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Lianyuan You - One of the best experts on this subject based on the ideXlab platform.
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Changes in Sediment Yield of the Yellow River basin of China during the Holocene
Geomorphology, 2002Co-Authors: Changxing Shi, Zhang Dian, Lianyuan YouAbstract:This research reconstructs the changes in Sediment Yield of the Yellow River based mainly on a large number of 14 C dates collected from the literature. The total volume of Sediment Yield of the basin during the Holocene is estimated to be 8.0 x 10(12) tons. The annual Sediment Yield had an increasing trend over the Holocene from 0.68, 0.72, 0.79 to 1.0 1 x 10(9) tons over each 2500-year period from the early Holocene to the present. The changes in Sediment Yield are ascribed to both natural and anthropogenic reasons, in which the latter became important in the late Holocene. The mean rate of increase in natural Sediment Yield throughout the Holocene is estimated to be about 0.027 x 10(6) ton/year, and the natural annual Sediment Yield is projected to be 0.95 x 10(9) tons at the present. The increasing trend of natural Sediment Yield is reasoned to be the consequence of evolution of landforms, enhanced by tectonic movement and climatic change in the Loess Plateau, the principal Sediment source of the river, towards a condition favorable to soil erosion. Comparing the estimated annual natural Sediment Yield with the current annual Sediment load of 1.6 x 10(9) tons of the river, it is clear that human activities have augmented natural soil erosion by about 41% in the Yellow River basin. Furthermore, an estimate of the overall pattern of anthropogenic Sediment Yield shows an accelerated increasing trend, which is approximately correspondent with that of population in the Loess Plateau area. (C) 2002 Elsevier Science B.V. All rights reserved.
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Changes in Sediment Yield of the Yellow River basin of China during the Holocene
Geomorphology, 2002Co-Authors: Changxing Shi, Zhang Dian, Lianyuan YouAbstract:This research reconstructs the changes in Sediment Yield of the Yellow River based mainly on a large number of 14C dates collected from the literature. The total volume of Sediment Yield of the basin during the Holocene is estimated to be 8.0 × 10 12 tons. The annual Sediment Yield had an increasing trend over the Holocene from 0.68, 0.72, 0.79 to 1.01 × 10 9 tons over each 2500-year period from the early Holocene to the present. The changes in Sediment Yield are ascribed to both natural and anthropogenic reasons, in which the latter became important in the late Holocene. The mean rate of increase in natural Sediment Yield throughout the Holocene is estimated to be about 0.027 × 10 6 ton/year, and the natural annual Sediment Yield is projected to be 0.95 × 10 9 tons at the present. The increasing trend of natural Sediment Yield is reasoned to be the consequence of evolution of landforms, enhanced by tectonic movement and climatic change in the Loess Plateau, the principal Sediment source of the river, towards a condition favorable to soil erosion. Comparing the estimated annual natural Sediment Yield with the current annual Sediment load of 1.6 × 10 9 tons of the river, it is clear that human activities have augmented natural soil erosion by about 41% in the Yellow River basin. Furthermore, an estimate of the overall pattern of anthropogenic Sediment Yield shows an accelerated increasing trend, which is approximately correspondent with that of population in the Loess Plateau area. © 2002 Elsevier Science B.V. All rights reserved.link_to_subscribed_fulltex
Ramon J. Batalla - One of the best experts on this subject based on the ideXlab platform.
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An appraisal of the Sediment Yield in western Mediterranean river basins
The Science of the total environment, 2016Co-Authors: Cristina Buendia, Albert Herrero, Sergi Sabater, Ramon J. BatallaAbstract:The number of studies assessing soil erosion and Sediment transport has increased with the aim of achieving sustainable land and water management. Mediterranean rivers have been the object of many of these studies due to their naturally high values of Sediment fluxes and a higher vulnerability under future climate scenarios. In this context, we attempt to use empirical relationships to (i) further assess the relation between Sediment Yield and basin scale and (ii) provide an update on the main drivers controlling Sediment Yield in these particular river systems. For this purpose, Sediment Yield data (from reservoir Sedimentation surveys and Sediment transport records) was collected from > 100 locations distributed across the western Mediterranean area, with basin areas ranging from 1 to 100,000 km2. Quantile Regression analysis was used to assess the correlation between basin area and Sediment Yield, while additional basin-scale descriptors were related to Sediment Yield by means of multiple regression analysis. Results showed the complexity in the relationship between basin scale and Sediment Yield, with changes in supply conditions with increasing area introducing uncertainties in the correlation. Despite the large scatter, analysis pointed towards the same direction and area appeared to be the main constrain for the maximum value of Sediment Yield that can be found at a specific basin scale. Results from the multiple regression indicated that variables representing basin's physiography, climate and land use were highly correlated with the basins' Sediment Yield. Also, a better model performance was obtained when using total Sediment Yield instead of specific values (per unit area). Validation showed model instability, potentially due to data limitations and the use of catchments with varying characteristics. Overall, despite providing some insights on the correlation between Sediment Yield and basin-scale characteristics, validation prevented direct extrapolation of the model to other catchments.
V. P. Singh - One of the best experts on this subject based on the ideXlab platform.
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physically based soil erosion and Sediment Yield models revisited
Catena, 2016Co-Authors: Ashish Pandey, Sushil Kumar Himanshu, S K Mishra, V. P. SinghAbstract:Abstract A plenty of models exist for study of the soil erosion and Sediment Yield processes. However, these models vary significantly in terms of their capability and complexity, input requirements, representation of processes, spatial and temporal scale accountability, practical applicability, and types of output they provide. The present study reviews 50 physically based soil erosion and Sediment Yield models with respect to these factors including shortcomings and strengths. The literature generally suggests the use of models like SWAT, WEPP, AGNPS, ANSWERS and SHETRAN for soil erosion and Sediment studies. Most of the developed soil erosion and Sediment Yield models are capable of simulating soil detachment and Sediment delivery processes at hillslope scale; a limited development was found in the field of reservoir siltation and channel erosion processes. The study proposes a guideline for selection of an appropriate model to the reader for a given application or case study. The future research suggested to improve the simulation and prediction capability of physically based soil erosion and Sediment Yield models, and should focus on incorporation of improved global web based weather database, inclusion of Sediment associated water quality and gully erosion simulation module, and improvement in reservoir siltation and channel erosion simulation processes.
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Special Issue on Soil Erosion and Sediment Yield Modeling
Journal of Hydrologic Engineering, 2015Co-Authors: Surendra Kumar Mishra, Ashish Pandey, V. P. SinghAbstract:Soil erosion is one of the most serious environmental problems because it removes fertile soil that is rich in nutrients and, in turn, increases the natural level of Sedimentation in rivers and reservoirs, reducing their storage capacity and life span. Land degradation stems from a combination of factors related to land use, agricultural intensification, and intense rainstorms. For maintaining and improving soil productivity, soil resources need to be conserved for optimal land use. In other words, to restore the productivity of soil and prevent further damage, planning for conservation and management of watersheds become vital. For assessing soil erosion and Sediment Yield from watersheds, several empirical models on the basis of geomorphological parameters have been developed and are available in the literature. Among several methods, the Sediment Yield index (SYI) method and universal soil loss equation (USLE) are extensively used for the estimation of soil erosion and prioritization of watersheds for their treatment. Research in hydrological modeling and related watershed planning issues form a significant component of the prevailing environmental activities. During the last three decades, a number of empirical and conceptual hydrological models have been developed for the prediction of soil erosion and Sediment Yield modeling. Thus, there is a need to have another look at different aspects of soil erosion and Sediment Yield modeling and enhance their understanding for improved practical applications. The present special issue of the Journal of Hydrologic Engineering focuses on soil erosion and Sediment Yield modeling, including the effects of land use/cover changes, extended applications using empirical and physically based soil erosion and Sediment Yield models, and watershed management coupling remote sensing and the geographic information system (GIS). Within this framework, the papers of this special issue have been grouped into the following: studies on the basis of physically based, conceptual, and empirical models; advancement and review; watershed management; and experimental work. Papers titled “Identification of Critical Erosion Watersheds for Control Management in Data Scarce Condition Using the SWAT Model,” “Use of Caesium-137 Measurements and Long-Term Records of Sediment Load to Calibrate the Sediment Delivery Component of the SEDD Model and Explore Scale Effect: Examples from Southern Italy,” “Application of SWAT Model and Geospatial Techniques for Sediment-Yield Modeling in Ungauged Watersheds,” “Soil Erosion and Sediment-Yield Prediction at Basin Scale in Upstream Watershed of Miyun Reservoir,” “Improved Hillslope Erosion Module for the Digital Yellow-River Model,” and “Evaluation of GIS-Based Watershed Model for Streamflow and Sediment-Yield Simulation in the Upper Baitarani River Basin of Eastern India” fall in the category of physically based soil erosion and Sediment Yield modeling. Papers titled “Inductive Group Method of Data Handling Neural Network Approach to Model Basin Sediment Yield,” “Modeling Suspended Sediment Using Artificial Neural Networks and TRMM-3B42 Version 7 Rainfall Dataset,” and “Accounting for Conceptual Soil Erosion and Sediment Yield Modeling Uncertainty in the APEX Model Using Bayesian Model Averaging” deal with conceptual modeling for soil erosion and Sediment Yield. Papers titled “Application of GISCoupled Modified MMF Model to Estimate Sediment Yield on a Watershed Scale,” “Impact of Climate Change on Future Soil Erosion in Different Slope, Land Use, and Soil-Type Conditions in a Part of the Narmada River Basin, India,” and “Spatially Distributed Sheet, Rill, and Ephemeral Gully Erosion” employ empirical models for the estimation of Sediment Yield. The paper “Sediment Graphs Based on Entropy Theory,” which derives an instantaneous unit Sediment graph (IUSG or USG) to determine Sediment discharge and establishes a relation between Sediment Yield and runoff volume, exhibits an advancement in the field of Sediment Yield modeling. Conversely, the paper “Geographic Variation of USLE/RUSLE Erosivity and Erodibility Factors” provides a comprehensive review on the subject. The papers “Integrated Modeling Approach to the Response of Soil Erosion and Sediment Export to Land-Use Change at the Basin Scale,” “Evaluating the Impact of the Spatial Distribution of Land Management Practices on Water Erosion: Case Study of a Mediterranean Catchment,” and “Sediment Fingerprinting for Calibrating a Soil Erosion and Sediment-Yield Model in Mixed Land-Use Watersheds” deal with watershed management. The papers “Establishing a Soil Loss Threshold for Limiting Rilling,” “Transport Capacity of Overland Flow with High Sediment Concentration,” “Modeling Rainfall Erosivity by Measured Drop-Size Distributions,” “Modeling Rill Erosion at the Sparacia Experimental Area,” “Rapid Weathering and Erosion of Mudstone Induced by Saltwater Migration near a Slope Surface,” and “Rain Microstructure and Erosivity Relationships under Pressurized Rainfall Simulator” are on the basis of experimental work. The aim of this issue is to present high-quality technical articles representing the most recent developments in the field of soil erosion and Sediment Yield modeling, including practical applications. This special issue is expected to become the first in a sequence of future issues on this topic.
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SCS-CN-based modeling of Sediment Yield
Journal of Hydrology, 2005Co-Authors: Surendra Kumar Mishra, V. P. Singh, J.v. Tyagi, Ranvir SinghAbstract:Coupling the soil conservation service curve number (SCN-CN) method with the universal soil loss equation (USLE), a new model is proposed for the estimation of the rainstorm-generated Sediment Yield from a watershed. The coupling is based on three hypotheses: (1) the runoff coefficient is equal to the degree of saturation, (2) the potential maximum retention can be expressed in terms of the USLE parameters, and (3) the Sediment delivery ratio is equal to the runoff coefficient. The proposed Sediment Yield model is applied to a large set of rainfall-runoff-Sediment Yield data (98 storm events) obtained from 12 watersheds of different land uses (urban, agricultural, and forest). For all watersheds the computed Sediment Yield is found to be in good agreement with the observed values. The results and analysis of model application show that the model has considerable potential in field.
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Tank Model for Sediment Yield
Water Resources Management, 2005Co-Authors: V. P. SinghAbstract:A tank model consisting of three tanks was developed for prediction of runoff and Sediment Yield. The Sediment Yield of each tank was computed by multiplying the total Sediment Yield by the Sediment Yield coefficients; the Yield was obtained by the product of the runoff of each tank and the Sediment concentration in the tank. The Sediment concentration of the first tank was computed from its storage and the Sediment concentration distribution (SCD); the Sediment concentration of the next lower tank was obtained by its storage and the Sediment infiltration of the upper tank; and so on. The SCD, caused by the incremental source runoff (or the effective rainfall), was obtained by the theory of the instantaneous unit Sediment graph (IUSG) and a Sediment routing function. Using the SCD, the Sediment Yield was computed from the tank model as well as by the IUSG model. The Sediment Yield obtained from the tank model was then compared with that from the IUSG model. Finally, the tank model was verified on an upland watershed in northwestern Mississippi.
Changxing Shi - One of the best experts on this subject based on the ideXlab platform.
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Changes in Sediment Yield of the Yellow River basin of China during the Holocene
Geomorphology, 2002Co-Authors: Changxing Shi, Zhang Dian, Lianyuan YouAbstract:This research reconstructs the changes in Sediment Yield of the Yellow River based mainly on a large number of 14 C dates collected from the literature. The total volume of Sediment Yield of the basin during the Holocene is estimated to be 8.0 x 10(12) tons. The annual Sediment Yield had an increasing trend over the Holocene from 0.68, 0.72, 0.79 to 1.0 1 x 10(9) tons over each 2500-year period from the early Holocene to the present. The changes in Sediment Yield are ascribed to both natural and anthropogenic reasons, in which the latter became important in the late Holocene. The mean rate of increase in natural Sediment Yield throughout the Holocene is estimated to be about 0.027 x 10(6) ton/year, and the natural annual Sediment Yield is projected to be 0.95 x 10(9) tons at the present. The increasing trend of natural Sediment Yield is reasoned to be the consequence of evolution of landforms, enhanced by tectonic movement and climatic change in the Loess Plateau, the principal Sediment source of the river, towards a condition favorable to soil erosion. Comparing the estimated annual natural Sediment Yield with the current annual Sediment load of 1.6 x 10(9) tons of the river, it is clear that human activities have augmented natural soil erosion by about 41% in the Yellow River basin. Furthermore, an estimate of the overall pattern of anthropogenic Sediment Yield shows an accelerated increasing trend, which is approximately correspondent with that of population in the Loess Plateau area. (C) 2002 Elsevier Science B.V. All rights reserved.
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Changes in Sediment Yield of the Yellow River basin of China during the Holocene
Geomorphology, 2002Co-Authors: Changxing Shi, Zhang Dian, Lianyuan YouAbstract:This research reconstructs the changes in Sediment Yield of the Yellow River based mainly on a large number of 14C dates collected from the literature. The total volume of Sediment Yield of the basin during the Holocene is estimated to be 8.0 × 10 12 tons. The annual Sediment Yield had an increasing trend over the Holocene from 0.68, 0.72, 0.79 to 1.01 × 10 9 tons over each 2500-year period from the early Holocene to the present. The changes in Sediment Yield are ascribed to both natural and anthropogenic reasons, in which the latter became important in the late Holocene. The mean rate of increase in natural Sediment Yield throughout the Holocene is estimated to be about 0.027 × 10 6 ton/year, and the natural annual Sediment Yield is projected to be 0.95 × 10 9 tons at the present. The increasing trend of natural Sediment Yield is reasoned to be the consequence of evolution of landforms, enhanced by tectonic movement and climatic change in the Loess Plateau, the principal Sediment source of the river, towards a condition favorable to soil erosion. Comparing the estimated annual natural Sediment Yield with the current annual Sediment load of 1.6 × 10 9 tons of the river, it is clear that human activities have augmented natural soil erosion by about 41% in the Yellow River basin. Furthermore, an estimate of the overall pattern of anthropogenic Sediment Yield shows an accelerated increasing trend, which is approximately correspondent with that of population in the Loess Plateau area. © 2002 Elsevier Science B.V. All rights reserved.link_to_subscribed_fulltex
Cristina Buendia - One of the best experts on this subject based on the ideXlab platform.
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An appraisal of the Sediment Yield in western Mediterranean river basins
The Science of the total environment, 2016Co-Authors: Cristina Buendia, Albert Herrero, Sergi Sabater, Ramon J. BatallaAbstract:The number of studies assessing soil erosion and Sediment transport has increased with the aim of achieving sustainable land and water management. Mediterranean rivers have been the object of many of these studies due to their naturally high values of Sediment fluxes and a higher vulnerability under future climate scenarios. In this context, we attempt to use empirical relationships to (i) further assess the relation between Sediment Yield and basin scale and (ii) provide an update on the main drivers controlling Sediment Yield in these particular river systems. For this purpose, Sediment Yield data (from reservoir Sedimentation surveys and Sediment transport records) was collected from > 100 locations distributed across the western Mediterranean area, with basin areas ranging from 1 to 100,000 km2. Quantile Regression analysis was used to assess the correlation between basin area and Sediment Yield, while additional basin-scale descriptors were related to Sediment Yield by means of multiple regression analysis. Results showed the complexity in the relationship between basin scale and Sediment Yield, with changes in supply conditions with increasing area introducing uncertainties in the correlation. Despite the large scatter, analysis pointed towards the same direction and area appeared to be the main constrain for the maximum value of Sediment Yield that can be found at a specific basin scale. Results from the multiple regression indicated that variables representing basin's physiography, climate and land use were highly correlated with the basins' Sediment Yield. Also, a better model performance was obtained when using total Sediment Yield instead of specific values (per unit area). Validation showed model instability, potentially due to data limitations and the use of catchments with varying characteristics. Overall, despite providing some insights on the correlation between Sediment Yield and basin-scale characteristics, validation prevented direct extrapolation of the model to other catchments.
