley IP, Dungait JAJ, Wen X, Li D, Guo Z, Quine TA (2022). Contrasting rhizosphere soil nutrient economy of plants associated with arbuscular mycorrhizal and ectomycorrhizal fungi in karst forests (Apr, 10.1007/s11104-021-04950-9, 2021).
PLANT AND SOIL,
470(1-2), 95-96.
Author URL.
Quine TA, Cressey EL, Dungait JAJ, De Baets S, Meersmans J, Jones MW, Nicholas AP (2022). Geomorphically mediated carbon dynamics of floodplain soils and implications for net effect of carbon erosion.
Hydrological Processes,
36(9).
Abstract:
Geomorphically mediated carbon dynamics of floodplain soils and implications for net effect of carbon erosion
AbstractThe fate of organic carbon deposited in floodplain sediments is an important control on the magnitude and direction of the carbon flux from anthropogenically accelerated erosion and channelization of the riverine network. Globally, carbon deposition rates and mean residence time (MRT) within different geomorphic settings remains poorly constrained. We sampled soil profiles to 0.8 m depth from two geomorphic zones: active channel belt (ACB) and lowland floodplain, under long‐term pasture adjacent to the river Culm in SW England, UK. We evaluated sedimentation rates and carbon storage using fallout radionuclide 137Cs, particle size and total carbon analyses. Variation in decomposition was assessed via empirical (soil aggregate size, density fractionation combined with natural abundance 13C analysis) and modelling simulation (using the RothC model and catchment implications explored using a floodplain evolution model). Sedimentation and carbon accumulation rates were 5–6 times greater in the ACB than the floodplain. Carbon decomposition rates also varied with geomorphic setting. In floodplain cores, faster decomposition rates were indicated by greater 13C‐enrichment and subsoils dominated by mineral‐associated soil organic carbon. Whereas, in the ACB, carbon was less processed and 13C‐depleted, with light fraction and macroaggregate‐carbon throughout the cores, and RothC modelled decomposition rates were 4‐fold less than lowland floodplain cores. Including the ACB in floodplain carbon MRT calculations increased overall MRT by 10%. The major differences in the balance of sedimentation and decomposition rates between active and inactive floodplains suggests the relative extent of these contrasting zones is critical to the overall carbon balance. Restoration projects could enhance soil carbon storage by maximizing active floodplain areas by increasing river channel complexity.
Abstract.
Mariappan S, Hartley IP, Cressey EL, Dungait JAJ, Quine TA (2022). Soil burial reduces decomposition and offsets erosion-induced soil carbon losses in the Indian Himalaya.
Glob Chang Biol,
28(4), 1643-1658.
Abstract:
Soil burial reduces decomposition and offsets erosion-induced soil carbon losses in the Indian Himalaya.
The extent to which soil erosion is a net source or sink of carbon globally remains unresolved but has the potential to play a key role in determining the magnitude of CO2 emissions from land-use change in rapidly eroding landscapes. The effects of soil erosion on carbon storage in low-input agricultural systems, in acknowledged global soil erosion hotspots in developing countries, are especially poorly understood. Working in one such hotspot, the Indian Himalaya, we measured and modelled field-scale soil budgets, to quantify erosion-induced changes in soil carbon storage. In addition, we used long-term (1-year) incubations of separate and mixed soil horizons to better understand the mechanisms controlling erosion-induced changes in soil carbon cycling. We demonstrate that high rates of soil erosion did not promote a net carbon loss to the atmosphere at the field scale. Furthermore, our experiments showed that rates of decomposition in the organic matter-rich subsoil layers in depositional areas were lower per unit of soil carbon than from other landscape positions; however, these rates could be increased by mixing with topsoils. The results indicate that, the burial of soil carbon, and separation from fresh carbon inputs, led to reduced rates of decomposition offsetting potential carbon losses during soil erosion and transport within the cultivated fields. We conclude that the high rates of erosion experienced in these Himalayan soils do not, in isolation, drive substantial emissions of organic carbon, and there is the potential to promote carbon storage through sustainable agricultural practice.
Abstract.
Author URL.
Qiu S, Peng J, Quine TA, Green SM, Liu H, Liu Y, Hartley IP, Meersmans J (2022). Unraveling Trade‐Offs Among Reforestation, Urbanization, and Food Security in the South China Karst Region: How can a Hinterland Province Achieve SDGs?.
Earth's Future,
10(12).
Abstract:
Unraveling Trade‐Offs Among Reforestation, Urbanization, and Food Security in the South China Karst Region: How can a Hinterland Province Achieve SDGs?
AbstractWhether the world can achieve the United Nations Sustainable Development Goals (SDGs) largely depends on the ability of less‐developed areas to cope with multiple socio‐economic changes. The challenges that hinterland areas would face during the realization of SDGs has not yet received enough attentions. In this study, a context‐based assessment of regional food balances was conducted, considering key challenges related to socio‐economic development as well as land use competition under the framework of the shared socioeconomic pathways (SSPs) and the implementation of reforestation. We examined one of the poorest hinterland provinces in China as a case study, projecting its food deficit and exploring the potential threats to and opportunities for SDG realization by 2030, including population growth, urbanization, urban land expansion and reforestation. The projections revealed a crop deficit of 4.9–9.8 million tonnes, corresponding to the food demands of 10.2–20.6 million people. Approximately 76%–81% of this deficit was expected to be caused by increased food demand, rather than reforestation policies. Therefore, for this less‐developed area with low agricultural productivity and large groups of vulnerable people, population growth and urbanization are likely to result in demands for food that cannot be met locally. In addition, large‐scale reforestation projects, while enhancing a number of key ecosystem services, will increase the local food deficit by promoting the abandonment of cropland. This will result in greater reliance on food imports, with potential impacts on SDG realization in other regions. These findings highlight the need for integrated governance across multiple scales to ensure hinterland sustainability.
Abstract.
2021
Liang B, Liu H, Quine TA, Chen X, Hallett PD, Cressey EL, Zhu X, Cao J, Yang S, Wu L, et al (2021). Analysing and simulating spatial patterns of crop yield in Guizhou Province based on artificial neural networks.
Progress in Physical Geography,
45(1), 33-52.
Abstract:
Analysing and simulating spatial patterns of crop yield in Guizhou Province based on artificial neural networks
The area of karst terrain in China covers 3.63×106 km2, with more than 40% in the southwestern region over the Guizhou Plateau. Karst comprises exposed carbonate bedrock over approximately 1.30×106 km2 of this area, which suffers from soil degradation and poor crop yield. This paper aims to gain a better understanding of the environmental controls on crop yield in order to enable more sustainable use of natural resources for food production and development. More precisely, four kinds of artificial neural network were used to analyse and simulate the spatial patterns of crop yield for seven crop species grown in Guizhou Province, exploring the relationships with meteorological, soil, irrigation and fertilization factors. The results of spatial classification showed that most regions of high-level crop yield per area and total crop yield are located in the central-north area of Guizhou. Moreover, the three artificial neural networks used to simulate the spatial patterns of crop yield all demonstrated a good correlation coefficient between simulated and true yield. However, the Back Propagation network had the best performance based on both accuracy and runtime. Among the 13 influencing factors investigated, temperature (16.4%), radiation (15.3%), soil moisture (13.5%), fertilization of N (13.5%) and P (12.4%) had the largest contribution to crop yield spatial distribution. These results suggest that neural networks have potential application in identifying environmental controls on crop yield and in modelling spatial patterns of crop yield, which could enable local stakeholders to realize sustainable development and crop production goals.
Abstract.
Li D, Zhang X, Dungait JAJ, Wen X, Quine TA, Wang Q (2021). Changes in the biological N<inf>2</inf>-fixation rates and diazotrophic community as vegetation recovers on abandoned farmland in a karst region of China.
Applied Soil Ecology,
158Abstract:
Changes in the biological N2-fixation rates and diazotrophic community as vegetation recovers on abandoned farmland in a karst region of China
The successful regeneration of karst landscapes that have been severely degraded by intensive agriculture relies on the recovery of biological nitrogen fixation (BNF) by diazotrophic communities in soils after nitrogen (N) derived from synthetic fertilizers dissipates through the soil. It is important to understand the mechanisms that drive BNF because there must be enough bioavailable N in soils to support the recovery of native vegetation communities that are best adapted to erosion-prone karst landscapes. In this study, we quantified the response of the diazotrophic population in topsoil (0–10 cm deep) along a vegetation restoration gradient (sloping cropland > abandoned sloping cropland > secondary forest > primary forest) in the Puding Karst Critical Zone Observatory, Guizhou Province, southwest China from the absolute and specific BNF rates, determined using the acetylene reduction method and qPCR and MiSeq sequencing of nifH genes. The nifH phylogenetic diversities increased as the vegetation increased in maturity and were positively correlated with soil moisture and the N to phosphorus ratio (p < 0.05). The diazotrophic community structure changed with the vegetation recovery time (p < 0.05). Rhizobiales accounted for between 38% and 45% of the total nifH gene sequences and were the most abundant order in the vegetation that had been recovering for the longest time. We found that the soil bulk density was a strong control on the diazotroph community structure and was negatively correlated with Rhizobiales. The absolute and specific BNF rates were the highest in primary forest and abandoned sloping cropland, respectively (p < 0.05). The results from stepwise multiple regression showed that 50% of the variation in the absolute BNF rates was explained by SWC, and 55% of the variation in the nifH specific rates was explained by the available N contents and the diazotrophic community structure. We suggest that the recovery of degraded karst could be accelerated by managing the soil physical structure so that the environment is suitable for diazotrophic communities, which would then improve the BNF efficiency.
Abstract.
Hao Z, Gao Y, Green SM, Wen X, Yang J, Xiong B, Quine TA, He N (2021). Chemical Characteristics of Flow Driven by Rainfall and Associated Impacts on Shallow Groundwater Quality in a Karst Watershed, Southwest China.
Environmental Processes,
8(2), 615-636.
Abstract:
Chemical Characteristics of Flow Driven by Rainfall and Associated Impacts on Shallow Groundwater Quality in a Karst Watershed, Southwest China
Monitoring from 2016 to 2018 was used to investigate seasonal variation of chemical characteristics and define the water quality status within a subsurface river system in a karst region of Southwest China. For this, the water quality index (WQI) and principal component analysis (PCA) were employed. Results showed that baseflow and constituents, i.e. TN, TP, NO2−-N, and SO42− exhibited seasonal variation. Arsenic and selenium were the main pollutants found in the river system of the Houzhai river basin. Total dissolved solids (TDS), pH, selenium, TP, NO2−-N, and TN were obviously impacted by precipitation during the precipitation-derived flow processes. The groundwater quality was categorized as “very poor” throughout the entire monitoring period, with WQI values ranging from 62 to 70. In particular, TN, TP, selenium, and arsenic scores ranged from 80 to 100, which are considered unsuitable for potable water use. In order to ensure the safety of groundwater as a potable water source, administrators must recognize the importance of preventing the cross-contamination of surface water and groundwater to guarantee the safety of water and the health of local residents in karst areas.
Abstract.
Lu H, Li S, Ma M, Bastrikov V, Chen X, Ciais P, Dai Y, Ito A, Ju W, Lienert S, et al (2021). Comparing machine learning-derived global estimates of soil respiration and its components with those from terrestrial ecosystem models.
Environmental Research Letters,
16(5).
Abstract:
Comparing machine learning-derived global estimates of soil respiration and its components with those from terrestrial ecosystem models
The CO2 efflux from soil (soil respiration (SR)) is one of the largest fluxes in the global carbon (C) cycle and its response to climate change could strongly influence future atmospheric CO2 concentrations. Still, a large divergence of global SR estimates and its autotrophic (AR) and heterotrophic (HR) components exists among process based terrestrial ecosystem models. Therefore, alternatively derived global benchmark values are warranted for constraining the various ecosystem model output. In this study, we developed models based on the global soil respiration database (version 5.0), using the random forest (RF) method to generate the global benchmark distribution of total SR and its components. Benchmark values were then compared with the output of ten different global terrestrial ecosystem models. Our observationally derived global mean annual benchmark rates were 85.5 ± 40.4 (SD) Pg C yr-1 for SR, 50.3 ± 25.0 (SD) Pg C yr-1 for HR and 35.2 Pg C yr-1 for AR during 1982-2012, respectively. Evaluating against the observations, the RF models showed better performance in both of SR and HR simulations than all investigated terrestrial ecosystem models. Large divergences in simulating SR and its components were observed among the terrestrial ecosystem models. The estimated global SR and HR by the ecosystem models ranged from 61.4 to 91.7 Pg C yr-1 and 39.8 to 61.7 Pg C yr-1, respectively. The most discrepancy lays in the estimation of AR, the difference (12.0-42.3 Pg C yr-1) of estimates among the ecosystem models was up to 3.5 times. The contribution of AR to SR highly varied among the ecosystem models ranging from 18% to 48%, which differed with the estimate by RF (41%). This study generated global SR and its components (HR and AR) fluxes, which are useful benchmarks to constrain the performance of terrestrial ecosystem models.
Abstract.
Yang Y, Zhang X, Hartley IP, Dungait JAJ, Wen X, Li D, Guo Z, Quine TA (2021). Contrasting rhizosphere soil nutrient economy of plants associated with arbuscular mycorrhizal and ectomycorrhizal fungi in karst forests. Plant and Soil, 470(1-2), 81-93.
Guo Z, Zhang X, Dungait JAJ, Green SM, Wen X, Quine TA (2021). Contribution of soil microbial necromass to SOC stocks during vegetation recovery in a subtropical karst ecosystem.
Sci Total Environ,
761Abstract:
Contribution of soil microbial necromass to SOC stocks during vegetation recovery in a subtropical karst ecosystem.
Carbon sequestration is a key soil function, and an increase in soil organic carbon (SOC) is an indicator of ecosystem recovery because it underpins other ecosystem services by acting as a substrate for the soil microbial community. The soil microbial community constitutes the active pool of SOC, and its necromass (microbial residue carbon, MRC) contributes strongly to the stable SOC pool. Therefore, we propose that the potential for restoration of degraded karst ecosystems lies in the abundance of soil microbial community and the persistence of its necromass, and may be measured by changes in its contribution to the active and stable SOC pools during recovery. We investigated changes in SOC stocks using an established space-for-time chronosequence along a perturbation gradient in the subtropical karst ecosystem: sloping cropland
Abstract.
Author URL.
Shi L, Liu H, Xu C, Liang B, Cao J, Cressey EL, Quine TA, Zhou M, Zhao P (2021). Decoupled heatwave-tree growth in large forest patches of Larix sibirica in northern Mongolian Plateau. Agricultural and Forest Meteorology, 311, 108667-108667.
Cao J, Liu H, Zhao B, Li Z, Liang B, Shi L, Wu L, Cressey EL, Quine TA (2021). High forest stand density exacerbates growth decline of conifers driven by warming but not broad-leaved trees in temperate mixed forest in northeast Asia.
Science of the Total Environment,
795Abstract:
High forest stand density exacerbates growth decline of conifers driven by warming but not broad-leaved trees in temperate mixed forest in northeast Asia
Increasing temperature over recent decades is expected to positively impact tree growth in humid regions. However, high stand density could increase the negative effects of warming-induced drought through inter-tree competition. How neighborhood competition impacts tree growth responding to climate change remains unclear. Here, we utilized the Changbai Mountain region in northeastern Asia as our study area. We quantified individual tree growth using tree-ring samples collected from three dominant tree species growing in three forest stand density levels. We estimated the effects of climate warming and forest stand density on growth processes and tested for a species-specific response to climate. Our results demonstrated that overall 25% of Korean pine, but only ~3% of Mongolian oak and ~ 4% of Manchurian ash experienced growth reduction. Increased forest density can also exacerbate growth reduction. We identified a climate turning point in 1984, where warming rapidly increased, and defined two groups, “enhance group” (EG) and “decline group” (DG), according to the individual tree growth trend after 1984. For the EG, climate warming increased temperature sensitivity, but the temperature sensitivity declined with increasing stand density for the whole study period. For the DG, tree growth sensitivity shifted from temperature to precipitation after 1984, driven by increased competition pressure under climate warming. Our study concludes that growth decline from warming-induced drought might be amplified by high forest stand density, was especially pronounced in conifer trees.
Abstract.
Liang B, Quine TA, Liu H, Cressey EL, Bateman I (2021). How can We Realize Sustainable Development Goals in Rocky Desertified Regions by Enhancing Crop Yield with Reduction of Environmental Risks?.
REMOTE SENSING,
13(9).
Author URL.
Peng J, Jiang H, Liu Q, Green SM, Quine TA, Liu H, Qiu S, Liu Y, Meersmans J (2021). Human activity vs. climate change: Distinguishing dominant drivers on LAI dynamics in karst region of southwest China.
Sci Total Environ,
769Abstract:
Human activity vs. climate change: Distinguishing dominant drivers on LAI dynamics in karst region of southwest China.
Understanding the impacts of climate change and human activities on vegetation is of great significance to the sustainable development of terrestrial ecosystems. However, most studies focused on the overall impact over a period and rarely examined the time-lag effect of vegetation's response to climatic factors when exploring the driving mechanisms of vegetation dynamics. In this study, we identified key areas driven by either positive or negative human activities and climate change. Taking the three karst provinces of southwest China as the case study area, a Leaf Area Index (LAI)-climate model was constructed by quantifying the time-lag effect. Then the associated residual threshold was calculated to identify the vegetation change areas dominated by human activities and climate change. The results showed that, during the implementation period of ecological restoration projects from 1999 to 2015, positive impact areas of human activities were mainly distributed among the implementation areas of ecological restoration projects, accounting for 5.61% of the total area. For another, the negative impact areas were mainly distributed across the mountainous area of Yunnan Province, accounting for 1.30% of the total area. Karst landform had the greatest influence on the areas dominated by positive human activities, whereas both topography and karst landform significantly affected the areas dominated by negative human activities. Urban development level had the greatest impact on the areas dominated by climate change. The outcomes of this study provided scientific supports for the sustainable development of ecological restoration projects in China's karst region.
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Author URL.
Li D, Zhang X, Dungait JAJ, Green SM, Wen X, Quine TA, Wang Q (2021). Main controls on the denitrification rates during cropland revegetation in the southwest China Karst Critical Zone Observatory.
Agriculture, Ecosystems and Environment,
308Abstract:
Main controls on the denitrification rates during cropland revegetation in the southwest China Karst Critical Zone Observatory
The revegetation of karst ecosystems in subtropical southwest China that became severely degraded because of intensive agriculture relies on the persistence and recovery of soil functions such as nutrient cycling. Denitrification is a nitrogen (N) removal process that is carried out by nitrifying and denitrifying microorganisms. We still do not have a comprehensive understanding of denitrification and what drives it during revegetation of cropland in degraded karst ecosystems. We used the space-for-time chronosequence method to establish a restoration gradient (sloping cropland, abandoned sloping cropland, and secondary and primary forest) within the Karst Critical Zone Observatory in southwest China. We quantified the abundances of the nitrifier and denitrifier microbial communities and measured the potential denitrification rates (PDR) and basal denitrification rates (BDR) in incubated soils to investigate the denitrification activity in soils at different stages of restoration. The PDR increased through the cropland revegetation phases, and the BDR was lowest in the abandoned sloping cropland (p < 0.05). Both the PDR and BDR were positively correlated with the denitrifier abundances (i.e. nitrite reductase, nirK, and nirS), but were negatively correlated with nitrifier abundances (i.e. ammonia oxidation, AOA, and AOB). The BDR/PDR ratio was 84 % in the sloping cropland but was only 1% in the primary forest, which suggests that the N cycling was inefficient (‘leaky’) in actively managed farmland soils but was ‘tight’ in forest soils. The AOB and nirS abundances explained most of the PDR in the sloping cropland and abandoned sloping cropland, while the soil phosphorus (P) contents explained most of the variation in BDR and PDR in land that was forested in later phases of revegetation. Progressive increases in the PDR as the revegetation progressed was directly controlled by the soil available P and total P contents. Available P was also associated with increases in the carbon (C) and N contents, which influenced the BDR indirectly through increased abundances of nirK and nirS. We conclude that revegetation of cropland helped to facilitate ‘tight’ N-cycling in poor karst soils, and we suggest that judicious P fertilization on sloping cropland would reduce the denitrification activity in degraded ecosystems.
Abstract.
Luo Y, Wang H, Meersmans J, Green SM, Quine TA, Feng S (2021). Modeling soil erosion between 1985 and 2014 in three watersheds on the carbonate-rock dominated Guizhou Plateau, SW China, using WaTEM/SEDEM.
Progress in Physical Geography,
45(1), 53-81.
Abstract:
Modeling soil erosion between 1985 and 2014 in three watersheds on the carbonate-rock dominated Guizhou Plateau, SW China, using WaTEM/SEDEM
The Guizhou Plateau, SW China is largely underlain by carbonate rocks. Because soils are thin, soil loss remains a serious problem despite low erosion rates. Further understanding the impacts of changes in rainfall, land use and differences in topography on sediment yield and delivery may assist in the development of suitable policies to reduce soil erosion on the plateau. A spatially distributed soil erosion and sediment delivery model (WaTEM/SEDEM) was applied to investigate temporal–spatial changes in soil erosion between 1985 and 2014 in three watersheds (Dadukou (DDK), Caopingtou (CPT) and Gaoche (GC)) located in the southwest Guizhou Plateau. The WaTEM/SEDEM model was calibrated and validated using data on sediment yields measured at the watershed scale. The total sediment yield (SY) and soil erosion modulus (SEM) firstly decreased followed by an increase, whereas the sediment delivery ratio (SDR) remained almost unchanged over the 30-year period. The major sediment source was dry farmlands. SY was the highest in the largest DDK watershed. The highest SEM occurred in the CPT watershed due to steep terrain and high ratio of dry farmland areas on steeper slopes. SEM was the lowest in the GC watershed where slope gradient and ratio of dry farmland on steeper slopes are low. SDR was the highest in the GC watershed because of its topographic characteristics. SEM was sensitive to precipitation fluctuations in the GC, DDK and particularly in the steep and intensively eroded CPT watershed, while changes in dry farmland ratio influenced the SEM in the CPT and DDK watersheds but not in the gentle and mildly eroded GC watershed. Changes in forest ratio had significant impacts on SEM only in the GC watershed. Since responses of soil erosion to variations or differences in the main impact factors differ in the different watersheds, soil conservation strategies should be watershed specific.
Abstract.
Liu S, Zhang X, Dungait JAJ, Quine TA, Razavi BS (2021). Rare microbial taxa rather than phoD gene abundance determine hotspots of alkaline phosphomonoesterase activity in the karst rhizosphere soil.
Biology and Fertility of Soils,
57(2), 257-268.
Abstract:
Rare microbial taxa rather than phoD gene abundance determine hotspots of alkaline phosphomonoesterase activity in the karst rhizosphere soil
The spatial distribution of alkaline phosphomonoesterase (ALP) activity in the rhizosphere and bulk soil of three plants (Zea mays, Medicago sativa, and Cyperus rotundus) grown in a karst soil (pH 8.27) was visualized using in situ soil zymography. According to the zymogram images, we identified and precisely collected soil samples from hotspots and non-hotspots of ALP activity, and then analyzed the phoD genes that encoded alkaline phosphomonoesterase and assessed the microbial community. The results showed that (1) the phoD abundance in the plant types varied and was highest in the alfalfa and lowest in the maize; (2) Proteobacteria dominated the phoD-harboring microbes in the rhizosphere and Actinobacteria dominated the phoD-harboring microbes in the bulk soil, and (3) the ALP activity was positively correlated with the relative abundance of the diazotrophic Azotobacter, but negatively correlated with the phoD gene abundance, microbial community richness, and diversity. By coupling zymography and microbial molecular approaches, we identified hotspots of enzymatic and microbial activity in rhizosphere soil and evaluated the relative contributions from potential active microorganisms. We found that the function of specific phoD-harboring microorganisms in these hotspots differed depending on the plant in the soil, which had implications for phosphorus (P) management in P-limited karst soils. The results also suggested that free-living N2-fixing bacteria (Azotobacter) might promote ALP activity, thereby emphasizing vital linkages between, and coupling of, the soil nutrient cycles.
Abstract.
Benaud P, Anderson K, Evans M, Farrow L, Glendell M, James MR, Quine TA, Quinton JN, Rickson RJ, Brazier RE, et al (2021). Reproducibility, open science and progression in soil erosion research. A reply to “Response to ‘National-scale geodata describe widespread accelerated soil erosion’ Benaud et al. (2020) Geoderma 271, 114378” by Evans and Boardman (2021). Geoderma, 402
Xia S, Wang W, Song Z, Kuzyakov Y, Guo L, Van Zwieten L, Li Q, Hartley IP, Yang Y, Wang Y, et al (2021). Spartina alterniflora invasion controls organic carbon stocks in coastal marsh and mangrove soils across tropics and subtropics.
Glob Chang Biol,
27(8), 1627-1644.
Abstract:
Spartina alterniflora invasion controls organic carbon stocks in coastal marsh and mangrove soils across tropics and subtropics.
Coastal wetlands are among the most productive ecosystems and store large amounts of organic carbon (C)-the so termed "blue carbon." However, wetlands in the tropics and subtropics have been invaded by smooth cordgrass (Spartina alterniflora) affecting storage of blue C. To understand how S. alterniflora affects soil organic carbon (SOC) stocks, sources, stability, and their spatial distribution, we sampled soils along a 2500 km coastal transect encompassing tropical to subtropical climate zones. This included 216 samplings within three coastal wetland types: a marsh (Phragmites australis) and two mangroves (Kandelia candel and Avicennia marina). Using δ13 C, C:nitrogen (N) ratios, and lignin biomarker composition, we traced changes in the sources, stability, and storage of SOC in response to S. alterniflora invasion. The contribution of S. alterniflora-derived C up to 40 cm accounts for 5.6%, 23%, and 12% in the P. australis, K. candel, and A. marina communities, respectively, with a corresponding change in SOC storage of +3.5, -14, and -3.9 t C ha-1. SOC storage did not follow the trend in aboveground biomass from the native to invasive species, or with vegetation types and invasion duration (7-15 years). SOC storage decreased with increasing mean annual precipitation (1000-1900 mm) and temperature (15.3-23.4℃). Edaphic variables in P. australis marshes remained stable after S. alterniflora invasion, and hence, their effects on SOC content were absent. In mangrove wetlands, however, electrical conductivity, total N and phosphorus, pH, and active silicon were the main factors controlling SOC stocks. Mangrove wetlands were most strongly impacted by S. alterniflora invasion and efforts are needed to focus on restoring native vegetation. By understanding the mechanisms and consequences of invasion by S. alterniflora, changes in blue C sequestration can be predicted to optimize storage can be developed.
Abstract.
Author URL.
Wang L, Liu H, Leavitt S, Cressey EL, Quine TA, Shi J, Shi S (2021). Tree-ring δ18O identifies similarity in timing but differences in depth of soil water uptake by trees in mesic and arid climates. Agricultural and Forest Meteorology, 308-309, 108569-108569.
Qiu S, Peng J, Dong J, Wang X, Ding Z, Zhang H, Mao Q, Liu H, Quine TA, Meersmans J, et al (2021). Understanding the relationships between ecosystem services and associated social-ecological drivers in a karst region: a case study of Guizhou Province, China.
Progress in Physical Geography,
45(1), 98-114.
Abstract:
Understanding the relationships between ecosystem services and associated social-ecological drivers in a karst region: a case study of Guizhou Province, China
Understanding the relationships among multiple ecosystem services could improve the landscape capacity to provide benefits to human society. However, the underlying mechanisms shaping ecosystem services relationships are still unclear although some studies have been conducted to explore how natural and socioeconomic factors influence the relationships among ecosystem services. In this study, the karst landscape in southwestern China, a vulnerable system with intensive human activities, was focused on, aiming to explore relationships between ecosystem services and associated social and ecological factors. The results showed that the distribution of eight individual ecosystem services were spatially heterogeneous and clustered based on the characteristics of the karst landscape. The relationships between provisioning services and regulating services, such as grain production and net primary productivity, as well as water yield and soil retention, were quite different between high karst coverage regions and low karst coverage regions. Among five ecosystem service bundles identified, ecosystem services in the urban development bundle were mainly determined by socioeconomic factors, while in the other four bundles of multifunction, grain production, habitat conservation, and carbon sequestration, ecosystem services were dominated by ecological factors. However, socioeconomic factors (i.e. population density and night-time light intensity) appeared to explain the overall ecosystem service delivery more than karst terrain. This study provided insights for sustainable ecosystem management in a vulnerable karst region through exploring social-ecological factors of the relationships among ecosystem services.
Abstract.
2020
Jiang Z, Liu H, Wang H, Peng J, Meersmans J, Green SM, Quine TA, Wu X, Song Z (2020). Bedrock geochemistry influences vegetation growth by regulating the regolith water holding capacity.
Nature Communications,
11(1).
Abstract:
Bedrock geochemistry influences vegetation growth by regulating the regolith water holding capacity
AbstractAlthough low vegetation productivity has been observed in karst regions, whether and how bedrock geochemistry contributes to the low karstic vegetation productivity remain unclear. In this study, we address this knowledge gap by exploring the importance of bedrock geochemistry on vegetation productivity based on a critical zone investigation across a typical karst region in Southwest China. We show silicon and calcium concentrations in bedrock are strongly correlated with the regolith water loss rate (RWLR), while RWLR can predict vegetation productivity more effectively than previous models. Furthermore, the analysis based on 12 selected karst regions worldwide further suggest that lithological regulation has the potential to obscure and distort the influence of climate change. Our study implies that bedrock geochemistry could exert effects on vegetation growth in karst regions and highlights that the critical role of bedrock geochemistry for the karst region should not be ignored in the earth system model.
Abstract.
Peng J, Tian L, Zhang Z, Zhao Y, Green SM, Quine TA, Liu H, Meersmans J (2020). Distinguishing the impacts of land use and climate change on ecosystem services in a karst landscape in China.
Ecosystem Services,
46Abstract:
Distinguishing the impacts of land use and climate change on ecosystem services in a karst landscape in China
Land use and climate change are the most important factors driving the change of ecosystem services (ESs). It is critical to understand the mechanisms behind such changes for improving ESs. However, existing studies mainly focuse on ES changes due to combined effects of land use and climate change, while the interactions between these factors and ESs remain unclear. This study took Guizhou Province, China as the case study area and examined the impact of land use and climate change on three ESs, i.e. net primary productivity (NPP), soil retention, and water yield. The impacts of land use and climate change on ESs were compared within and between different zones (including terrain zones, geomorphic zones, and urban development zones). The results showed that all the three ESs were characterized with high values in the south and low values in the north, and an overall increasing trend during 2000–2015. Changes in NPP and water yield were dominated by land use change, accounting for 85.2% and 74.9% of the total area, respectively, whereas for soil retention it was climate change, accounting for 71.0% of area proportion. As to zoning contrast, the impact of climate change on NPP and water yield differed the most across geomorphic zones, with terrain zones for soil retention. The impact of land use change on all the three ESs behaved the most difference across urban development zones, indicating high sensitivity of ESs to human activity.
Abstract.
Dai J, Liu H, Wang Y, Guo Q, Hu T, Quine T, Green S, Hartmann H, Xu C, Liu X, et al (2020). Drought-modulated allometric patterns of trees in semi-arid forests.
Communications Biology,
3(1).
Abstract:
Drought-modulated allometric patterns of trees in semi-arid forests
AbstractTree allometry in semi-arid forests is characterized by short height but large canopy. This pattern may be important for maintaining water-use efficiency and carbon sequestration simultaneously, but still lacks quantification. Here we use terrestrial laser scanning to quantify allometry variations of Quercus mongolica in semi-arid forests. With tree height (Height) declining, canopy area (CA) decreases with substantial variations. The theoretical CA-Height relationship in dynamic global vegetation models (DGVMs) matches only the 5th percentile of our results because of CA underestimation and Height overestimation by breast height diameter (DBH). Water supply determines Height variation (P = 0.000) but not CA (P = 0.2 in partial correlation). The decoupled functions of stem, hydraulic conductance and leaf spatial arrangement, may explain the inconsistency, which may further ensure hydraulic safety and carbon assimilation, avoiding forest dieback. Works on tree allometry pattern and determinant will effectively supply tree drought tolerance studying and support DGVM improvements.
Abstract.
Jones MW, Coppola AI, Santín C, Dittmar T, Jaffé R, Doerr SH, Quine TA (2020). Fires prime terrestrial organic carbon for riverine export to the global oceans.
Nature Communications,
11(1).
Abstract:
Fires prime terrestrial organic carbon for riverine export to the global oceans
AbstractBlack carbon (BC) is a recalcitrant form of organic carbon (OC) produced by landscape fires. BC is an important component of the global carbon cycle because, compared to unburned biogenic OC, it is selectively conserved in terrestrial and oceanic pools. Here we show that the dissolved BC (DBC) content of dissolved OC (DOC) is twice greater in major (sub)tropical and high-latitude rivers than in major temperate rivers, with further significant differences between biomes. We estimate that rivers export 18 ± 4 Tg DBC year−1 globally and that, including particulate BC fluxes, total riverine export amounts to 43 ± 15 Tg BC year−1 (12 ± 5% of the OC flux). While rivers export ~1% of the OC sequestered by terrestrial vegetation, our estimates suggest that 34 ± 26% of the BC produced by landscape fires has an oceanic fate. Biogeochemical models require modification to account for the unique dynamics of BC and to predict the response of recalcitrant OC export to changing environmental conditions.
Abstract.
Hao Q, Yang S, Song Z, Ran X, Yu C, Chen C, Van Zwieten L, Quine TA, Liu H, Wang Z, et al (2020). Holocene carbon accumulation in lakes of the current east Asian monsoonal margin: Implications under a changing climate.
Sci Total Environ,
737Abstract:
Holocene carbon accumulation in lakes of the current east Asian monsoonal margin: Implications under a changing climate.
Carbon (C) present in lake sediments is an important global sink for CO2; however, an in-depth understanding of the impact of climate variability and the associated changes in vegetation on sediment C dynamics is still lacking. A total of 13 lakes were studied to quantify the influence of climate and vegetation on the reconstructed Holocene C accumulation rate (CAR) in lake sediments of the modern East Asian monsoonal margin. The corresponding paleoclimate information was assessed, including the temperature (30-90°N in the Northern Hemisphere) and precipitation (indicated by the δ18O of the Sanbao, Dongge, and Hulu caves). The Holocene vegetation conditions were inferred by pollen records, including arboreal pollen/non-arboreal pollen and pollen percentages. The results showed that the peak CAR occurred during the mid-Holocene, coinciding with the strongest period of the East Asian summer monsoon and expansion of forests. Lakes in the temperate steppe (TS) regions had a mean CAR of 13.41 ± 0.88 g C m-2 yr-1, which was significantly greater than the CARs of temperate desert (TD) and highland meadow/steppe (HMS; 6.76 ± 0.29 and 7.39 ± 0.73 g C m-2 yr-1, respectively). The major influencing factor for the TS sub-region was vegetation dynamics, especially the proportion of arboreal vegetation, while temperature and vegetation coverage were more important for the HMS. These findings indicate that C accumulation in lake sediments is linked with climate and vegetation changes over long timescales; however, there was notable spatial heterogeneity in the CARs, such as opposing temporal changes and different major influencing factors among the three sub-regions during the mid-Holocene. Aridification and forest loss would decrease C storage. However, prediction of C accumulation remains difficult because of the spatial heterogeneity in CARs and the interaction between the CAR and various factors under future climate change conditions.
Abstract.
Author URL.
Quine TA, Van Oost K (2020). Insights into the future of soil erosion. Proceedings of the National Academy of Sciences, 117(38), 23205-23207.
De Baets S, Denbigh TDG, Smyth KM, Eldridge BM, Weldon L, Higgins B, Matyjaszkiewicz A, Meersmans J, Larson ER, Chenchiah IV, et al (2020). Micro-scale interactions between Arabidopsis root hairs and soil particles influence soil erosion.
Communications Biology,
3(1).
Abstract:
Micro-scale interactions between Arabidopsis root hairs and soil particles influence soil erosion
AbstractSoil is essential for sustaining life on land. Plant roots play a crucial role in stabilising soil and minimising erosion, although these mechanisms are still not completely understood. Consequently, identifying and breeding for plant traits to enhance erosion resistance is challenging. Root hair mutants in Arabidopsis thaliana were studied using three different quantitative methods to isolate their effect on root-soil cohesion. We present compelling evidence that micro-scale interactions of root hairs with surrounding soil increase soil cohesion and reduce erosion. Arabidopsis seedlings with root hairs were more difficult to detach from soil, compost and sterile gel media than those with hairless roots, and it was 10-times harder to erode soil from roots with than without hairs. We also developed a model that can consistently predict the impact root hairs make to soil erosion resistance. Our study thus provides new insight into the mechanisms by which roots maintain soil stability.
Abstract.
Benaud P, Anderson K, Evans M, Farrow L, Glendell M, James MR, Quine TA, Quinton JN, Rawlins B, Jane Rickson R, et al (2020). National-scale geodata describe widespread accelerated soil erosion.
Geoderma,
371Abstract:
National-scale geodata describe widespread accelerated soil erosion
Accelerated soil erosion can result in substantial declines in soil fertility and has devastating environmental impacts. Consequently, understanding if rates of soil erosion are acceptable is of local and global importance. Herein we use empirical soil erosion observations collated into an open access geodatabase to identify the extent to which existing data and methodological approaches can be used to develop an empirically-derived understanding of soil erosion in the UK (by way of an example). The findings indicate that whilst mean erosion rates in the UK are low, relative to the rest of Europe for example, 16% of observations on arable land were greater than the supposedly tolerable rate of 1 t ha−1 yr−1 and maximum erosion rates were as high as 91.7 t ha−1 yr−1. However, the analysis highlights a skew in existing studies towards locations with a known erosion likelihood and methods that are biased towards single erosion pathways, rather than an all-inclusive study of erosion rates and processes. Accordingly, we suggest that future soil erosion research and policy must address these issues if an accurate assessment of soil erosion rates at the national-scale are to be established. The interactive geodatabase published alongside this paper offers a platform for the simultaneous development of soil erosion research, formulation of effective policy and better protection of soil resources.
Abstract.
Liang B, Liu H, Chen X, Zhu X, Cressey EL, Quine TA (2020). Periodic relations between terrestrial vegetation and climate factors across the globe.
Remote Sensing,
12(11).
Abstract:
Periodic relations between terrestrial vegetation and climate factors across the globe
In this paper, cross-spectrum analysis was used to verify the agreement of periodicity between the global LAI (leaf area index) and climate factors. The results demonstrated that the LAI of deciduous forests and permanent wetlands have high agreement with temperature, rainfall and radiation over annual cycles. A low agreement between the LAI and seasonal climate variables was observed for some of the temperate and tropical vegetation types including shrublands and evergreen broadleaf forests, possibly due to the diversity of vegetation and human activities. Across all vegetation types, the LAI demonstrated a large time lag following variation in radiation (>1 month), whereas relatively short lag periods were observed between the LAI and annual temperature (around 2 weeks)/rainfall patterns (less than 10 days), suggesting that the impact of radiation on global vegetation growth is relatively slow, which is in accord with the results of previous studies. This work can provide a benchmark of the phenological drivers in global vegetation, from the perspective of periodicity, as well as helping to parameterize and refine the DGVMs (Dynamic Global Vegetation Models) for different vegetation types.
Abstract.
Wang Y, Dungait JAJ, Xing K, Green SM, Hartley I, Tu C, Quine TA, Tian J, Kuzyakov Y (2020). Persistence of soil microbial function at the rock-soil interface in degraded karst topsoils.
LAND DEGRADATION & DEVELOPMENT,
31(2), 251-265.
Author URL.
Xue Y, Tian J, Quine TA, Powlson D, Xing K, Yang L, Kuzyakov Y, Dungait JAJ (2020). The persistence of bacterial diversity and ecosystem multifunctionality along a disturbance intensity gradient in karst soil.
Science of the Total Environment,
748Abstract:
The persistence of bacterial diversity and ecosystem multifunctionality along a disturbance intensity gradient in karst soil
Extensive, progressive rock emergence causes localized variations in soil biogeochemical and microbial properties that may influence the capacity for the regeneration of degraded karst ecosystems. It is likely that karst ecosystem recovery relies on the persistence of soil functions at the microbial scale, and we aimed to explored the role of interactions between soil bacterial taxa and identify keystone species that deliver key biogeochemical functions, i.e. carbon (C) and nutrient (nitrogen, N and phosphorus, P) cycling. We applied high-throughput sequencing and phylogenetic molecular ecological network approaches to topsoils sampled at rock-soil interfaces and adjacent bulk soil along an established gradient of land-use intensity in the Chinese Karst Critical Zone Observatory. Bacterial α-diversity was greater under increased perturbation and at the rock-soil interface compared to bulk soils under intensive cultivation. However, bacterial ecological networks were less intricate and connected fewer keystone taxa as human disturbance increased and at the rock-soil interface. Co-occurrence within the bacterial community in natural primary forest soils was 13% larger than cultivated soils. The relative abundances of keystone taxa Acidobacteria, Bacteroidetes and Chloroflexi increased with land-use intensity, while Proteobacteria, Actinobacteria and Verrucomicrobia decreased by up to 6%. In general, Bacteroidetes, Verrucomicrobia and Chlorobi were related to C-cycling, Proteobacteria, Actinobacteria and Chloroflexi were related to N-cycling, and Actinobacteria and Nitrospirae were related to both N- and P-cycling. Proteobacteria and Chlorobi affected C-cycling and multiple functionality indexes in the abandoned land. We conclude that increasing land-use intensity changed the soil bacterial community structure and decreased bacterial interactions. However, increases in α-diversity at the rock-soil interface in cultivated soils indicated that major soil functions related to biogeochemical cycling were maintained within keystone taxa in this microenvironment. Our study provides foundations to test the success of different regeneration practices in restoring soil microbial diversity and the multifunctionality of karst ecosystems.
Abstract.
2019
Evans DL, Quinton JN, Tye AM, Rodés Á, Davies JAC, Mudd SM, Quine TA (2019). Arable soil formation and erosion: a hillslope-based cosmogenic nuclide study in the United Kingdom.
SOIL,
5(2), 253-263.
Abstract:
Arable soil formation and erosion: a hillslope-based cosmogenic nuclide study in the United Kingdom
Arable soils are critical resources that support multiple ecosystem services. They are frequently threatened, however, by accelerated erosion. Subsequently, policy to ensure their long-term security is an urgent societal priority. Although their long-term security relies upon a balance between the rates of soil loss and formation, there have been few investigations of the formation rates of soils supporting arable agriculture. This paper addresses this knowledge gap by presenting the first isotopically constrained soil formation rates for an arable (Nottinghamshire, UK) and coniferous woodland hillslope (Shropshire, UK). Rates ranged from 0.026 to 0.096 mm yr-1 across the two sites. These rates fall within the range of previously published rates for soils in temperate climates and on sandstone lithologies but significantly differed from those measured in the only other UK-based study. We suggest this is due to the parent material at our sites being more susceptible to weathering. Furthermore, soil formation rates were found to be greatest for aeolian-derived sandstone when compared with fluvially derived lithology raising questions about the extent to which the petrographic composition of the parent material governs rates of soil formation. On the hillslope currently supporting arable agriculture, we utilized cosmogenically derived rates of soil formation and erosion in a first-order lifespan model and found, in a worst-case scenario, that the backslope a horizon could be eroded in 138 years with bedrock exposure occurring in 212 years under the current management regime. These findings represent the first quantitative estimate of cultivated soil lifespans in the UK.
Abstract.
Jones M, Aragão LEOC, Dittmar T, Rezende CE, Almeida MG, Johnson BT, Marques JSJ, Niggemann J, Rangel TP, Quine TA, et al (2019). Environmental Controls on the Riverine Export of Dissolved Black Carbon: Supplementary Dataset.
Abstract:
Environmental Controls on the Riverine Export of Dissolved Black Carbon: Supplementary Dataset
Each year, tropical rivers export a dissolved organic carbon (DOC) flux to the global oceans that is equivalent to ~4% of the global land sink for atmospheric CO¬2. Among the most refractory fractions of terrigenous DOC is dissolved black carbon (DBC), which constitutes ~10% of the total flux and derives from the charcoal and soot (aerosol) produced during biomass burning and fossil fuel combustion. Black carbon (BC) has disproportionate storage potential in oceanic pools and thus its export has implications for the fate and residence time of terrigenous organic carbon (OC). In contrast to bulk DOC, there is limited knowledge of the environmental factors that control riverine fluxes of DBC. We thus completed a comprehensive assessment of the factors controlling DBC export in tropical rivers with catchments distributed across environmental gradients of hydrology, topography, climate and soil properties. Generalised linear models explained 70% and 64% of the observed variance in DOC and DBC concentrations, respectively. DOC and DBC concentrations displayed coupled responses to the dominant factors controlling their riverine export (soil moisture; catchment slope, and; catchment stocks of OC or BC, respectively) but varied divergently across gradients of temperature and soil properties. DBC concentrations also varied strongly with aerosol BC deposition rate, indicating further potential for deviation of DBC fluxes from those of DOC due to secondary inputs of DBC from this unmatched source. Overall, this study identifies the specific drivers of BC dynamics in river catchments and fundamentally enhances our understanding of refractory DOC export to the global oceans.
Abstract.
Yuan W, Zheng Y, Piao S, Ciais P, Lombardozzi D, Wang Y, Ryu Y, Chen G, Dong W, Hu Z, et al (2019). Increased atmospheric vapor pressure deficit reduces global vegetation growth.
Science Advances,
5(8).
Abstract:
Increased atmospheric vapor pressure deficit reduces global vegetation growth
Atmospheric vapor pressure deficit (VPD) is a critical variable in determining plant photosynthesis. Synthesis of four global climate datasets reveals a sharp increase of VPD after the late 1990s. In response, the vegetation greening trend indicated by a satellite-derived vegetation index (GIMMS3g), which was evident before the late 1990s, was subsequently stalled or reversed. Terrestrial gross primary production derived from two satellite-based models (revised EC-LUE and MODIS) exhibits persistent and widespread decreases after the late 1990s due to increased VPD, which offset the positive CO2 fertilization effect. Six Earth system models have consistently projected continuous increases of VPD throughout the current century. Our results highlight that the impacts of VPD on vegetation growth should be adequately considered to assess ecosystem responses to future climate conditions.
Abstract.
Song X, Gao Y, Green SM, Wen X, Dungait JAJ, Xiong B, Quine TA, He N (2019). Rainfall driven transport of carbon and nitrogen along karst slopes and associative interaction characteristic.
Journal of Hydrology,
573, 246-254.
Abstract:
Rainfall driven transport of carbon and nitrogen along karst slopes and associative interaction characteristic
Transportation of carbon and nitrogen during rainfall events is highly important within karst ecosystems and has particular relevance to understand decoupling relation between carbon and nitrogen cycles. The ability of the karst ecosystem to sequester carbon is currently unknown but has potential to be an important residual terrestrial carbon sink. We hypothesis that the runoff response to rainfall events will vary according to whether the slope belongs to karst area, and carbon and nitrogen have imbalanced outputs response to runoff. Hence, a series of in-situ simulated rainfall experiments at three sites (two karst slopes with different carbonate matrixes and one non-karst slope without a carbonate matrix) were conducted in a typical karst zone in southwest China. We measured runoff discharge, and dissolved carbon and nitrogen during the experiments. The results show that the total runoff discharge increased positively with rainfall intensity, with the carbonate matrix making an important contribution to rainfall reallocation. The dissolved carbon loss from runoff plots is much higher than the dissolved nitrogen, with the dissolved C/N revealing the decoupling relation of carbon and nitrogen cycles in this critical karst zone. This initial carbon migrated by runoff at catchment scale is critical to carbon budgets in rivers. Furthermore, nitrogen leaching from the system is crucial as a nitrogen shortage at karst area in southwest China.
Abstract.
Wang X, Quine TA, Zhang H, Tian G, Yuan W (2019). Redistribution of Soil Organic Carbon Induced by Soil Erosion in the Nine River Basins of China.
Journal of Geophysical Research: Biogeosciences,
124(4), 1018-1031.
Abstract:
Redistribution of Soil Organic Carbon Induced by Soil Erosion in the Nine River Basins of China
Global soil erosion redistributes a large amount of soil organic carbon (SOC) and is potential to significantly change the terrestrial carbon budget. However, there are large uncertainties in the redistribution of SOC within the terrestrial and aquatic ecosystems. Based on two national survey data sets on soil erosion and sediment measurements from hydrological stations, this study estimated the redistribution of sediment and SOC in the nine river basins of China during 1995–1996 and 2010–2012. Over these two periods, 3.55–4.50 Pg of soil and 68.42–77.32 Tg C of SOC were eroded each year. For the SOC budget, on average 57% and 47% of the eroded SOC was deposited over land, 25% and 44% was deposited in the channel, and 18% and 8% was delivered into the sea during 1995–1996 and 2010–2012, respectively. Compared with the corresponding magnitudes during 1995–1996, the eroded SOC, the SOC deposited over land, and the SOC discharged into the sea decreased during 2010–2012, and only the SOC deposited into the river channel increased (from 19.5 to 30.1 Tg C yr−1). The changes in SOC deposition in the channel of the Yangtze River and the Yellow River basins demonstrate that the influence of human activities is extensive. Our results show that the erosion-induced redistribution of SOC alters the carbon budget of China.
Abstract.
Liu H, Jiang Z, Dai J, Wu X, Peng J, Wang H, Meersmans J, Green SM, Quine TA (2019). Rock crevices determine woody and herbaceous plant cover in the karst critical zone.
Science China Earth Sciences,
62(11), 1756-1763.
Abstract:
Rock crevices determine woody and herbaceous plant cover in the karst critical zone
The study of the critical zones (CZs) of the Earth link the composition and function of aboveground vegetation with the characteristics of the rock layers, providing a new way to study how the unique rock and soil conditions in karst regions affect the aboveground vegetation. Based on survey results of the rocks, soils and vegetation in the dolomite and limestone distribution areas in the karst area of central Guizhou, it was found that woody plant cover increases linearly with the number of cracks with a width of more than 1 mm, while the cover of herbaceous plants shows the opposite trend (p
Abstract.
Guo Z, Zhang X, Green SM, Dungait JAJ, Wen X, Quine TA (2019). Soil enzyme activity and stoichiometry along a gradient of vegetation restoration at the Karst Critical Zone Observatory in Southwest China.
Land Degradation and Development,
30(16), 1916-1927.
Abstract:
Soil enzyme activity and stoichiometry along a gradient of vegetation restoration at the Karst Critical Zone Observatory in Southwest China
The “Grain for Green Programme” was implemented in the 1990s as a solution to the extreme degradation of karst landscapes that cover one-third of China, largely caused by decades of poorly managed intensive agriculture. The recovery of soil functions is key to the success of ecosystem regeneration of abandoned croplands where the carbon (C) and nutrient cycles have been severely perturbed by cultivation. However, an ecological ‘tipping point’ beyond which soil functions are unrecoverable in manageable timescales may have been passed in the fragile, subtropical karst ecosystem. The aim of this study was to use the activity of key enzymes for C, nitrogen (N), and phosphorus (P) acquisition in the soil as a proxy for the biological response to vegetation restoration after agricultural abandonment in a severely degraded karst catchment at the Karst Critical Zone Observatory in Guizhou Province. In 2016, a space-for-time approach was used to establish a chronosequence of vegetation recovery: sloping cropland
Abstract.
Green SM, Dungait JAJ, Tu C, Buss HL, Sanderson N, Hawkes SJ, Xing K, Yue F, Hussey VL, Peng J, et al (2019). Soil functions and ecosystem services research in the Chinese karst Critical Zone.
Chemical Geology,
527Abstract:
Soil functions and ecosystem services research in the Chinese karst Critical Zone
Covering extensive parts of China, karst is a critically important landscape that has experienced rapid and intensive land use change and associated ecosystem degradation within only the last 50 years. In the natural state, key ecosystem services delivered by these landscapes include regulation of the hydrological cycle, nutrient cycling and supply, carbon storage in soils and biomass, biodiversity and food production. Intensification of agriculture since the late-20th century has led to a rapid deterioration in Critical Zone (CZ) state, evidenced by reduced crop production and rapid loss of soil. In many areas, an ecological ‘tipping point’ appears to have been passed as basement rock is exposed and ‘rocky desertification’ dominates. This paper reviews contemporary research of soil processes and ecosystems service delivery in Chinese karst ecosystems, with an emphasis on soil degradation and the potential for ecosystem recovery through sustainable management. It is clear that currently there is limited understanding of the geological, hydrological and ecological processes that control soil functions in these landscapes, which is critical for developing management strategies to optimise ecosystem service delivery. This knowledge gap presents a classic CZ scientific challenge because an integrated multi-disciplinary approach is essential to quantify the responses of soils in the Chinese karst CZ to extreme anthropogenic perturbation, to develop a mechanistic understanding of their resilience to environmental stressors, and thereby to inform strategies to recover and maintain sustainable soil function.
Abstract.
Hao Z, Gao Y, Ma M, Green SM, Wang J, Song X, Dungait JAJ, Johnes PJ, Xiong B, Quine TA, et al (2019). Using δ <sup>13</sup> C to reveal the importance of different water transport pathways in two nested karst basins, Southwest China.
Journal of Hydrology,
571, 425-436.
Abstract:
Using δ 13 C to reveal the importance of different water transport pathways in two nested karst basins, Southwest China
This study used carbon (C) isotope sourcing to determine transport processes of dissolved inorganic carbon (DIC) from the land surface to river catchments in Southwest China. Both nested karst watersheds investigated (Chenqi and Houzhai) are representative of typical karst landform environments (e.g. primary forest, secondary forest, and farmland). We measured DIC concentrations and the δ 13 C values of rainfall, river water, groundwater, soil, and plants. To do so, we used IsoSource (a Visual Basic program) to determine source partitioning over time (seasonal) and across the two nested watersheds. In 2017, the mean DIC concentration was 0.06 ± 0.03 mmol L −1 and the rainfall δ 13 C DIC value was −14.4‰ ±1.9‰. We found similar DIC concentrations in the surface and groundwater of both watersheds, ranging from 0.20 to 0.71 mmol L −1 (seasonal) and from −3.7‰ to −9.4‰ (δ 13 C DIC ) in the Chenqi catchment and from 0.33 to 0.60 mmol L −1 (seasonal) and from −10.3‰ to −6‰ (δ 13 C DIC ) in the Houzhai watershed. The average δ 13 C values of soil and local plants were −24.6 ± 1.4‰ and −28.9 ± 1.2‰ in the Chenqi catchment and −25.8 ± 0.9‰ and −27.2 ± 1.8‰ in Houzhai watershed, respectively. In addition, carbonate bedrock and groundwater were the main sources of surface water in the Chenqi and Houzhai nested watersheds, both being greater than 30%. Source percentages were ∼20% from atmospheric deposition and ∼10% from soil. Furthermore, HCO 3− was the predominant form of DIC (pH values > 8), and the contribution rates of dissolved carbonate minerals (HCO 3− ) were approximately 10.4% and 19.6% in the Chenqi catchment and the Houzhai watershed, respectively.
Abstract.
2018
Tu C, Liu C, Quine TA, Jones MW, Liu T, Li L, Liu W (2018). Dynamics of soil organic carbon following land-use change: insights from stable C-isotope analysis in black soil of Northeast China.
Acta Geochimica,
37(5), 746-757.
Abstract:
Dynamics of soil organic carbon following land-use change: insights from stable C-isotope analysis in black soil of Northeast China
Intensive soil tillage is a significant factor in soil organic matter decline in cultivated soils. Both cultivation abandonment and foregoing tillage have been encouraged in the past 30 years to reduce greenhouse gas emissions and soil erosion. However, the dynamic processes of soil organic carbon (SOC) in areas of either continuous cultivation or abandonment remain unclear and inconsistent. Our aims were to assess and model the dynamic processes of SOC under continuous tillage and after cultivation abandonment in the black soil of Northeast China. Soil profiles were collected of cultivated or abandoned land with cultivation history of 0–100 years. An isotope mass balance equation was used to calculate the proportion of SOC derived from corn debris (C4) and from natural vegetation (C3) to deduce the dynamic process. Approximately 40% of SOC in the natural surface soil (0–10 cm) was eroded in the first 5 years of cultivation, increasing to about 75% within 40 years, before a slow recovery. C4 above 30 cm soil depth increased by 4.5%–5% or 0.11–0.12 g·kg−1 on average per year under continuous cultivation, while it decreased by approximately 0.34% annually in the surface soil after cultivation abandonment. The increase in the percentage of C4 was fitted to a linear equation with given intercepts in the upper 30 cm of soil in cultivated land. A significant relationship between the change of C4 and time was found only in the surface soil after abandonment of cultivation. These results demonstrate the loss and accumulation of corn-derived SOC in surface black soil of Northeast China under continuous tillage or cultivation abandonment.
Abstract.
Ma M, Gao Y, Song X, Green SM, Xiong B, Dungait JAJ, Peng T, Quine TA, Wen X, He N, et al (2018). Migration and leaching characteristics of base cation: indicating environmental effects on soil alkalinity in a karst area.
Environ Sci Pollut Res Int,
25(21), 20899-20910.
Abstract:
Migration and leaching characteristics of base cation: indicating environmental effects on soil alkalinity in a karst area.
In karst areas, rock dissolution often results in the development of underground networks, which act as subterranean pathways for rapid water and nutrient (and possibly soil) loss during precipitation events. Loss of soluble nutrients degrades surface soils and decreases net primary productivity, so it is important to establish flow pathways and quantify nutrient loss during rainfall events of different magnitudes. We conducted a simulated rainfall experiment in karst and nonkarst areas to compare the concentration of nutrients in surface and subsurface flow water and effects on soil alkalinity in three lithologic soil formations under five different rainfall intensity treatments. Compared with the nonkarst area, the runoff in subsurface flows and the proportion of nutrient loss in the subsurface flow are larger in the karst area and less affected by rain intensity. The maximum loss loads of calcium (Ca2+) and magnesium (Mg2+) ions were 32.9 and 19.8 kg ha-1, respectively. With the estimate of base cation loss loads in the China southern karst area under the rainfall intensity of 45 mm h-1, more than 80% of the base cation loss load occurred in the limestone karst area. Although the alkalinity leaching value in nonkarst was similar to that in the karst area under simulated rainfall conditions, its impact on the ecological environment was quite different.
Abstract.
Author URL.
Sankar M, Green SM, Mishra PK, Snoalv JTC, Sharma NK, Karthikeyan K, Somasundaram J, Kadam DM, Dinesh D, Kumar S, et al (2018). Nationwide soil erosion assessment in India using radioisotope tracers Cs-137 and Pb-210: the need for fallout mapping.
CURRENT SCIENCE,
115(3), 388-390.
Author URL.
Li D, Zhang X, Green SM, Dungait JAJ, Wen X, Tang Y, Guo Z, Yang Y, Sun X, Quine TA, et al (2018). Nitrogen functional gene activity in soil profiles under progressive vegetative recovery after abandonment of agriculture at the Puding Karst Critical Zone Observatory, SW China.
Soil Biology and Biochemistry,
125, 93-102.
Abstract:
Nitrogen functional gene activity in soil profiles under progressive vegetative recovery after abandonment of agriculture at the Puding Karst Critical Zone Observatory, SW China
At the end of the 20th century, China launched the ‘Grain-for-Green’ Project (GGP) that recommended the abandonment of low-yielding sloping farmland (>15°) prone to soil degradation by erosion, to allow recovery through natural vegetative regeneration. The effect of this policy on soil nitrogen (N) cycling, as fertilization applications are also withdrawn after abandonment, is poorly understood. A space-for-time approach was applied to investigate the responses of nitrogen functional genes (NFGs) in soil profiles (surface to bedrock) associated with progressive vegetative recovery (sloping farmland > recently abandoned sloping farmland > secondary forest > primary forest) at the Puding Karst Critical Zone Observatory in Guizhou province, southwest China. Coincident soil chemical properties (dissolved organic carbon (DOC), nitrate (NO3--N), ammonium (NH4+-N), available inorganic phosphorus (AP), soil organic carbon (SOC), total nitrogen (TN) and total phosphorus (TP)) were also quantified. We found that the absolute abundance of NFGs significantly varied according to the phase of vegetation recovery, and that concentrations of AP and NO3--N were the best explanatory variables. The external N from fertilizer application promoted the absolute abundances of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) in sloping farmland. The relative abundances of chiA (associated with decomposition) increased with soil depth across all vegetation recovery phases. The relative abundances of chiA and nifH (associated with N fixation) accounted for the largest proportion (58–72%) of the measured NFGs, indicating that active N-acquisition increased along the vegetation recovery gradient. The ratios of (chiA + nifH)/(AOA + AOB) and the sums of (nirK + nirS) were larger in the forest soil than those of sloping farmland and abandoned sloping farmland, implying a greater capacity for N storage potential, though accompanied by increased gas N emission potential, in the karst forest ecosystems. Our results provide a new and comprehensive understanding of soil N cycling potentials at the microscale in degraded and recovering karst ecosystems.
Abstract.
Cressey EL, Dungait JAJ, Jones DL, Nicholas AP, Quine TA (2018). Soil microbial populations in deep floodplain soils are adapted to infrequent but regular carbon substrate addition.
Soil Biology and Biochemistry,
122, 60-70.
Abstract:
Soil microbial populations in deep floodplain soils are adapted to infrequent but regular carbon substrate addition
Floodplain soils provide an important link in the land-ocean aquatic continuum. Understanding microbial activity in these soils, which can be many metres deep, is a key component in our understanding of the role of floodplains in the carbon (C) cycle. We sampled the mineral soil profile to 3 m depth from two floodplain sites under long-term pasture adjacent to the river Culm in SW England, UK. Soil chemistry (C, nitrogen (N), phosphorus (P), soil microbial biomass (SMB), moisture content) and soil solution (pH, dissolved organic C (DOC) and N, nitrate, ammonium, water extractable P) were analysed over the 3 m depth in 6 increments: 0.0–0.2, 0.2–0.7, 1.0–1.5, 1.5–2.0, 2.0–2.5, and 2.5–3.0 m. 14C-glucose was added to the soil and the evolution of 14CO2 measured during a 29 d incubation. From soil properties and 14C-glucose mineralisation, three depth groups emerged, with distinct turnover times extrapolated from initial k1 mineralisation rate constants of 2 h (topsoil 0.0–0.2 m), 4 h (subsoil 0.2–0.7 m), and 11 h (deep subsoil 1.0–3.0 m). However, when normalised by SMB, k1 rate constants had no significant differences across all depths. Deep subsoil had a 2 h lag to reach maximal 14CO2 production whereas the topsoil and subsoil (0.2–0.7 m) achieved maximum mineralisation rates immediately. SMB decreased with depth, but only to half of the surface population, with the proportion of SMB-C to total C increasing from 1% in topsoil to 15% in deep subsoil (>1.0 m). The relatively large SMB concentration and rapid mineralisation of 14C-glucose suggests that DOC turnover in deep soil horizons in floodplains is limited by access to biologically available C and not the size of the microbial population.
Abstract.
Glendell M, Jones R, Dungait JAJ, Meusburger K, Schwendel AC, Barclay R, Barker S, Haley S, Quine TA, Meersmans J, et al (2018). Tracing of particulate organic C sources across the terrestrial-aquatic continuum, a case study at the catchment scale (Carminowe Creek, southwest England).
Science of the Total Environment,
616-617, 1077-1088.
Abstract:
Tracing of particulate organic C sources across the terrestrial-aquatic continuum, a case study at the catchment scale (Carminowe Creek, southwest England)
Soils deliver crucial ecosystem services, such as climate regulation through carbon (C) storage and food security, both of which are threatened by climate and land use change. While soils are important stores of terrestrial C, anthropogenic impact on the lateral fluxes of C from land to water remains poorly quantified and not well represented in Earth system models. In this study, we tested a novel framework for tracing and quantifying lateral C fluxes from the terrestrial to the aquatic environment at a catchment scale. The combined use of conservative plant-derived geochemical biomarkers n-alkanes and bulk stable δ13C and δ15N isotopes of soils and sediments allowed us to distinguish between particulate organic C sources from different land uses (i.e. arable and temporary grassland vs. permanent grassland vs. riparian woodland vs. river bed sediments) (p < 0.001), showing an enhanced ability to distinguish between land use sources as compared to using just n-alkanes alone. The terrestrial-aquatic proxy (TAR) ratio derived from n-alkane signatures indicated an increased input of terrestrial-derived organic matter (OM) to lake sediments over the past 60 years, with an increasing contribution of woody vegetation shown by the C27/C31 ratio. This may be related to agricultural intensification, leading to enhanced soil erosion, but also an increase in riparian woodland that may disconnect OM inputs from arable land uses in the upper parts of the study catchment. Spatial variability of geochemical proxies showed a close coupling between OM provenance and riparian land use, supporting the new conceptualization of river corridors (active river channel and riparian zone) as critical zones linking the terrestrial and aquatic C fluxes. Further testing of this novel tracing technique shows promise in terms of quantification of lateral C fluxes as well as targeting of effective land management measures to reduce soil erosion and promote OM conservation in river catchments.
Abstract.
2017
Eludoyin AO, Griffith B, Orr RJ, Bol R, Quine TA, Brazier RE (2017). An evaluation of the hysteresis in chemical concentration–discharge (C–Q) relationships from drained, intensively managed grasslands in southwest England.
Hydrological Sciences Journal,
62(8), 1243-1254.
Abstract:
An evaluation of the hysteresis in chemical concentration–discharge (C–Q) relationships from drained, intensively managed grasslands in southwest England
This study examined the hysteresis exhibited in concentration–discharge (C–Q) relationships in the runoff from four hydrologically separated fields (catchments) at an intensively managed grassland. The objectives were to examine C–Q relationships constructed from high-resolution time series of flow, temperature, pH, conductivity, nitrate and turbidity, and their implications for hydrological processes. High-resolution datasets from the quality assured records of the Rothamsted Research North Wyke Farm Platform in the UK were examined using a graphical method and cross-correlation statistics. The study found that storm events based C–Q hysteresis reflects the cross-correlation that is generally hidden in time series analysis of large datasets, and that although Q and water quality variables can be effectively influenced by catchment size, the C–Q relationship is less significantly influenced. The dominant C–Q relationships of the water variables in the study area reflect that saturated overland flow was prevalent during the study period in the catchments, while the CCF results indicate coupled transfer of sediments and solute in the area at lag ≥ 0. EDITOR D. Koutsoyiannis ASSOCIATE EDITOR M. D. Fidelibus.
Abstract.
Janes VJJ, Nicholas AP, Collins AL, Quine TA (2017). Analysis of fundamental physical factors influencing channel bank erosion: results for contrasting catchments in England and Wales.
Environmental Earth Sciences,
76(7).
Abstract:
Analysis of fundamental physical factors influencing channel bank erosion: results for contrasting catchments in England and Wales
Channel bank erosion processes are controlled by numerous factors and as such are both temporally and spatially variable. The significance of channel bank erosion to the sediment budget is difficult to quantify without extensive fieldwork/data analysis. In this study, the importance of key physical factors controlling channel bank erosion, including channel slope, upstream catchment area, channel confinement, and sinuosity, was explored using regression analysis. The resulting analysis can be used in practical studies to provide a first approximation of bank erosion rates (in catchments similar to those investigated). A data set of channel bank erosion rates covering eight contrasting river catchments across England and Wales, over a time period of up to 150 years, was created using a modified GIS methodology. The best predictors were found to be upstream area, channel confinement, and sinuosity with respect to dimensionless width-averaged retreat rates (m m−1 yr−1). Notwithstanding these relationships, the results highlight the variability of the magnitude of sediment production by channel bank erosion both within and between catchments.
Abstract.
Jones MW, Quine TA, de Rezende CE, Dittmar T, Johnson B, Manecki M, Marques JSJ, de Aragão LEOC (2017). Do Regional Aerosols Contribute to the Riverine Export of Dissolved Black Carbon?.
Journal of Geophysical Research: Biogeosciences,
122(11), 2925-2938.
Abstract:
Do Regional Aerosols Contribute to the Riverine Export of Dissolved Black Carbon?
AbstractThe fate of black carbon (BC), a stable form of thermally altered organic carbon produced during biomass and fuel combustion, remains an area of uncertainty in the global carbon cycle. The transfer of photosynthetically derived BC into extremely long‐term oceanic storage is of particular significance and rivers are the key linkage between terrestrial sources and oceanic stores. Significant fluvial fluxes of dissolved BC to oceans result from the slow release of BC from degrading charcoal stocks; however, these fluvial fluxes may also include undetermined contributions of aerosol BC, produced by biomass and fossil fuel combustion, which are deposited in river catchments following atmospheric transport. By investigation of the Paraíba do Sul River catchment in Southeast Brazil we show that aerosol deposits can be substantial contributors to fluvial fluxes of BC. We derived spatial distributions of BC stocks within the catchment associated with soil charcoal and with aerosol from both open biomass burning and fuel combustion. We then modeled the fluvial concentrations of dissolved BC (DBC) in scenarios with varying rates of export from each stock. We analyzed the ability of each scenario to reproduce the variability in DBC concentrations measured in four data sets of river water samples collected between 2010 and 2014 and found that the best performing scenarios included a 5–18% (135–486 Mg DBC year−1) aerosol contribution. Our results suggest that aerosol deposits of BC in river catchments have a shorter residence time in catchments than charcoal BC and, therefore, contribute disproportionately (with respect to stock magnitude) toward fluvial fluxes of BC.
Abstract.
Quine T, Guo D, Green SM, Tu C, Hartley I, Zhang X, Dungait J, Wen X, Song Z, Liu H, et al (2017). Ecosystem service delivery in Karst landscapes: anthropogenic perturbation and recovery.
Acta Geochimica,
36(3), 416-420.
Abstract:
Ecosystem service delivery in Karst landscapes: anthropogenic perturbation and recovery
Covering extensive parts of China, Karst landscapes are exceptional because rapid and intensive land use change has caused severe ecosystem degradation within only the last 50 years. The twentieth century intensification in food production through agriculture has led to a rapid deterioration of soil quality, evidenced in reduced crop production and rapid loss of soil. In many areas, a tipping point appears to have been passed as basement rock is exposed and ‘rocky desertification’ dominates. Through the establishment of the “Soil processes and ecological services in the karst critical zone of SW China” (SPECTRA) Critical Zone Observatory (CZO) we will endevaour to understand the fundmental processes involved in soil production and erosion, and investigate the integrated geophysical-geochemical-ecological responses of the CZ to perturbations. The CZ spans a gradient from undisturbed natural vegetation through human perturbed landscapes. We seek to understand the importance of heterogeneity in surface and below-ground morphology and flow pathways in determining the spatial distribution of key stocks (soil, C, vegetation, etc.) and their control on ecosystem service delivery. We will assess the extent to which the highly heterogeneous critical zone resources can be restored to enable sustainable delivery of ecosystem services. This paper presents the CZO design and initial assessment of soil and soil organic carbon stocks and evidence for their stability based on caesium-137 (137Cs) data.
Abstract.
Song X, Gao Y, Green SM, Dungait JAJ, Peng T, Quine TA, Xiong B, Wen X, He N (2017). Nitrogen loss from karst area in China in recent 50 years: An in-situ simulated rainfall experiment's assessment.
Ecology and Evolution,
7(23), 10131-10142.
Abstract:
Nitrogen loss from karst area in China in recent 50 years: An in-situ simulated rainfall experiment's assessment
Karst topography covers more than 1/3 of the People's Republic of China in area. The porous, fissured, and soluble nature of the underlying karst bedrock (primarily dolomite and limestone) leads to the formation of underground drainage systems. Karst conduit networks dominate this system, and rainfall takes a crucial role on water cycle at China karst area. Nitrogen loss from the karst system is of particular concern, with regard to nutrient use efficiency as well as water quality, as much of the karst system, including steeply sloping terrain, is used for intensive agriculture. We use simulated rainfall experiments to determine the relationship between rainfall and nitrogen loss at typical karst slope land and then estimate nitrogen loss from the karst soil. The results show that both surface runoff and subsurface runoff have a significant linear correlation with rainfall at all studied sites. Subsurface runoff is larger than surface runoff at two karst sites, while the opposite is true at the non-karst site. Exponential function satisfactorily described the correlation between rainfall and nitrogen concentrations in runoff. Nitrates accounted for 60%–95% of the dissolved nitrogen loss (DN, an index of N-loss in this research). The estimated annual N-loss load varies between 1.05 and 1.67 Tg N/year in the whole karst regions of China from 1961 to 2014. Approximately, 90% of the N-loss load occurred during the wet season, and 90% of that passed through the subsurface. Understanding the processes and estimating N-loss is highly valuable in determining long-term soil security and sustainability in karst regions.
Abstract.
Navas A, Quine TA, Walling DE, Gaspar L, Quijano L, Lizaga I (2017). Relating Intensity of Soil Redistribution to Land Use Changes in Abandoned Pyrenean Fields Using Fallout Caesium-137.
Land Degradation and Development,
28(7), 2017-2029.
Abstract:
Relating Intensity of Soil Redistribution to Land Use Changes in Abandoned Pyrenean Fields Using Fallout Caesium-137
Fallout caesium-137 has been used to trace soil redistribution in abandoned fields located in the Central Spanish Pyrenees. A total of 28 fields with different lengths, slope angles and time since abandonment were selected on a representative south-facing slope of the Estarrún valley. The local reference inventory and the magnitude and spatial distribution of 137Cs inventories within these fields were documented and used as a basis for assessing patterns of soil redistribution. The local reference inventory was estimated to be 4,500 Bqm−2. Within the fields, the average 137Cs inventory at the top of the slope was 3,920 Bqm−2, and accumulation of soil at the bottom of the slopes was demonstrated by an average 137Cs inventory of 5,320 Bqm−2. Deviations from the reference inventory were highest for fields with the longest slopes that had been abandoned for less than 30 years. Here, increases in the 137Cs inventory, relative to the reference inventory, in excess of 20% were found at the bottom of the slopes. Considering all the fields and all geomorphic positions within the fields, the greatest 137Cs losses and gains were found in the fields with the longest duration of abandonment, indicating more intense soil redistribution. Irrespective of the timing of abandonment, the ranges of 137Cs inventories in the fields were found to be proportional to the water erosion index. The 137Cs technique demonstrated that patterns of sediment redistribution were closely related to the topographic and physiographic characteristics of the slopes. Copyright © 2017 John Wiley & Sons, Ltd.
Abstract.
Quine T, Wykes M (2017). University challenge. Economist (United Kingdom), 413(9051).
2016
Meersmans J, Arrouays D, Van Rompaey AJJ, Pagé C, De Baets S, Quine TA (2016). Future C loss in mid-latitude mineral soils: climate change exceeds land use mitigation potential in France.
Sci Rep,
6Abstract:
Future C loss in mid-latitude mineral soils: climate change exceeds land use mitigation potential in France.
Many studies have highlighted significant interactions between soil C reservoir dynamics and global climate and environmental change. However, in order to estimate the future soil organic carbon sequestration potential and related ecosystem services well, more spatially detailed predictions are needed. The present study made detailed predictions of future spatial evolution (at 250 m resolution) of topsoil SOC driven by climate change and land use change for France up to the year 2100 by taking interactions between climate, land use and soil type into account. We conclude that climate change will have a much bigger influence on future SOC losses in mid-latitude mineral soils than land use change dynamics. Hence, reducing CO2 emissions will be crucial to prevent further loss of carbon from our soils.
Abstract.
Author URL.
De Baets S, Van de Weg MJ, Lewis R, Steinberg N, Meersmans J, Quine TA, Shaver GR, Hartley IP (2016). Investigating the controls on soil organic matter decomposition in tussock tundra soil and permafrost after fire.
Soil Biology and Biochemistry,
99, 108-116.
Abstract:
Investigating the controls on soil organic matter decomposition in tussock tundra soil and permafrost after fire
Rapid warming in Arctic ecosystems is resulting in increased frequency of disturbances such as fires, changes in the distribution and productivity of different plant communities, increasing thaw depths in permafrost soils and greater nutrient availability, especially nitrogen. Individually and collectively, these factors have the potential to strongly affect soil C decomposition rates, with implications for the globally significant stores of carbon in this region. However, considerable uncertainty remains regarding how C decomposition rates are controlled in Arctic soils. In this study we investigated how temperature, nitrogen availability and labile C addition affected rates of CO2 production in short (10-day for labile C) and long-term (1.5 year for temperature and N) incubations of samples collected from burned and unburned sites in the Anaktuvuk river burn on the North Slope of Alaska from different depths (organic horizon, mineral horizon and upper permafrost). The fire in this region resulted in the loss of several cms of the organic horizon and also increased active layer depth allowing the impacts of four years of thaw on deeper soil layers to be investigated. Respiration rates did not decline substantially during the long-term incubation, although decomposition rates per unit organic matter were greater in the organic horizon. In the mineral and upper permafrost soil horizons, CO2 production was more temperature sensitive, while N addition inhibited respiration in the mineral and upper permafrost layers, especially at low temperatures. In the short-term incubations, labile C additions promoted the decomposition of soil organic matter in the mineral and upper permafrost samples, but not in the organic samples, with this effect being lost following N addition in the deeper layers. These results highlight that (i) there are substantial amounts of labile organic matter in these soils (ii), the organic matter stored in mineral and upper permafrost in the tussock tundra is less readily decomposable than in the organic horizon, but that (iii) its decomposition is more sensitive to changes in temperature and that (iv) microbial activity in deeper soil layers is limited by labile C availability rather than N. Collectively, these results indicate that in addition to the loss of C by combustion of organic matter, increasing fire frequency also has the potential to indirectly promote the release of soil C to the atmosphere in the years following the disturbance.
Abstract.
Meersmans J, Van Weverberg K, De Baets S, De Ridder F, Palmer SJ, van Wesemael B, Quine TA (2016). Mapping mean total annual precipitation in Belgium, by investigating the scale of topographic control at the regional scale.
Journal of Hydrology,
540, 96-105.
Abstract:
Mapping mean total annual precipitation in Belgium, by investigating the scale of topographic control at the regional scale
Accurate precipitation maps are essential for ecological, environmental, element cycle and hydrological models that have a spatial output component. It is well known that topography has a major influence on the spatial distribution of precipitation and that increasing topographical complexity is associated with increased spatial heterogeneity in precipitation. This means that when mapping precipitation using classical interpolation techniques (e.g. regression, kriging, spline, inverse distance weighting, etc.), a climate measuring network with higher spatial density is needed in mountainous areas in order to obtain the same level of accuracy as compared to flatter regions. In this study, we present a mean total annual precipitation mapping technique that combines topographical information (i.e. elevation and slope orientation) with average total annual rain gauge data in order to overcome this problem. A unique feature of this paper is the identification of the scale at which topography influences the precipitation pattern as well as the direction of the dominant weather circulation. This method was applied for Belgium and surroundings and shows that the identification of the appropriate scale at which topographical obstacles impact precipitation is crucial in order to obtain reliable mean total annual precipitation maps. The dominant weather circulation is determined at 260°. Hence, this approach allows accurate mapping of mean annual precipitation patterns in regions characterized by rather high topographical complexity using a climate data network with a relatively low density and/or when more advanced precipitation measurement techniques, such as radar, aren't available, for example in the case of historical data.
Abstract.
2015
Li Y, Quine TA, Yu HQ, Govers G, Six J, Gong DZ, Wang Z, Zhang YZ, Van Oost K (2015). Sustained high magnitude erosional forcing generates an organic carbon sink: Test and implications in the Loess Plateau, China.
Earth and Planetary Science Letters,
411, 281-289.
Abstract:
Sustained high magnitude erosional forcing generates an organic carbon sink: Test and implications in the Loess Plateau, China
© 2014 Elsevier B.V. Humans are now the most important geomorphic agent on the planet and accelerated erosion in agricultural landscapes results in high magnitude lateral organic carbon (OC) fluxes and significant perturbation of the land-ocean carbon flux. Nevertheless, the net effect of these lateral carbon fluxes on the C cycle is poorly constrained and there is no consensus as to whether they drive a net source or net sink of atmospheric CO2. Here, we test the hypothesis that, under sustained erosional forcing, soil carbon stocks on hillslopes reach a new equilibrium state in which all carbon exported with erosion is replaced; and, therefore, erosion results in a net sink for atmospheric CO2 at the scale of eroding hillslopes. The evidence from our study site, in the Loess Plateau of China, is consistent with this hypothesis. Despite net export of OC equivalent to ca. 10% NPP, we found that all of the eroded OC was replaced and, therefore, that the sink strength was equal to the C export rate. This sets the upper limit of the erosion-induced sink term at the scale of whole watershed. The fate of the exported carbon in reservoirs, floodplains, riverbeds and the ocean ultimately controls the watershed-scale sink strength. Nevertheless, the full replacement observed here suggests that erosion does not induce a C source, irrespective of the fate of the exported carbon, at least for high-input agricultural systems. Finally, we propose that assessment of the C cycle perturbation associated with erosion-induced lateral C fluxes must be made an integral part of accounting mechanisms for climate change mitigation strategies that are based on land use change and C sequestration in terrestrial environments.
Abstract.
2014
Wang Z, Van Oost K, Lang A, Quine T, Clymans W, Merckx R, Notebaert B, Govers G (2014). The fate of buried organic carbon in colluvial soils: a long-term perspective.
Biogeosciences,
11(3), 873-883.
Abstract:
The fate of buried organic carbon in colluvial soils: a long-term perspective
Colluvial soils are enriched in soil organic carbon (SOC) in comparison to the soils of upslope areas due to the deposition and progressive burial of SOC. This burial of SOC has important implications for the global carbon cycle, but the long-term dynamics of buried SOC remain poorly constrained. We addressed this issue by determining the SOC burial efficiency (i.e. the fraction of originally deposited SOC that is preserved in colluvial deposits) of buried SOC as well as the SOC stability in colluvial soils. We quantified the turnover rate of deposited SOC by establishing sediment and SOC burial chronologies. The SOC stability was derived from soil incubation experiments and the δ13C values of SOC. The C burial efficiency was found to decrease with time, reaching a constant ratio of approximately 17% by about 1000-1500 yr post-burial. This decrease is attributed to the increasing recalcitrance of the remaining buried SOC with time and a less favourable environment for SOC decomposition with increasing depth. Buried SOC in colluvial profiles was found to be more stable and degraded in comparison to SOC sampled at the same depth at a stable reference location. This is due to the preferential mineralisation of the labile fraction of the deposited SOC. Our study shows that SOC responds to burial over a centennial timescale; however, more insight into the factors controlling this response is required to fully understand how this timescale may vary, depending on specific conditions such as climate and depositional environment. © Author(s) 2014. CC Attribution 3.0 License.
Abstract.
Greenwood P, Walling DE, Quine TA (2014). Using caesium-134 and cobalt-60 as tracers to assess the remobilization of recently-deposited overbank-derived sediment on river floodplains during subsequent inundation events.
Earth Surface Processes and Landforms,
39(2), 228-244.
Abstract:
Using caesium-134 and cobalt-60 as tracers to assess the remobilization of recently-deposited overbank-derived sediment on river floodplains during subsequent inundation events
River floodplains act as sinks for fine-sediment and sediment-associated contaminants. Increasing recognition of their environmental importance has necessitated a need for an improved understanding of the fate and residence times of overbank sediment deposits over a broad range of timescales. Most existing investigations have focused on medium-term accretion rates, which represents net deposition from multiple flood events over several decades. In contrast, the fate of recently-deposited sediment during subsequent overbank events has received only limited attention. This paper presents a novel tracing-technique for documenting the remobilization of recent overbank sediment on river floodplains during subsequent inundation events, using the artificial radionuclides, caesium-134 (134Cs) and cobalt-60 (60Co). The investigation was conducted within floodplains of the Rivers Taw and Culm in Devon, UK. Small quantities of fine-sediment (< 63μm dia.), pre-labelled with known activities of either 134Cs or 60Co, were deposited at 15 locations across each floodplain. Surface inventories, measured before and after three consecutive flood events, were used to estimate sediment loss (in g m-2). Significant reductions provided evidence of the remobilization of the labelled sediment by inundating floodwaters. Spatial variations in remobilization were related to localized topography. Sediment remobilized during the first two events for the River Taw floodplain were equivalent to 63·8% and 11·9%, respectively, of the original mass. Equivalent values for the River Culm floodplain were 49·6% and 12·5%, respectively, of the original mass. Sediment loss during the third event proved too small to be attributed to remobilization by overbank floodwaters. After the third event, a mean of 22·5% and 35·2% of the original mass remained on the Taw and Culm floodplains, respectively. These results provide evidence of the storage of the remaining sediment. The findings highlight the importance of remobilization of recently-deposited sediment on river floodplains during subsequent overbank events and demonstrate the potential of the tracing-technique. © 2013 John Wiley & Sons, Ltd.
Abstract.
2013
Meersmans J, Martin MP, Lacarce E, Orton TG, De Baets S, Gourrat M, Saby NPA, Wetterlind J, Bispo A, Quine TA, et al (2013). Estimation of Soil Carbon Input in France: an Inverse Modelling Approach.
Pedosphere,
23(4), 422-436.
Abstract:
Estimation of Soil Carbon Input in France: an Inverse Modelling Approach
Development of a quantitative understanding of soil organic carbon (SOC) dynamics is vital for management of soil to sequester carbon (C) and maintain fertility, thereby contributing to food security and climate change mitigation. There are well-established process-based models that can be used to simulate SOC stock evolution; however, there are few plant residue C input values and those that exist represent a limited range of environments. This limitation in a fundamental model component (i.e. C input) constrains the reliability of current SOC stock simulations. This study aimed to estimate crop-specific and environment-specific plant-derived soil C input values for agricultural sites in France based on data from 700 sites selected from a recently established French soil monitoring network (the RMQS database). Measured SOC stock values from this large scale soil database were used to constrain an inverse RothC modelling approach to derive estimated C input values consistent with the stocks. This approach allowed us to estimate significant crop-specific C input values (P < 0.05) for 14 out of 17 crop types in the range from 1.84 ± 0.69 t C ha-1 year-1 (silage corn) to 5.15 ± 0.12 t C ha-1 year-1 (grassland/pasture). Furthermore, the incorporation of climate variables improved the predictions. C input of 4 crop types could be predicted as a function of temperature and 8 as a function of precipitation. This study offered an approach to meet the urgent need for crop-specific and environment-specific C input values in order to improve the reliability of SOC stock prediction. © 2013 Soil Science Society of China.
Abstract.
Evans M, Quine T, Kuhn N (2013). Geomorphology and terrestrial carbon cycling. Earth Surface Processes and Landforms, 38(1), 103-105.
Smith P, Ashmore MR, Black HIJ, Burgess PJ, Evans CD, Quine TA, Thomson AM, Hicks K, Orr HG (2013). REVIEW: the role of ecosystems and their management in regulating climate, and soil, water and air quality.
Journal of Applied Ecology,
50(4), 812-829.
Abstract:
REVIEW: the role of ecosystems and their management in regulating climate, and soil, water and air quality
Ecosystems have a critical role in regulating climate, and soil, water and air quality, but management to change an ecosystem process in support of one regulating ecosystem service can either provide co-benefits to other services or can result in trade-offs. We examine the role of ecosystems in delivering these regulating ecosystem services, using the UK as our case study region. We identify some of the main co-benefits and trade-offs of ecosystem management within, and across, the regulating services of climate regulation, and soil, water and air quality regulation, and where relevant, we also describe interactions with other ecosystem services. Our analysis clearly identifies the many important linkages between these different ecosystem services. However, soil, water and air quality regulation are often governed by different legislation or are under the jurisdiction of different regulators, which can make optimal management difficult to identify and to implement. Policies and legislation addressing air, water and soil are sometimes disconnected, with no integrated overview of how these policies interact. This can lead to conflicting messages regarding the use and management of soil, water and air. Similarly, climate change legislation is separate from that aiming to protect and enhance soil, water and air quality, leading to further potential for policy conflict. All regulating services, even if they are synergistic, may trade off against other ecosystem services. At a policy level, this may well be the biggest conflict. The fact that even individual regulating services comprise multiple and contrasting indicators (e.g. the various components of water quality such as nutrient levels, acidity, pathogens and sediments), adds to the complexity of the challenge. Synthesis and applications. We conclude that although there are some good examples of integrated ecosystem management, some aspects of ecosystem management could be better coordinated to deliver multiple ecosystem services, and that an ecosystem services framework to assess co-benefits and trade-offs would help regulators, policy-makers and ecosystem managers to deliver more coherent ecosystem management strategies. In this way, an ecosystem services framework may improve the regulation of climate, and soil, water and air quality, even in the absence of economic valuation of the individual services. We conclude that although there are some good examples of integrated ecosystem management, some aspects of ecosystem management could be better coordinated to deliver multiple ecosystem services, and that an ecosystem services framework to assess co-benefits and trade-offs would help regulators, policy-makers and ecosystem managers to deliver more coherent ecosystem management strategies. In this way, an ecosystem services framework may improve the regulation of climate, and soil, water and air quality, even in the absence of economic valuation of the individual services. © 2012 British Ecological Society.
Abstract.
De Baets S, Meersmans J, Vanacker V, Quine TA, Van Oost K (2013). Spatial variability and change in soil organic carbon stocks in response to recovery following land abandonment and erosion in mountainous drylands.
Soil Use and Management,
29(1), 65-76.
Abstract:
Spatial variability and change in soil organic carbon stocks in response to recovery following land abandonment and erosion in mountainous drylands
This research investigates the impact of human activities on carbon (C) dynamics in a mountainous and semi-arid environment. Despite the low C status of drylands, soil organic carbon (SOC) is the largest C pool in these systems and therefore may offer significant C sequestration potential in systems recovering from degradation. Nevertheless, quantification of this potential is limited by lack of knowledge concerning the magnitude of and controls on regional SOC stocks. Therefore, this study aimed to (i) investigate the variability of soil organic carbon in relation to recovery period and key soil and topographical variables, and (ii) quantify the effects of recovery period following abandonment on SOC stocks. Soil profiles were sampled in the Sierra de los Filabres (southeast Spain) in different land units along geomorphic and degradation gradients. SOC contents were modelled using recovery period and soil and topographical variables. Sample depth, topographic position, altitude, recovery period and stone content were identified as the main factors for predicting SOC concentrations. SOC stocks in 1 m depth of soil varied between 3.16 and 76.44 t/ha. Recovery period (years since abandonment), topographic position and altitude were used to predict and map SOC stocks in the top 0.2 m. The results show that C accumulates rapidly during the first 10-50 yr following abandonment; thereafter, the stocks evolve towards a steady-state level. The erosion zones in the study area demonstrate greater potential to increase their SOC stocks when abandoned. Deposition zones have greater SOC values, although their C accumulation rate is lower compared with erosional landscapes in the first 10-50 yr following abandonment. Therefore, full understanding of the C sequestration potential of land use change in areas of complex topography requires knowledge of spatial variability in soil properties and in particular SOC. © 2012 the Authors. Journal compilation © 2012 British Society of Soil Science.
Abstract.
De Baets S, Meersmans J, Vanacker V, Quine TA, Van Oost K (2013). Spatial variability and change in soil organic carbon stocks in response to recovery following land abandonment and erosion in mountainous drylands. Soil Use and Management
Doetterl S, Stevens A, van Oost K, Quine TA, van Wesemael B (2013). Spatially-explicit regional-scale prediction of soil organic carbon stocks in cropland using environmental variables and mixed model approaches.
Geoderma,
204-205, 31-42.
Abstract:
Spatially-explicit regional-scale prediction of soil organic carbon stocks in cropland using environmental variables and mixed model approaches
The effects of soil redistribution on the carbon (C) cycle and the need for spatially and depth-explicit C estimates at large scales have recently been receiving growing attention. In eroding agricultural landscapes, C gets transported from erosional to depositional landscape elements forming a heterogeneous pattern in quantity and quality of the distributed carbon. At present, methods and research to characterize this horizontal and vertical variability are either limited to local slope scales or, if applied to larger scales, to surface soil horizons with large uncertainties when extrapolated to deeper layers. In this study, we used soil profile data collected in two zones of differing soil texture (loam and clay-rich soils) in Luxembourg, to calibrate a linear mixed-effect model to predict the 3D soil C stock distribution on a regional scale for cropping systems using a set of spatially-explicit hydrologic, climatic, pedologic and geomorphologic variables. We demonstrate that due to a high spatial variability of C stocks it is mandatory to consider various environmental processes to predict C accurately on a regional scale, especially in deeper soil layers, and to avoid simple depth extrapolation of topsoil C data as has been done earlier in flat landscapes. Using estimates of topsoil C contents derived from hyperspectral remote sensing, we predict spatial patterns of C stocks for cropland on a regional scale and provide new insights into the spatial heterogeneity of soil C storage covering a large area. The variability of C stocks in the two texture zones expressed as values larger or smaller than the mean±standard deviation is hereby lower in the loam zone (26.2%) than in the clay zone (38.7%). We estimate a mean C stock (to 100cm soil depth) of 9.4±3.1kg/m2 for the clay-rich soils and 11.3±2.4kg/m2 for loamy soils. This represents the first regional estimate for C stocks for the research area using continuous spatial explicit datasets. © 2013.
Abstract.
Greenwood P, Walling DE, Quine TA (2013). Using caesium-134 and cobalt-60 as tracers to assess the remobilization of recently-deposited overbank-derived sediment on river floodplains during subsequent inundation events. Earth Surface Processes and Landforms
2012
Evans M, Quine T, Kuhn N (2012). Geomorphology and terrestrial carbon cycling. Earth Surface Processes and Landforms
Smith P, Ashmore MR, Black HIJ, Burgess PJ, Evans CD, Quine TA, Thomson AM, Hicks K, Orr HG (2012). The role of ecosystems and their management in regulating climate, and soil, water and air quality. Journal of Applied Ecology
2010
Nicholas AP, Quine TA (2010). Quantitative assessment of landform equifinality and palaeoenvironmental reconstruction using geomorphic models. Geomorphology, 121(3-4), 167-183.
2009
Nicholas AP, Clarke L, Quine TA (2009). A numerical modelling and experimental study of flow width dynamics on alluvial fans. Earth Surface Processes and Landforms, 34, 1985-1993.
Van Oost K, Cerdan O, Quine TA (2009). Accelerated sediment fluxes by water and tillage erosion on European agricultural land. Earth Sutrface Processes and Landforms
Clarke L, Quine TA, Nicholas AP (2009). An experimental investigation of autogenic behaviour during alluvial fan evolution. Geomorphology, 115, 278-285.
2008
Clarke L, Quine TA, Nicholas AP (2008). An evaluation of the role of physical models in exploring form-process feedbacks in alluvial fans. Sediment Dynamics in Changing Environments.
Clarke LE, Quine TA, Nicholas AP (2008). An evaluation of the role of physical models in exploring form–process feedbacks in alluvial fans. Sediment Dynamics in Changing Environments. 1st - 5th Dec 2008.
Abstract:
An evaluation of the role of physical models in exploring form–process feedbacks in alluvial fans
Abstract.
Greenwood P, Walling DE, Quine TA (2008). Assessing the remobilisation of recently deposited sediment from river flood plains during single overbank flood events, using caesium-134 and cobalt-60 as tracers. Sediment Dynamics in Changing Environments. 1st - 5th Dec 2008.
Abstract:
Assessing the remobilisation of recently deposited sediment from river flood plains during single overbank flood events, using caesium-134 and cobalt-60 as tracers
Abstract.
Van Oost K, Six J, Govers G, Quine T, De Gryze S (2008). Response. Science, 319(5866).
Van OK, Six J, Govers G, Quine T, De GS (2008). Soil erosion: a carbon sink or source? Response. SCIENCE, 319(5866), 1042-1042.
2007
Thomas R, Nicholas AP, Quine TA (2007). Cellular modelling as a tool for interpreting historic braided river evolution.
Geomorphology,
90(3-4), 302-317.
Abstract:
Cellular modelling as a tool for interpreting historic braided river evolution
Results are presented from a new cellular model of braided river dynamics that simulates flow, sediment transport, morphological change and the effects of braidplain vegetation. This model is used to investigate the effect of changes in upstream sediment supply on braided river systems over simulation periods of 200 years. Modelled changes in channel morphology, associated with both aggradation and degradation, were seen to be consistent with those reported in the literature. In addition, simulation results allowed the identification of diagnostic characteristics of aggrading and degrading reaches, in the form of relationships between the age, extent and relative elevation of fluvial surfaces. Interpretation of spatial patterns of valley floor surface characteristics in the Avoca River, New Zealand, on the basis of these relationships, allowed the identification of channel reaches that appear to be experiencing either aggradation or degradation. These inferences are shown to be consistent with independent evidence of spatial patterns of sediment supply to the main valley floor, derived from aerial photographs and an existing sediment source inventory. These results illustrate the potential for using cellular models to develop an improved understanding of natural river behaviour. © 2007 Elsevier B.V. All rights reserved.
Abstract.
Nicholas AP, Quine TA (2007). Crossing the divide: Representation of channels and processes in reduced-complexity river models at reach and landscape scales. Geomorphology, 90(3-4), 318-339.
Nicholas AP, Quine TA (2007). Modelling alluvial landform change in the absence of external environmental forcing. Geology, 35(6), 527-530.
Quine TA, van Oost K (2007). Quantifying carbon sequestration as a result of soil erosion and deposition: retrospective assessment using caesium-137 and carbon inventories. Global Change Biology, 13, 2610-2625.
VanOost K, Quine TA, De Gryze S, Govers G (2007). The impact of agricultural soil erosion on the Global Carbon Cycle. Science, 318(5850), 626-629.
Navas A, Walling DE, Quine T, Machin J, Soto J, Domenech S, Lopez-Vicente M (2007). Variability in (CS)-C-137 inventories and potential climatic and lithological controls in the central Ebro valley, Spain.
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY,
274(2), 331-339.
Abstract:
Variability in (CS)-C-137 inventories and potential climatic and lithological controls in the central Ebro valley, Spain
The extent of soil erosion in some Spanish semiarid regions has caused great concern regarding the sustainability of soil resources. Accelerated soil erosion, particularly in some Mediterranean areas, is likely to be one of the main environmental problems associated with climate change. Fallout Cs-137 has been shown to provide a reliable basis for assessing soil erosion rates in different environments around the world. However, existing information concerning the spatial variation of Cs-137 inventories at reference sites has identified a need for further investigation of the factors affecting their spatial variability in semiarid environments, where stony and skeletal soils are predominant. Reference sites at three locations in the central Ebro valley were selected to investigate the Cs-137 content of several grain size fractions. Each site included both natural vegetated conditions and cultivated land and the three sites were characterized by different values of mean annual rainfall. The results obtained demonstrate the influence of lithology, land use and climate on the spatial variability of Cs-137 inventories that increase from 1190, to 1500 and 1710 Bq center dot m(-2) with increasing annual rainfall values from 300 to 500 mm at the study sites. The soils on marls at the Valare (n) over tildea site had the highest proportion of Cs-137 in the coarse fractions of cultivated soils (12%) in comparison with soils developed on limestones at Loma Negra (5%), whereas no Cs-137 content was found in the coarse fractions of soils on glacis-terrace materials at Pe (n) over tilde aflor. The Cs-137 reference inventories are higher in soils on marls and sands at cultivated locations at Valare (n) over tildea and Pe (n) over tilde aflor, but have similar values in soils at cultivated and uncultivated locations on limestones at Loma Negra. Therefore, in absence of level undisturbed soils with natural vegetation cover, cultivated flat soils on hard rocks could provide reliable reference inventories.
Abstract.
2006
Van Oost K, Quine TA, Govers G, Heckrath G (2006). Modeling soil erosion induced carbon fluxes between soil and atmosphere on agricultural land using SPEROS-C.
Author URL.
Quine TA, Zhang Y (2006). Re‐defining tillage erosion: quantifying intensity–direction relationships for complex terrain. Soil Use and Management, 20(2), 114-123.
Quine TA, Zhang Y (2006). Re‐defining tillage erosion: quantifying intensity–direction relationships for complex terrain. Soil Use and Management, 20(2), 124-132.
Zhang, J. Quine TA, Ni, S. Ge, F. (2006). Stocks and dynamics of SOC in relation to soil distribution by water and tillage erosion. Global Change Biology, 12(10), 1834-1841.
Van Oost K, Govers G, de Alba S, Quine TA (2006). Tillage erosion: a review of controlling factors and implications for soil quality.
Progress in Physical Geography,
30(4), 443-466.
Abstract:
Tillage erosion: a review of controlling factors and implications for soil quality
Tillage erosion has been identified as an important global soil degradation process that has to be accounted for when assessing the erosional impacts on soil productivity, environmental quality or landscape evolution. In this paper, we present a summary of available data describing tillage erosion. This provides insights in the controlling factors determining soil redistribution rates and patterns by tillage for various implements used in both mechanized and non-mechanized agriculture. Variations in tillage depth and tillage direction cause the largest variations in soil redistribution rates, although other factors, such as tillage speed and implement characteristics, also play an important role. In general, decreasing tillage depth and ploughing along the contour lines substantially reduce tillage erosion rates and can be considered as effective soil conservation strategies. Implement erosivities reported in literature, characterized by the tillage transport coefficient, are very consistent and range in the order of 400-800 kg m-1 yr-1 and 70-260 kg m-1 yr-1 for mechanized and non-mechanized agriculture, respectively. Comparison of tillage erosion rates with water erosion rates using a global data set indicates that tillage erosion rates are at least in the same order of magnitude or higher than water erosion rates, in almost all cases. Finally, we discuss how tillage erosion increases the spatial variability of soil properties and affects soil nutrient cycling. Considering the widespread use of tillage practices, the high redistribution rates associated with the process and its direct effect on soil properties, it is clear that tillage erosion should be considered in soil landscape studies. © 2006 SAGE Publications.
Abstract.
2005
Quine TA (2005). Book Review: Understanding and solving environmental problems in the 21st century: toward a new, integrated hard problem science. The Holocene, 15(1), 158-158.
Van Oost K, Van Muysen W, Govers G, Deckers J, Quine TA (2005). From water to tillage erosion dominated landform evolution.
Geomorphology,
72(1-4), 193-203.
Abstract:
From water to tillage erosion dominated landform evolution
While water and wind erosion are still considered to be the dominant soil erosion processes on agricultural land, there is growing recognition that tillage erosion plays an important role in the redistribution of soil on agricultural land. In this study, we examined soil redistribution rates and patterns for an agricultural field in the Belgian loess belt. 137Cs derived soil erosion rates have been confronted with historical patterns of soil erosion based on soil profile truncation. This allowed an assessment of historical and contemporary landform evolution on agricultural land and its interpretation in relation to the dominant geomorphic process. The results clearly show that an important shift in the relative contribution of tillage and water erosion to total soil redistribution on agricultural land has occurred during recent decades. Historical soil redistribution is dominated by high losses on steep midslope positions and concavities as a result of water erosion, leading to landscape incision and steepening of the topography. In contrast, contemporary soil redistribution is dominated by high losses on convex upperslopes and infilling of slope and valley concavities as a result of tillage, resulting in topographic flattening. This shift must be attributed to the increased mechanization of agriculture during recent decades. This study shows that the typical topographical dependency of soil redistribution processes and their spatial interactions must be accounted for when assessing landform and soil profile evolution. © 2005 Published by Elsevier B.V.
Abstract.
VanOost K, Govers G, Quine TA, Heckrath G, Oleson J, Merckx R (2005). Landscape-scale modeling of carbon cycling under the impact of soil redistribution: the role of tillage erosion. Global Biogeochemical Cycles, 19(4).
Navas A, Walling DE, Quine TA, Machin J, Soto J (2005). The pattern of soil redistribution along a transect in the central Ebro basin (NE Spain) and its controls.
Abstract:
The pattern of soil redistribution along a transect in the central Ebro basin (NE Spain) and its controls
Abstract.
Heckrath G, Djurhuus J, Quine TA, Van Oost K, Govers G, Zhang Y (2005). Tillage erosion and its effect on soil properties and crop yield in Denmark.
J Environ Qual,
34(1), 312-324.
Abstract:
Tillage erosion and its effect on soil properties and crop yield in Denmark.
Tillage erosion had been identified as a major process of soil redistribution on sloping arable land. The objectives of our study were to investigate the extent of tillage erosion and its effect on soil quality and productivity under Danish conditions. Soil samples were collected to a 0.45-m depth on a regular grid from a 1.9-ha site and analyzed for 137Cs inventories, as a measure of soil redistribution, soil texture, soil organic carbon (SOC) contents, and phosphorus (P) contents. Grain yield was determined at the same sampling points. Substantial soil redistribution had occurred during the past decades, mainly due to tillage. Average tillage erosion rates of 2.7 kg m(-2) yr(-1) occurred on the shoulderslopes, while deposition amounted to 1.2 kg m(-2) yr(-1) on foot- and toeslopes. The pattern of soil redistribution could not be explained by water erosion. Soil organic carbon and P contents in soil profiles increased from the shoulder- toward the toeslopes. Tillage translocation rates were strongly correlated with SOC contents, A-horizon depth, and P contents. Thus, tillage erosion had led to truncated soils on shoulderslopes and deep, colluvial soils on the foot- and toeslopes, substantially affecting within-field variability of soil properties. We concluded that tillage erosion has important implications for SOC dynamics on hummocky land and increases the risk for nutrient losses by overland flow and leaching. Despite the occurrence of deep soils across the study area, evidence suggested that crop productivity was affected by tillage-induced soil redistribution. However, tillage erosion effects on crop yield were confounded by topography-yield relationships.
Abstract.
Author URL.
2004
VanOost, K. Govers, G. Heckrath, G. (2004). Comment on Managing Soil Carbon. Science, 305(5690).
Quine TA, Zhang Y (2004). Re-defining tillage erosion: Quantifying intensity-direction relationships for complex terrain. 2. Revised mouldboard erosion model.
Soil Use and Management,
20(2), 124-132.
Abstract:
Re-defining tillage erosion: Quantifying intensity-direction relationships for complex terrain. 2. Revised mouldboard erosion model
Current tillage erosion models account for the influence of tillage direction in the magnitude of the soil transport coefficient. It is argued that a re-modelling of tillage erosion is preferable in which the influence of tillage direction is separated from the soil transport coefficient, which is a measure of tillage intensity. This has been achieved here by developing a two-dimensional tillage erosion model that incorporates tillage direction in the measure of slope and uses soil transport coefficients that are independent of tillage direction and based on relationships between transport and the slope in the direction that bisects tillage direction and the overturning direction. Mean tillage erosion, associated with a single pair of opposing tillage directions and pair of overturning directions, can be described by a two-dimensional diffusion-type equation if the dimensions are defined as the tillage direction and the direction perpendicular to tillage. Application of the model to a real-world case allows quantification of the potential soil conservation benefits associated with optimization of tillage direction. The scope for amelioration is related to the ratio between the coefficients for transport in the direction of tillage and perpendicular to tillage. As this ratio approaches unity, the potential for amelioration reduces towards zero. For the study site investigated, use of the experimentally derived ratio of 0.66 indicated that a 12% reduction in tillage erosion could be obtained by ploughing across the dominant field slope as compared to ploughing up and down the dominant slope. For an implement with a coefficient ratio of 0.2 the reduction in tillage erosion intensity, associated with optimizing the tillage direction, reaches 28%. Nevertheless, such benefits must be considered in the context of other management considerations. The tillage direction that minimizes erosion is associated with lateral slopes of 10°, or more, over 20% of the field. To the land-user this disadvantage may outweigh the soil conservation benefits.
Abstract.
Quine TA, Zhang Y (2004). Re-defining tillage erosion: quantifying intensity - direction relationships for complex terrain. (1) Derivation of an adirectional soil transport coefficient. Soil Use and Management, 20(2), 114-123.
2003
Van Oost K, Van Muysen W, Govers G, Heckrath G, Quine TA, Poesen J (2003). Simulation of the redistribution of soil by tillage on complex topographies.
European Journal of Soil Science,
54(1), 63-76.
Abstract:
Simulation of the redistribution of soil by tillage on complex topographies
Tillage redistributes soil and contributes significantly to the within-field soil variation, especially on topographically complex terrain. Although the basic principles of the redistribution are well understood, models for simulating the redistribution are poor predictors. This paper presents a modelling structure that allows a simulation of the redistribution of soil constituents on complex topographies for various tillage implements. The model simulates the redistribution of soil constituents by convoluting the probability distribution of the tillage displacement with the spatial distribution of the soil constituents. The probability distributions in two dimensions are derived from a series of tillage experiments conducted with a mouldboard plough at various positions in the landscape. Furthermore, the effects of topography and tillage direction on the probability distributions were characterized and implemented in the model. A first application showed that the direction of tillage significantly affects the long-term redistribution of soil constituents. The inclusion of other implements in the model was explored, and we found that data in the literature could be used for simulating the long-term effects of tillage.
Abstract.
Quine TA, Basher LR, Nicholas AP (2003). Tillage erosion intensity in the South Canterbury Downlands, New Zealand.
Australian Journal of Soil Research,
41(4), 789-807.
Abstract:
Tillage erosion intensity in the South Canterbury Downlands, New Zealand
Growing awareness of the pressure on land resources emphasises the need to understand the full range of processes operating in human-impacted agroecosystems. In such systems one of the greatest threats to long-term sustainability is the erosion and depauperation of soil, which, until recently, was attributed almost entirely to water erosion. This study builds on recent awareness of the significance of tillage erosion and presents the results of an experimental investigation of tillage erosion due to mouldboard ploughing. Aluminium cubes were used to trace soil translocation as a result of a single pass of the plough perpendicular to the contour in downslope and upslope directions. In common with others studies, translocation was found to be directly proportional to slope tangent for downslope tillage and unrelated to slope for upslope tillage. The influence of non-topographic variables on the relationship between translocation distance and slope was partially filtered out by using the ratio of translocation distances in the tillage direction and perpendicular to tillage. Shallow plough depths of 0.17 m produced tillage detachment of only 230 kg/m2; however, a high tillage translocation coefficient of 1.16 m/pass resulted in a soil flux coefficient of 265 kg/m.pass. The high tillage translocation coefficient is probably partly due to the loose nature of the regularly cultivated loessic soil, however, on the basis of comparison with other published studies, it is suggested that the high tillage speed of 7 km/h is the principal control on the magnitude of the coefficient. Analysis of the available data suggests that a 30% reduction in tillage erosion intensity could be obtained by reduction of the tillage speed to 4 km/h; nevertheless, more experimental work is needed to test this suggestion. On the transect studied, a pair of opposing passes of the mouldboard plough would produce erosion rates as high as 5.1 kg/m2.year (51 t/ha.year) from shoulder slope elements and as high as 1.9 kg/m2.year (19 t/ha.year) over half of the slope length. This pattern matched closely the distribution of 137Cs-derived erosion rates documented previously for a nearby field, suggesting that for this environment, as for many mechanised agricultural systems, tillage erosion is the dominant soil redistribution process and the greatest threat to long-term sustained on-site productivity. Reduction of tillage erosion should, therefore, be seen as a priority in the development of sustainable land management strategies.
Abstract.
2002
Quine TA, Zhang Y (2002). An investigation of spatial variation in soil erosion, soil properties and crop production within an agricultural field in Devon, United Kingdom. Journal of Soil and Water Conservation, 57(1), 55-65.
2001
Lobb DA, Quine TA, Govers G, Heckrath GJ (2001). Comparison of methods used to calculate tillage translocation using plot-tracers.
Journal of Soil and Water Conservation,
56(4), 321-328.
Abstract:
Comparison of methods used to calculate tillage translocation using plot-tracers
Tillage translocation is measured in the studies of soil dispersion and soil erosion. The translocation of soil by tillage is normally measured with a tracer. Using plots, a volume of soil is labelled and then tilled. There are two methods of calculating translocation using plot-tracers. For the more common method, translocation is calculated directly from the distributions of tracer before and after tillage (Distribution-Curve Method). For the less common method, a summation curve is generated from the distribution of tracer after tillage by employing convolution, and translocation is calculated from this curve (Summation-Curve Method). In this paper, the two methods are described and compared using hypothetical and experimental data. Both methods provide accurate measures of gross translocation. The Summation-Curve Method provides a measure of error associated with gross translocation and a more thorough characterization of the dispersion of translocated soil; therefore, it was considered to be the superior of the two methods.
Abstract.
Kosmas C, Gerontidis S, Marathianou M, Detsis B, Zafiriou T, Nan Muysen W, Govers G, Quine T, Vanoost K (2001). The effects of tillage displaced soil on soil properties and wheat biomass.
Soil and Tillage Research,
58(1-2), 31-44.
Abstract:
The effects of tillage displaced soil on soil properties and wheat biomass
Tillage operations transport large amounts of soil from convex slopes and deposit on concavities in hilly cultivated areas. Field experiment was conducted to assess tillage induced soil displacement and its effects on soil properties and wheat (Triticum aestivum L.) biomass production. The study was done on 3.5 ha fertilized and wheat seeded hillslope (14-21% slope) located 100 km north of Athens, Greece. Numbered aluminum cylinders (700), each 10 mm diameter by 10 mm height, were buried in soil as soil movement tracers (SMTs) to estimate soil displacement as a function of moldboard plowing with two depths in up-slope and down-slope directions. Furthermore, clay, organic matter, rock fragment content, phosphorus and 137Cs were determined on 81 soil bulk cores to estimate soil redistribution rates along the study hillslope. Soil depth and soil water storage were measured in 81 soil sites and related to the wheat biomass production. The mean SMT displacement distance due to 25-cm plow depth on 21% slope was 42 cm for down-slope tillage and 16 cm for up-slope tillage. Comparable values were 31 cm for down-slope and 14 cm for up-slope tillage on 14% slope gradient. The SMT distance for both tillage directions on 21% slope was about 60% less for 18-cm plow depth compared with 25-cm plow depth. Shallow soil (depth 70 cm) was found on lower concavities where displaced soil was deposited. The spatial pattern or 137Cs inventories suggests that tillage erosion is a major erosion process in the study area. The maximum leaf area index of wheat was 2.8 for convex slope and 3.6 for concave slope. Wheat biomass, ranging from 0.2 to 1.2 kg m-2, increased logarithmically with increased soil depth. Moldboard plowing displaced large amounts of soil from convex slope which changed soil properties to less favorable for wheat production. Application of the obtained empirical functions showed that under the existing climatic conditions and management practices, the unprofitably productive area will increase from 4.1 to 6.8% in a period of 7 years. © 2001 Elsevier Science B.V.
Abstract.
2000
Zhang XB, Quine TA (2000). A study of soil erosion on a steep cultivated slope in the Mt. Gongga region near Luding, Sichuan, China, using the <sup>137</sup>Cs technique.
Acta Geologica Hispanica,
35(3-4), 229-238.
Abstract:
A study of soil erosion on a steep cultivated slope in the Mt. Gongga region near Luding, Sichuan, China, using the 137Cs technique
This paper reports the results of an investigation of soil erosion on a steep cultivated slope in the Mt Gongga region of the Upper Yangtze River Basin, Southwest China, using the 137Cs technique. The effective 137Cs reference inventory for the study field, estimated from the bottom layer of a 137Cs depth profile at the deposition zones, is 2373.9 Bq/m2, accounting for 65.8% the local 137Cs reference inventory of 3607.7 Bq/m2. It strongly indicates that a considerable amount of 137Cs input was lost prior to incorporation into the ploughing layer from the study field during the nuclear weapons testing period because of 137Cs surface enrichment. The average erosion rate is estimated to be 4914 t/km2yr for a typical cultivated steep slope with an angle of 34° at the subtropical zone in the Mt Gongga region. It can reach to 22856 t/km2yr for a failure slope under cultivation.
Abstract.
Van Oost K, Govers G, Van Muysen W, Quine TA (2000). Modeling translocation and dispersion of soil constituents by tillage on sloping land.
Soil Science Society of America Journal,
64(5), 1733-1739.
Abstract:
Modeling translocation and dispersion of soil constituents by tillage on sloping land
Recent studies clearly indicated that soil tillage is a major factor affecting soil redistribution on arable land. However, existing modeling studies of the redistribution of soil constituents by tillage are largely theoretical in nature due to the lack of sufficient experimental data. This paper describes the results of field experiments carried out with a moldboard plow on different slope gradients showing that an important net downslope translocation and dispersion of soil constituents is associated with soil tillage. Both translocation and dispersion are strongly affected by slope gradient. Available experimental evidence suggests that redistribution of soil constituents can be modeled by convoluting the displacement probability distribution with the spatial distribution of the soil constituent. The convolution model presented here was found to be superior to existing models because it accounts for dispersion, directionality of tillage, and topography. A comparison of soil property data with model simulations indicated that soil tillage is a major factor when assessing the effect of erosion processes on the variability of soil properties.
Abstract.
Steegen A, Govers G, Beuselinck L, Van Oost K, Quine TA, Rombaut A (2000). The use of phosphorus as a tracer in erosion/sedimentation studies.
Abstract:
The use of phosphorus as a tracer in erosion/sedimentation studies
Abstract.
1999
Quine TA, Govers G, Poesen J, Walling D, Van Wesemael B, Martinez-Fernandez J (1999). Fine-earth translocation by tillage in stony soils in the Guadalentin, south-east Spain: an investigation using caesium-134.
Soil and Tillage Research,
51(3-4), 279-301.
Abstract:
Fine-earth translocation by tillage in stony soils in the Guadalentin, south-east Spain: an investigation using caesium-134
Tillage erosion is increasingly recognised as an important soil erosion process on agricultural land. In view of its potential significance, there is a clear need to broaden the experimental database for the magnitude of tillage erosion to include a range of tillage implements and agricultural environments. The study discussed in this paper sought to address the need for such data by examining tillage erosion by a duckfoot chisel plough in stony soils on steep slopes in a semi-arid environment. Results of the investigation of coarse fraction (rock fragment) translocation by tillage in this environment have been presented elsewhere and the paper focuses on tillage translocation and erosion of the fine earth. Tillage translocation was measured at 10 sites, representing both upslope and downslope tillage by a duckfoot chisel plough on five different slopes, with tangents ranging from 0.02 to 0.41. A fine-earth tracer, comprising fine earth labelled with 134Cs, was introduced into the plough layer before tillage. After a single pass of the plough, incremental samples of plough soil were excavated and sieved to separate the fine earth from the rock fragments. Translocation of the fine-earth tracer was established by analysing the 134Cs content of the samples of fine earth. These data were used to establish translocation distances for each combination of slope and tillage direction. Translocation distances of the fine earth were not significantly different from translocation distances of the coarse fraction. For all sites, except uphill on the 0.41 slope, translocation distances were found to be linearly related to slope tangent. The soil flux due to tillage for each site was calculated using the translocation distance and the mass per unit area of the plough layer. For slopes with tangents
Abstract.
Brown AG, Quine TA (1999). Fluvial processes and environmental change: an overview.
Author URL.
Govers G, Lobb DA, Quine TA (1999). Preface - Tillage erosion and translocation: emergence of a new paradigm in soil erosion research.
SOIL & TILLAGE RESEARCH,
51(3-4), 167-174.
Author URL.
Quine TA, Walling DE, Chakela QK, Mandiringana OT, Zhang X (1999). Rates and patterns of tillage and water erosion on terraces and contour strips: Evidence from caesium-137 measurements.
Catena,
36(1-2), 115-142.
Abstract:
Rates and patterns of tillage and water erosion on terraces and contour strips: Evidence from caesium-137 measurements
Despite the widespread use of contour-strips and terraces for soil conservation little is known concerning the impact of such measures on rates and patterns of tillage erosion and tillage translocation. Caesium-137 (137Cs) measurements would appear to offer a rapid means of assembling data relevant to the evaluation of tillage erosion and tillage translocation. However, use of 137Cs data in this way requires an approach to the analysis of 137Cs data which accounts for both tillage erosion and tillage translocation. The latter is particularly significant on short slopes. A method of analysing 137Cs data has been developed, that employs a linear, multistore, mass-balance model of soil and 137Cs redistribution to permit estimation of the contributions to erosion from both water and tillage erosion. This method is outlined and results from its application are discussed using case studies from Yanting, in Sichuan Province, China; Ha Sofonia, in Lesotho; and, Chinamora, in Zimbabwe. These case studies confirm the viability of the approach and provide valuable evidence for the importance of tillage erosion and translocation on terraces and contour-strips subject to cultivation by animal traction. Gross rates of tillage erosion were found to be of comparable or greater magnitude than gross rates of water erosion on the fields examined. It is, therefore, suggested that any evaluation of on-site impacts of erosion must take account of tillage erosion. Relationships between annual soil fluxes due to tillage and slope tangent were found to be very similar to the relationships established for a single pass of equivalent tillage equipment with mechanical traction. Furthermore, because tillage by animal traction necessitates downslope turning of the soil on every occasion, net downslope fluxes of soil associated with animal traction may exceed the levels associated with tillage by mechanised traction, in which the soil is typically turned in opposing directions on successive occasions.
Abstract.
Beuselinck L, Govers G, Steegen A, Quine TA (1999). Sediment transport by overland flow over an area of net deposition.
Hydrological Processes,
13(17), 2769-2782.
Abstract:
Sediment transport by overland flow over an area of net deposition
Flume studies were conducted in order to evaluate the influence of slope, sediment size, discharge and inflow sediment concentration on sediment deposition by overland flow. Additionally, experiments were carried out to measure transport capacity of overland flow at low slopes, using a wide range of discharges. The experimental data show that the hydraulic conditions where net deposition occurs can be divided into two domains. The first domain is characterized by hydraulic conditions where transport capacity is not significant. In the second domain net deposition still occurs but transport capacity is significant. The size of the latter domain is dependent on the sediment size distribution, on the hydraulic roughness and on the inflow sediment concentration. The experiments clearly indicate the necessity of incorporating a threshold value in any deposition equation. These experiments demonstrate that shear stress is a valuable threshold for deposition modelling.
Abstract.
Quine TA, Walling D, Zhang XB (1999). Slope and gully response to agricultural activity in the rolling Loess Plateau, China.
Author URL.
Govers G, Lobb DA, Quine TA (1999). Tillage erosion and translocation: Emergence of a new paradigm in soil erosion research. Preface. Soil and Tillage Research, 51(3-4), 167-174.
Quine TA, Walling DE, Zhang X (1999). Tillage erosion, water erosion and soil quality on cultivated terraces near Xifeng in the Loess Plateau, China.
Land Degradation and Development,
10(3), 251-274.
Abstract:
Tillage erosion, water erosion and soil quality on cultivated terraces near Xifeng in the Loess Plateau, China
This study sought to contribute to the understanding of soil redistribution by tillage on terraces and the extent and causes of within-field variation in soil properties by examining the spatial distributions of soil redistribution rates, derived using caesium-137, and of total nitrogen and total phosphorus concentrations, within a ribbon and a shoulder terrace in a yuan area of the Loess Plateau of China. Additional water erosion rate data were obtained for nine other terraces. Water erosion rates on the ribbon terraces were low (
Abstract.
Quine TA (1999). Use of caesium-137 data for validation of spatially distributed erosion models: the implications of tillage erosion.
Catena,
37(3-4), 415-430.
Abstract:
Use of caesium-137 data for validation of spatially distributed erosion models: the implications of tillage erosion
Validation of spatially distributed models using spatially distributed data represents a vital element in the development process; however, it is rarely undertaken. To a large extent, this reflects the problems associated with assembling erosion rate data, at appropriate temporal and spatial scales and with a suitable spatial resolution, for comparison with model results. The caesium-137 (137Cs) technique would appear to offer considerable potential for meeting this need for data, at least for longer timescales. Nevertheless, initial attempts to use 137Cs for model validation did not prove successful. This lack of success may be explained by the important role of tillage erosion in redistributing soil within agricultural fields and, therefore, contributing to the 137Cs-derived soil redistribution rates. This paper examines the implications of tillage erosion for the use of 137Cs in erosion model validation and presents an outline methodology for the use of 137Cs in model validation. This methodology acknowledges and addresses the constraints imposed by the need to: (1) separate water and tillage erosion contributions to total soil redistribution as represented in 137Cs derived rates; (2) account for lateral mixing of 1367Cs within fields as a result of tillage translocation; (3) simulate long-term water erosion rates using the model under evaluation if 137Cs-derived water erosion rates are to be used in model validation. The methodology is dependent on accurate simulation of tillage erosion and tillage translocation. Therefore, as greater understanding of tillage erosion is obtained, the potential for the use of 137Cs in water erosion model validation will increase. Caesium-137 measurements remain one of the few sources of spatially distributed erosion information and, therefore, their potential value should be exploited to the full.
Abstract.
1998
King BP, Quine TA, Walling DE, SEDIMENTAT INTRESTCTRE, SEDIMENTAT INTRESTCTRE (1998). Assessment of within-field sediment storage in agricultural catchments using a terrain-based GIS.
Author URL.
Zhang X, Quine TA, Walling DE (1998). Soil erosion rates on sloping cultivated land on the Loess Plateau near Ansai, Shaanxi Province, China: an investigation using <sup>137</sup>Cs and rill measurements.
Hydrological Processes,
12(1), 171-189.
Abstract:
Soil erosion rates on sloping cultivated land on the Loess Plateau near Ansai, Shaanxi Province, China: an investigation using 137Cs and rill measurements
Sediment yields from the rolling hills area of the Loess Plateau in northern China (10 000-25 000 t km-2 yr-1) are amongst the highest in the world. The sediment is believed to derive from both the deep gullies that dissect the rolling plateau and the steep cultivated fields on the slopes of the mounds between the gullies. However, there are few reliable data for erosion rates on the cultivated fields and it is suspected that current estimates (10 000-16 000 t km-2 yr-1) based on empirical relationships (derived from erosion plot studies) exceed the true values. This study sought to address the need for more information concerning erosion of the cultivated fields through derivation of erosion rates from measurements of rill volume and caesium-137 (137Cs) inventories for typical fields near the village of Ansai, Shaanxi Province. The derived erosion rates are discussed and compared with estimates based on empirical relationships derived from erosion plot data. Where erosion rate estimates based on both rill volume data and 137Cs inventories are available, they show good agreement in the pattern of downslope variation. Both show a sharp decline in erosion rates at a slope length of c. 50 m. This is tentatively attributed to a change from transport-limited to detachment-limited conditions, where rill incision reaches the undisturbed loess at the base of the plough layer. No such decline is visible in the predictions based on empirical relationships derived from erosion plot data. Further evidence is presented that supports the suggestion that these empirical relationships overestimate erosion rates at slope lengths in excess of c. 50 m. It is tentatively suggested that the rates of soil erosion from sloping cultivated fields in the rolling hills area are more likely to lie in the range 8000-10000 t km-2 yr-1 than in the higher range suggested by the empirical relationships. © 1998 John Wiley Sons, Ltd.
Abstract.
1997
Wagner A, Greenland DJ, Lal R, Quine T, Billing DW, Evans R, Giller K (1997). Degradation and resilience of soils - Discussion.
PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY OF LONDON SERIES B-BIOLOGICAL SCIENCES,
352(1356), 1008-1010.
Author URL.
Quine TA, Govers G, Walling DE, Zhang X, Desmet PJJ, Zhang Y, Vandaele K (1997). Erosion processes and landform evolution on agricultural land - New perspectives from caesium-137 measurements and topographic-based erosion modelling.
Earth Surface Processes and Landforms,
22(9), 799-816.
Abstract:
Erosion processes and landform evolution on agricultural land - New perspectives from caesium-137 measurements and topographic-based erosion modelling
Despite growing interest in soil erosion on agricultural land, relatively little attention has been paid to the influence of erosion processes on the pattern of contemporary landform evolution. This in part reflects the problems associated with up-scaling the results of short-term process studies to temporal and spatial scales relevant to the study of landform evolution. This paper presents a new approach to examining the influence of erosion processes on landform evolution on agricultural land which employs: caesium-137 (137Cs) measurements to provide medium-term (c.40 years) estimates of rates of landform change; experimental data and a topographic-based model to simulate soil redistribution by tillage; a mass-balance model of 137Cs redistribution to separate the water erosion and tillage components of the 137Cs 'signatures'; and field observations of water erosion for validation. This approach is used to examine the relative importance of water erosion and tillage processes for contemporary landform evolution at contrasting sites near Leuven, in Belgium, and near Yanan, in Shaanxi Province, China. This application of the approach provides good agreement between the derived water erosion rates and field observations, and hitherto unobtainable insights into medium-term patterns and rates of contemporary landform evolution. At Huldenberg in Belgium, despite rill incision of slope concavities and ephemeral gully incision of the valley floor, contemporary landform evolution is dominated by infilling of slope and valley concavities (rates >0·5 mm a-1) and gradual lowering of slope angles as a result of tillage. In contrast, at Ansai (near Yanan) the slope is characterized by increase in slope angle over most of the length, recession of the steepest section at a rate >5mm a-1 and by increasing planform curvature. At this site, contemporary landform evolution is dominated by water erosion. The constraints on the approach are examined, with particular attention being given to limitations on extrapolation of the results and to the sensitivity of the models to parameter variation. © 1997 by John Wiley & Sons, Ltd.
Abstract.
Poesen J, Van Wesemael B, Govers G, Martinez-Fernandez J, Desmet P, Vandaele K, Quine T, Degraer G (1997). Patterns of rock fragment cover generated by tillage erosion.
Geomorphology,
18(3-4), 183-197.
Abstract:
Patterns of rock fragment cover generated by tillage erosion
Intensively cultivated areas in the upper part of the Guadalentin catchment (southeast Spain) show a systematic spatial pattern of surface rock fragment cover (Rc). The objective of this paper is to quantify and to explain this spatial rock fragment cover pattern. Therefore, a map of an intensively cultivated area of 5 km2 was digitised, and for each pixel total topographic curvature was calculated. Next, rock fragment cover was determined photographically at 35 sites with a range of total slope curvatures. A linear relation between total curvature and rock fragment cover was found, except for narrow concavities. It was hypothesised that this pattern can be explained by a significant net downslope movement of rock fragments and fine earth by tillage. The displacement distances of rock fragments by tillage with a duckfoot chisel were measured by monitoring the displacement of tracers (painted rock fragments and aluminium cubes) on 5 sites having different slopes. The rate of tillage erosion for one tillage pass with a duckfoot chisel, expressed by the diffusion constant (k), equals 282 kg/m for up and downslope tillage and only 139 kg/m for contour tillage. Nomograms indicate that mean denudation rates in almond groves due to tillage erosion (3 to 5 tillage passes per year) can easily amount to 1.5-2.6 mm/year for contour tillage and up to 3.6-5.9 mm/year for up- and downslope tillage for a field, 50 m long and having a slope of 20%. These figures are at least one order of magnitude larger than reported denudation rates caused by water erosion in similar environments. Hence tillage erosion contributes significantly to land degradation. The downslope soil flux induced by tillage not only causes considerable denudation on topographic convexities (hill tops and spurs) and upper field boundaries but also an important sediment accumulation in topographic concavities (hollows and valley bottoms) and at lower field boundaries. Kinetic sieving (i.e. the upward migration of rock fragments) by the tines of the duckfoot chisel also concentrates the largest rock fragments in the topsoil in such a way that a rock fragment mulch develops in narrow valleys and at the foot of the slopes. These results clearly indicate that tillage erosion is the main process responsible for the observed rock fragment cover pattern in the study area. Since the study area is representative for many parts of southern Spain where almond groves have expanded since 1970, the results have a wider application. They show to what extent intensive tillage of steep slopes has contributed to the increase in soil degradation, to changes in hillslope morphology (i.e. strong denudation of convexities, development of lynchets and rapid infilling of narrow valley bottoms) and to the development of rock fragment cover patterns which control the spatial variability of the hydrological and water erosion response within such landscapes.
Abstract.
Navas A, GarciaRuiz JM, Machin J, Lasanta T, Valero B, Walling DE, Quine TA (1997). Soil erosion on dry farming land in two changing environments of the central Ebro Valley, Spain.
Author URL.
Zhang X, Walling DE, Quine TA, Wen A (1997). Use of reservoir deposits and caesium-137 measurements to investigate the erosional response of a small drainage basin in the rolling loess plateau region of China.
Land Degradation and Development,
8(1), 1-16.
Abstract:
Use of reservoir deposits and caesium-137 measurements to investigate the erosional response of a small drainage basin in the rolling loess plateau region of China
This paper reports the results of an investigation of the erosional response of the 3.86 km2 Zhaojia Gully catchment in the rolling loess plateau region of Zichan County, Shaanxi Province, China. In the absence of direct measurements, information derived from reservoir deposits and from caesium-137 measurements on both the catchment soils and reservoir deposits was used to obtain a retrospective assessment of the longer-term (ca. 30 year) erosional response of the catchment and of the relative contributions of the rolling plateau surface and the gully areas to the sediment output from the basin. Net erosion rates on cultivated land occupying the gentle crest slopes and steeper lower slopes of the rolling plateau and the steep gully slopes were estimated to be 4500 t km-2 year-1, 8584 t km-2 year-1 and 15 851 t km-2 year-1, respectively. Estimates of annual sediment yield from the study catchment based on analysis of sediment deposits in the two sediment-trap reservoirs ranged between 4627 and 32 472 t km-2 year-1. Almost all the sediment transported from the catchment was contributed by 2-4 large floods each year. Measurements of the caesium-137 content of recent sediment deposits in a sediment-trap reservoir allowed the relative contributions of the total sediment yield derived from the rolling plateau and gully areas of the catchment to be estimated at 23 and 77 per cent, respectively. Analysis of the sediment deposits dating from 1973-1977 in another sediment trap reservoir allowed individual flood event couplets to be identified and indicated that the sediment associated with the first one or two floods in a season, when the soils of the plateau area were relatively dry, was derived primarily from the gully areas. The cultivated soils of the rolling plateau contributed an increased proportion of the total sediment yield during the latter stages of the flood season when the soils were wetter, and surface runoff and erosion were more widespread. Based on analysis of the caesium-137 content of the sediment deposited in this sediment-trap reservoir, the relative contributions of sediment from the rolling plateau and gully areas over the period 1973-1977 were estimated to be 21 and 79 per cent, respectively. The results obtained demonstrate the potential for using caesium-137 measurements and analysis of reservoir deposits to document the erosional response of a drainage basin. © 1997 by John Wiley & Sons, Ltd.
Abstract.
1996
Govers G, Quine TA, Desmet PJJ, Walling DE (1996). The relative contribution of soil tillage and overland flow erosion to soil redistribution on agricultural land.
EARTH SURFACE PROCESSES AND LANDFORMS,
21(10), 929-946.
Author URL.
Walling DE, He Q, Quine TA (1996). Use of fallout radionuclide measurements in sediment budget investigations.
Geomorphologie. Relief, Processus, Environnement,
3, 17-27.
Abstract:
Use of fallout radionuclide measurements in sediment budget investigations
The sediment budget concept has been widely accepted as a valuable tool for documenting and interpreting the contemporary processes of erosion and deposition operating within a drainage basin. However, it is often difficult to assemble the information which is required to establish a reliable sediment budget. Fallout radionuclides offer the geomorphologist considerable potential for this purpose, by affording a means of assembling retrospective information on average medium-term (ie 35-150 years) rates of erosion and deposition within the landscape on the basis of present-day sample collection. Examples of the application of both fallout radionuclides in the investigation of soil redistribution on slopes and floodplain sedimentation rates are presented.
Abstract.
Walling DE, He Q, Quine TA (1996). Use of fallout radionuclide measurements in sediment budget investigations/La mesure des retombées de radionucléides : un outil pour l'évaluation des bilans sédimentaires. Géomorphologie relief processus environnement, 2(3), 17-27.
1995
Quine TA (1995). Traces in hydrology edited by N.E. Peters, E. Hoehn, Ch. Leibundgut, N. Tase and D.E. Walling, International Association of Hydrological Sciences, Publication No. 215, IAHS Press, Wallingford, 1993. No. of pages: x + 350. Price: $60.00. ISBN 0‐947571‐68‐X. Earth Surface Processes and Landforms, 20(6), 579-579.
Walling DE, He Q, Quine TA (1995). Use of caesium-137 and lead-210 as tracers in soil erosion investigations.
Tracer technologies for hydrological systems. Proc. international symposium, Colorado, 1995, 163-172.
Abstract:
Use of caesium-137 and lead-210 as tracers in soil erosion investigations
There are two important limitations to the general application of the approach. These involve the complications introduced by inputs of Chernobyl-derived radiocaesium in many areas of Europe and the relatively low caesium-137 inventories encountered in some parts of the globe where fallout rates were low. Unsupported lead-210, a natural fallout radionuclide, can offer a viable alternative to caesium-137 as a sediment tracer in many environments. In addition, when used in combination with caesium-137, it offers potential as a complementary tracer, which can provide additional information on the erosional history of a site. The results of a study of soil redistribution within a small cultivated field at Butsford Barton, Colebrooke, Devon, UK are presented. -from Authors
Abstract.
Walling DE, He Q, Quine TA (1995). Use of caesium-137 and lead-210 as tracers in soil erosion investigations.
Abstract:
Use of caesium-137 and lead-210 as tracers in soil erosion investigations
Abstract.
WALLING DE, QUINE TA, AGCY INTAE (1995). Use of fallout radionuclide measurements in soil erosion investigations.
Author URL.
1994
Quine TA, Desmet PJJ, Govers G, Vandaele K, Walling DE (1994). A comparison of the roles of tillage and water erosion in landform development and sediment export on agricultural land near Leuven, Belgium.
Abstract:
A comparison of the roles of tillage and water erosion in landform development and sediment export on agricultural land near Leuven, Belgium
Abstract.
ZHANG XB, QUINE TA, WALLING DE, LI Z (1994). APPLICATION OF THE CESIUM-137 TECHNIQUE IN a STUDY OF SOIL-EROSION ON GULLY SLOPES IN a YUAN AREA OF THE LOESS PLATEAU NEAR XIFENG, GANSU PROVINCE, CHINA.
GEOGRAFISKA ANNALER SERIES A-PHYSICAL GEOGRAPHY,
76(1-2), 103-120.
Author URL.
Zhang X, Quine TA, Walling DE, Li Z (1994). Application of the Caesium-137 Technique in a Study of Soil Erosion on Gully Slopes in a Yuan Area of the Loess Plateau Near Xifeng, Gansu Province, China. Geografiska Annaler: Series A, Physical Geography, 76(1-2), 103-120.
Xinbao Zhang, Quine TA, Walling DE, Zhou Li (1994). Application of the caesium-137 technique in a study of soil erosion on gully slopes in a yuan area of the Loess Plateau near Xifeng, Gansu Province, China.
Geografiska Annaler, Series A,
76 A(1-2), 103-120.
Abstract:
Application of the caesium-137 technique in a study of soil erosion on gully slopes in a yuan area of the Loess Plateau near Xifeng, Gansu Province, China
The patterns shown by caesium-137 inventories were used to interpret the dominant erosion processes operating on cultivated and uncultivated land. These patterns demonstrate the importance of tillage redistribution and water erosion on cultivated terraces and suggest that both wind and water erosion processes operate on grassland areas. Rates of erosion previously derived for the sites on uncultivated land may be a serious underestimate, although the data do confirm the importance of full vegetation cover in controlling erosion. The erosion rates derived for terraced cultivated sites are in line with published estimates. Two terrace types were characterized by widely divergent net erosion rated indicating that narrow-strip terraces cultivated parallel to the contour should be used where possible, because these offer a clear soil conservation benefit. -from Authors
Abstract.
Quine TA, Navas A, Walling DE, Machin J (1994). Soil erosion and redistribution on cultivated and uncultivated land near las bardenas in the central Ebro river Basin, Spain.
Land Degradation & Development,
5(1), 41-55.
Abstract:
Soil erosion and redistribution on cultivated and uncultivated land near las bardenas in the central Ebro river Basin, Spain
The semiarid regions of Spain, including the central part of the Ebro River basin, are under threat due to desertification. Severe erosion, as a result of poor land management, has led to degradation of the soil resource, and there is a clear need for quantitative erosion rate data to evaluate the problem. This study aimed to examine the potential for using caesium‐137 to identify the patterns and rates of soil erosion and redistribution within this semiarid environment. Samples for the determination of caesium‐137 were collected from uncultivated slopes and cultivated valley floor sites near the head and outlet of a small representative basin in the Las Bardenas area. The measured patterns of caesium‐137 mobilization, redistribution and export provide a semiquantitative indication of the variation in erosion within the study site. Calibration of the caesium‐137 measurements, taking account of the differing behaviour of radiocaesium on cultivated and uncultivated land, allows estimation of the actual rates of erosion and deposition involved. The results show (1) the erosion rates on the cultivated land (1.6–2.5 kg m−2 yr−1) are typically more than five times those seen on the uncultivated land (0.2–0.4 kg m−2 yr−1), and (2) erosion on the uncultivated land is significantly less severe at the head of the basin than at the outlet. Study of the vegetation cover suggests that lower growing shrubs and grasses may be more effective in reducing erosion in this environment than trees. Copyright © 1994 Verlag Chemie, GmbH
Abstract.
1993
Quine TA, Walling DE, Mandiringana OT (1993). An investigation of the influence of edaphic, topographic and land- use controls on soil erosion on agricultural land in the Borrowdale and Chinamora areas, Zimbabwe, based on caesium-137 measurements.
Abstract:
An investigation of the influence of edaphic, topographic and land- use controls on soil erosion on agricultural land in the Borrowdale and Chinamora areas, Zimbabwe, based on caesium-137 measurements
Abstract.
Quine TA, Walling DE (1993). Assessing recent rates of soil loss from areas of arable cultivation in the UK.
Abstract:
Assessing recent rates of soil loss from areas of arable cultivation in the UK
Abstract.
QUINE TA, WALLING DE, ZHANG X (1993). THE ROLE OF TILLAGE IN SOIL REDISTRIBUTION WITHIN TERRACED FIELDS ON THE LOESS PLATEAU, CHINA - AN INVESTIGATION USING CESIUM-137.
Author URL.
Govers G, Quine TA, Walling DE (1993). The effect of water erosion and tillage movement on hillslope profile development: a comparison of field observations and model results.
Abstract:
The effect of water erosion and tillage movement on hillslope profile development: a comparison of field observations and model results
Abstract.
Quine TA, Walling DE (1993). Use of caesium-137 measurements to investigate relationships between erosion rates and topography.
Landscape sensitivity, 31-48.
Abstract:
Use of caesium-137 measurements to investigate relationships between erosion rates and topography
The costs associated with both the on-site and off-site impacts of soil loss from agricultural land highlight the imporance of the identification of landscape sensitivity to erosion. Sensitivity of the landscape to erosion at the micro-scale has been addressed in the present study by assessment of topographic controls upon the processes of erosion and deposition. The caesium-137(137Cs) technique is particulary suited to this task because of the point-specific nature of the long-term erosion rate estimates obtained and the high degree of spatial resolution that is achievable. In this study the pattern of 137Cs-derived soil redistribution rates has been compared with the site topography for five arable fields on a range of soil types from southern UK. Topographic attributes (elevation, slope angle, profile curvature, planform curvature, upslope distance and upslope area) for individual sampling points were extracted from a digital terrain model of each site. The results of the regression analysis were used to identify topographically-defined sensitive areas on the soil types studied. -from Authors
Abstract.
Walling DE, Quine TA (1993). Using chernobyl-derived fallout radionuclides to investigate the role of downstream conveyance losses in the suspended sediment budget of the river severn, United Kingdom.
Physical Geography,
14(3), 239-253.
Abstract:
Using chernobyl-derived fallout radionuclides to investigate the role of downstream conveyance losses in the suspended sediment budget of the river severn, United Kingdom
The sediment budget concept offers a valuable tool for interpreting the processes of erosion and sediment yield operating in a drainage basin. However, it is often difficult to assemble the information necessary to establish a reliable sediment budget. Fallout radionuclides offer considerable potential for this purpose. This contribution describes how measurements of the fate of Chernobyl-derived 134Cs have been used to investigate the role of downstream conveyance losses associated with channel and floodplain storage in the suspended sediment budget of the 6850 km2 basin of the River Severn above Upton on Severn. The results relate to a 3-year period, 1986–1989, and indicate that conveyance losses associated with floodplain and channel storage respectively accounted for 23% and 2% of the total suspended sediment load passing through the main channel system. © 1993 Taylor & Francis Group, LLC.
Abstract.
1992
Davidson DA, Carter SP, Quine TA (1992). An evaluation of micromorphology as an aid to archaeological interpretation.
Geoarchaeology,
7(1), 55-65.
Abstract:
An evaluation of micromorphology as an aid to archaeological interpretation
The detailed description, analysis, and interpretation of field stratigraphy is fundamental to archaeological site interpretation. Investigation of morphology at the macro level can be supplemented by examination under the microscope of soil thin sections prepared from undisturbed samples. Until recently the main emphasis in micromorphological research associated with archaeology has been to assist with paleoenvironmental interpretation. This article reports experience gained from the routine investigation of soil thin sections collected from many archaeological sites throughout Scotland. Greater emphasis is now being given to the investigation of sediment type, anthropogenic features, and nature of disturbance during occupation and post‐depositional processes. Examples from known contexts such as hearths, byres, floors, and anthropogenic soils are given to illustrate the extent to which site formation processes can be elucidated from micromorphological characteristics. It is concluded that the accumulation of data from thin section description of known functional areas will ensure that micromorphology becomes a key research technique in geoarchaeology. Copyright © 1992 Wiley Periodicals, Inc. a Wiley Company
Abstract.
Walling DE, Quine TA, Rowan JS (1992). Fluvial transport and redistribution of Chernobyl fallout radionuclides.
Hydrobiologia,
235-236(1), 231-246.
Abstract:
Fluvial transport and redistribution of Chernobyl fallout radionuclides
Fallout of Chernobyl-derived radionuclides over the UK evidenced marked spatial variation. Relatively high levels were recorded in central Wales, but they declined rapidly to the east and southeast. As a result, the headwaters of the River Severn received substantial inputs of fallout, whereas only low levels were recorded over the middle and lower reaches of its drainage basin. This situation afforded a valuable opportunity to investigate the sediment-associated transport of Chernobyl-derived radiocaesium through the 10 000 km2 drainage basin and its redistribution by fluvial processes. Information on the fallout inputs of radiocaesium has been obtained from the sampling of soil inventories across the basin. Measurements of the radiocaesium content of suspended sediment have been made at several sites on the main river over a period extending from before the Chernobyl disaster through to 1988. Concentrations of caesium-137 in the suspended sediment increased by two orders of magnitude immediately after the accident up to 1450 mBq g -1, declined rapidly subsequently, but remained almost an order of magnitude greater than the pre-Chernobyl levels throughout the remainder of the period (1986-1988). Downstream redistribution of radiocaesium has occurred as a result of deposition of sediment-associated radiocaesium in channel and floodplain sinks. It is estimated that 0.6% of the total fallout input of Chernobyl-derived caesium-134 has been transported out of the basin during the period 1986-1990. Estimates of channel and floodplain storage of sediment-associated caesium-134 at the time of sampling in 1988 and 1989 account for 0.01% and 0.2% of the total fallout input to the basin respectively. © 1992 Kluwer Academic Publishers.
Abstract.
Walling DE, Quine TA, Rowan JS (1992). Fluvial transport and redistribution of Chernobyl fallout radionuclides. In (Ed) Sediment/Water Interactions, 231-246.
Walling DE, Quine TA, He Q (1992). Investigating contemporary rates of floodplain sedimentation.
Lowland floodplain rivers, 165-184.
Abstract:
Investigating contemporary rates of floodplain sedimentation
Uses Cs-127 to estimate rates of sedimentation of floodplains. There are case studies of a 250m stretch of the River Culm floodplain near Exeter, a small part of the floodplain of the River Severn near Tewkesbury just above the junction with the Mill Avon (otherwise known as the Tewkesbury Ham), and the more rapidly accreting floodplain of the River Leira, 25 km NE of Oslo, Norway. -K.Clayton
Abstract.
Quine TA, Walling DE, Zhang X, Wang Y (1992). Investigation of soil erosion on terraced fields near Yanting, Sichuan Province, China, using caesium-137.
Erosion, debris flows and environment in mountain regions. Proc. international symposium, Chengdu, 1992, 155-168.
Abstract:
Investigation of soil erosion on terraced fields near Yanting, Sichuan Province, China, using caesium-137
Much of the agricultural land in the Central Hills area of the Sichuan Basin is at risk from soil erosion by water. An investigation of rates and patterns of soil erosion on agricultural land near Yanting was undertaken using the caesium-137 technique. Erosion of the upper parts of sloping fields was found to be severe, with rates of the order of 20 to 50tha-1 yr-1. However, infield deposition and sediment retrieval from field ditches has led to low net soil loss from the fields with rates of the order of 1 to 6tha-1 yr-1. These data suggest that traditional soil conservation strategies are providing effective protection of much of the cultivated land, but the high potential for soil erosion must be recognized if any change is made in land use or management. -Authors
Abstract.
Walling DE, Quine TA (1992). The use of caesium-137 measurements in soil erosion surveys.
Abstract:
The use of caesium-137 measurements in soil erosion surveys
Abstract.
1991
Walling D, Quine T (1991). Fluvial redistribution of Chernobyl radionuclides.
NERC News,
18, 22-25.
Abstract:
Fluvial redistribution of Chernobyl radionuclides
Most direct deposition of 134Cs and 137Cs in the Severn basin was in the upper headwaters in Wales so that the appearance of caesium in river sediments downstream records fluvial transport of eroded soil. There was also a flush with high values of caesium immediately after the event, no doubt with some in solution and some in suspension. The data therefore throw light on channel storage, flood plain storage and the catchment sediment budget. -K.Clayton
Abstract.
Quine TA, Walling DE (1991). Rates of soil erosion on arable fields in Britain: quantitative data from caesium‐137 measurements.
Soil Use and Management,
7(4), 169-176.
Abstract:
Rates of soil erosion on arable fields in Britain: quantitative data from caesium‐137 measurements
Abstract. Despite a growing awareness that erosion on arable land in Britain is a potential hazard to long‐term productivity, there is still only limited information on the rates involved, particularly long‐term values. Use of the caesium‐137 (137Cs) technique to study soil erosion within arable fields on various soil types at 13 locations in southern Britain has yielded retrospective measurements of the long‐term (c. 30 years) rates of soil loss and the patterns of soil redistribution within the study fields. The range of long‐term rates of net soil loss extends from 0.61 per hectare per year on clay soils in Bedfordshire to 10.5 t per hectare per year on brown sands in Nottinghamshire. The measured rates are compared with other published data for similar soil types and land use, and the implications for long‐term productivity and potential environmental impacts are considered. Copyright © 1991, Wiley Blackwell. All rights reserved
Abstract.
Walling DE, Quine TA (1991). Recent rates of soil loss from areas of arable cultivation in the UK.
Abstract:
Recent rates of soil loss from areas of arable cultivation in the UK
Soil erosion problems have traditionally received little attention in the UK. However, recent intensification of farming practices has led to increased erosion risk in many areas of arable cultivation. Faced with a lack of quantitative data on rates of soil loss in such areas over the past few decades, the "SUP 137" Cesium technique has been applied to estimate recent rates of soil loss from arable fields on a variety of soil types. The results obtained from the 13 sites investigated point to gross erosion rates ranging between 2.2 and 12.2t ha "SUP -1" yr "SUP -1" and net erosion rates in the range 0.6-10.5t ha "SUP -1" yr "SUP -1". It is estimated that rates of soil loss during the past 30-35yr in areas with significant erosion risk may have increased by an order of magnitude or more. Such increases have important implications for long-term crop productivity and increased sediment yields downstream. It is suggested that suspended sediment yields are likely to have doubled in many areas experiencing increased rates of soil loss. (A)
Abstract.
Walling DE, Quine TA (1991). Recent rates of soil loss from areas of arable cultivation in the UK.
Sediment and stream water quality in a changing environment. Proc. symposium, Vienna, 1991, 123-131.
Abstract:
Recent rates of soil loss from areas of arable cultivation in the UK
Soil erosion problems have traditionally received little attention in the UK. However, recent intensification of farming practices has led to increased erosion risk in many areas of arable cultivation. Faced with a lack of quantitative data on rates of soil loss in such areas over the past few decades, the authors have employed the 137Cs technique to estimate recent rates of soil loss from arable fields on a variety of soil types. The results obtained from the 13 sites investigated point to gross erosion rates ranging between 2.2 and 12.2 t ha-1 year-1 and net erosion rates in the range 0.6-10.5 t ha-1 year-1. It is estimated that rates of soil loss during the past 30-35 years in areas with significant erosion risk may have increased by an order of magnitude or more. -from Authors
Abstract.
Walling DE, Quine TA (1991). Recent rates of soil loss from areas of arable cultivation in the UK.
Abstract:
Recent rates of soil loss from areas of arable cultivation in the UK
Soil erosion problems have traditionally received little attention in the UK. However, recent intensification of farming practices has led to increased erosion risk in many areas of arable cultivation. Faced with a lack of quantitative data on rates of soil loss in such areas over the past few decades, the "SUP 137" Cesium technique has been applied to estimate recent rates of soil loss from arable fields on a variety of soil types. The results obtained from the 13 sites investigated point to gross erosion rates ranging between 2.2 and 12.2t ha "SUP -1" yr "SUP -1" and net erosion rates in the range 0.6-10.5t ha "SUP -1" yr "SUP -1". It is estimated that rates of soil loss during the past 30-35yr in areas with significant erosion risk may have increased by an order of magnitude or more. Such increases have important implications for long-term crop productivity and increased sediment yields downstream. It is suggested that suspended sediment yields are likely to have doubled in many areas experiencing increased rates of soil loss. (A)
Abstract.
Walling DE, Quine TA (1991). Recent rates of soil loss from areas of arable cultivation in the UK.
Abstract:
Recent rates of soil loss from areas of arable cultivation in the UK
Abstract.
WALLING DE, QUINE TA (1991). Use of <sup>137</sup>Cs measurements to investigate soil erosion on arable fields in the UK: potential applications and limitations.
Journal of Soil Science,
42(1), 147-165.
Abstract:
Use of 137Cs measurements to investigate soil erosion on arable fields in the UK: potential applications and limitations
Recent awareness of the potential hazard of soil erosion on arable land in the UK has highlighted the lack of reliable data concerning actual rates of soil loss. This lack of information reflects both a low level of interest, and the lack of a simple and generally applicable method of documenting long‐term rates of soil loss. Existing methods involving the use of hazard classification procedures and direct measurement techniques, including erosion plots and field surveys, all possess significant limitations. The use of 137Cs measurements to provide information on rates of soil loss and deposition averaged over the past 30 years would appear to offer considerable potential. The results of applying this approach to three arable fields on contrasting soil types in Britain are reported. These results confirm the viability of the technique and its potential for providing information on patterns and rates of erosion and deposition within individual fields and their overall sediment budgets. Limitations include the restricted size of the areas that can be investigated and the need to take account of additional inputs of 137Cs derived from the Chernobyl accident. Copyright © 1991, Wiley Blackwell. All rights reserved
Abstract.
1990
Walling DE, Quine TA (1990). Calibration of caesium-137 measurements to provide quantitative erosion rate data. Land Degradation and Rehabilitation, 2, 161-175.
Walling DE, Quine TA (1990). Use of Caesium-137 to investigate patterns and rates of soil erosion on arable fields.
Abstract:
Use of Caesium-137 to investigate patterns and rates of soil erosion on arable fields
Abstract.
