scholarly journals ASSESSING THE PERFORMANCE OF A SPATIALLY DISTRIBUTED SOIL EROSION AND SEDIMENT DELIVERY MODEL (WATEM/SEDEM) IN NORTHERN ETHIOPIA

2011 ◽  
Vol 24 (2) ◽  
pp. 188-204 ◽  
Author(s):  
N. Haregeweyn ◽  
J. Poesen ◽  
G. Verstraeten ◽  
G. Govers ◽  
J. de Vente ◽  
...  
Keyword(s):  
Soil Erosion ◽  
Northern Ethiopia ◽  
Sediment Delivery ◽  
Delivery Model ◽  
Spatially Distributed

scholarly journals Soil erosion and sediment delivery in a mountain catchment under scenarios of land use change using a spatially distributed numerical model

2012 ◽  
Vol 16 (5) ◽  
pp. 1321-1334 ◽  
Author(s):  
L. C. Alatorre ◽  
S. Beguería ◽  
N. Lana-Renault ◽  
A. Navas ◽  
J. M. García-Ruiz
Keyword(s):  
Land Use ◽  
Soil Erosion ◽  
Sediment Yield ◽  
Model Calibration ◽  
Global Optimum ◽  
Model Parameters ◽  
Sediment Delivery ◽  
Yield Data ◽  
Good Convergence ◽  
Spatially Distributed

Abstract. Soil erosion and sediment yield are strongly affected by land use/land cover (LULC). Spatially distributed erosion models are of great interest to assess the expected effect of LULC changes on soil erosion and sediment yield. However, they can only be applied if spatially distributed data is available for their calibration. In this study the soil erosion and sediment delivery model WATEM/SEDEM was applied to a small (2.84 km2) experimental catchment in the Central Spanish Pyrenees. Model calibration was performed based on a dataset of soil redistribution rates derived from point 137Cs inventories, allowing capture differences per land use in the main model parameters. Model calibration showed a good convergence to a global optimum in the parameter space, which was not possible to attain if only external (not spatially distributed) sediment yield data were available. Validation of the model results against seven years of recorded sediment yield at the catchment outlet was satisfactory. Two LULC scenarios were then modeled to reproduce land use at the beginning of the twentieth century and a hypothetic future scenario, and to compare the simulation results to the current LULC situation. The results show a reduction of about one order of magnitude in gross erosion (3180 to 350 Mg yr−1) and sediment delivery (11.2 to 1.2 Mg yr−1 ha−1) during the last decades as a result of the abandonment of traditional land uses (mostly agriculture) and subsequent vegetation recolonization. The simulation also allowed assessing differences in the sediment sources and sinks within the catchment.

Geographic information system-coupling sediment delivery distributed modeling based on observed data

2014 ◽  
Vol 70 (3) ◽  
pp. 495-501 ◽  
Author(s):  
S. E. Lee ◽  
S. H. Kang
Keyword(s):  
Information System ◽  
Geographic Information System ◽  
Soil Erosion ◽  
Soil Loss ◽  
Geographic Information ◽  
Delivery Ratio ◽  
Sediment Discharge ◽  
Sediment Delivery Ratio ◽  
Sediment Delivery ◽  
Spatially Distributed

Spatially distributed sediment delivery (SEDD) models are of great interest in estimating the expected effect of changes on soil erosion and sediment yield. However, they can only be applied if the model can be calibrated using observed data. This paper presents a geographic information system (GIS)-based method to calculate the sediment discharge from basins to coastal areas. For this, an SEDD model, with a sediment rating curve method based on observed data, is proposed and validated. The model proposed here has been developed using the combined application of the revised universal soil loss equation (RUSLE) and a spatially distributed sediment delivery ratio, within Model Builder of ArcGIS's software. The model focuses on spatial variability and is useful for estimating the spatial patterns of soil loss and sediment discharge. The model consists of two modules, a soil erosion prediction component and a sediment delivery model. The integrated approach allows for relatively practical and cost-effective estimation of spatially distributed soil erosion and sediment delivery, for gauged or ungauged basins. This paper provides the first attempt at estimating sediment delivery ratio based on observed data in the monsoon region of Korea.

scholarly journals Soil erosion and sediment delivery in a mountain catchment under land use change: using point fallout <sup>137</sup>Cs for calibrating a spatially distributed numerical model

2011 ◽  
Vol 8 (6) ◽  
pp. 11131-11170 ◽  
Author(s):  
L. C. Alatorre ◽  
S. Beguería ◽  
N. Lana-Renault ◽  
A. Navas ◽  
J. M. García-Ruiz
Keyword(s):  
Land Use ◽  
Soil Erosion ◽  
Sediment Yield ◽  
Model Calibration ◽  
Global Optimum ◽  
Model Parameters ◽  
Sediment Delivery ◽  
Good Convergence ◽  
Spatially Distributed ◽  
Order Of Magnitude

Abstract. Soil erosion and sediment yield are strongly affected by land use/land cover (LULC). Spatially distributed erosion models are useful tools for comparing erosion resulting from current LULC with a number of alternative scenarios, being of great interest to assess the expected effect of LULC changes. In this study the soil erosion and sediment delivery model WATEM/SEDEM was applied to a small experimental catchment in the Central Spanish Pyrenees. Model calibration was carried out based on a dataset of soil redistribution rates derived from 137Cs inventories along three representative transects, allowing capture differences per land use in the main model parameters. Model calibration showed a good convergence to a global optimum in the parameter space. Validation of the model results against seven years of recorded sediment yield at the catchment outlet was satisfactory. Two LULC scenarios where then modeled to reproduce the land use at the beginning of the twentieth Century and a hypothetic future scenario, and to compare the simulation results to the current LULC situation. The results show a reduction of about one order of magnitude in gross erosion (3180 to 350 Mg yr−1) and sediment delivery (11.2 to 1.2 Mg yr−1 ha−1) during the last decades as a result of the abandonment of traditional land uses (mostly agriculture) and subsequent vegetation re-colonization. The simulation also allowed assessing differences in the sediment sources and sinks within the catchment.

Disentangling the effect of past and present agroforestry practices in modifying landscapes of Mediterranean mountains

2021 ◽  
Author(s):  
Ivan Lizaga ◽  
Leticia Gaspar ◽  
Borja Latorre ◽  
Ana Navas
Keyword(s):  
Soil Erosion ◽  
Management Practices ◽  
Ground Truth ◽  
Land Uses ◽  
Catchment Scale ◽  
Sediment Delivery ◽  
Ensemble Technique ◽  
Erosion Rates ◽  
Soil Redistribution ◽  
Spatially Distributed

&lt;p&gt;Soil erosion and sediment delivery to rivers are important drivers for land degradation and environmental change in mountain agroecosystems.&amp;#160; These factors are especially severe in areas affected by intermittent heavy rainfalls after dry periods, and human practices such as deforestation or clearcutting practices. Many Mediterranean mountain environments underwent conversion of rangelands into croplands during the previous centuries increasing the risk of erosion. After land abandonment the process was gradually reversed during the middle of the 20&lt;sup&gt;th&lt;/sup&gt;&lt;sub&gt;&lt;/sub&gt;century, allowing the recovery of natural land cover and reduced soil erosion rates. To further control the high erosion rates, several afforestation programs introduced pine forests at the headwater of most Mediterranean mountain catchments transforming the landscape by terracing and reducing the sediment connectivity. However, nowadays, forests&amp;#8217; different management could lead to high erosion rates and subsequent landscape modifications. To understand the possible effect of these practices together with the current agricultural management, we have combined the strength of empirical data and spatially distributed modelling. Surface soil samples from different land uses were collected in a representative catchment at the foot of Santo Domingo range at the border of the central Ebro River valley. The study catchment was mostly cultivated at the beginning of the 19&lt;sub&gt;th&lt;/sub&gt; century but changed to rangeland and pine afforestation in the last 50 years. The remaining croplands are predominated by rainfed agriculture that leaves soils mostly unprotected from June to January when erosive storms occur. The main land uses are croplands, pine afforestation, scrubland and Mediterranean forest.&lt;/p&gt;&lt;p&gt;In this study, we propose an ensemble technique composed of &lt;sup&gt;137&lt;/sup&gt;Cs derived soil redistribution rates as specific point values and as a calibration tool for the widely used WaTEM/SEDEM sediment delivery model. Thus, by the use of ground truth and modelled data we aim to i) apply the WaTEM/SEDEM model at the catchment scale and calibrate it with &lt;sup&gt;137&lt;/sup&gt;Cs derived soil redistribution rates for finding an optimal set of input parameters; ii) examine the effect of clearcutting and agricultural practices on the total erosion; iii) compare the modelled results with recently calculated sediment apportionments by using the sediment fingerprinting technique.&lt;/p&gt;&lt;p&gt;Our findings highlight the use of spatially distributed models combined with &lt;sup&gt;137&lt;/sup&gt;Cs derived rates as a powerful tool to understand the driving factors of soil erosion in the last decades and to delineate the hotspot areas that could suffer high erosion if subjected to certain management practices.&lt;/p&gt;

An uncertainty-based framework for incorporating sediment source fingerprinting into spatially-distributed soil erosion model testing

2020 ◽  
Author(s):  
Pedro Velloso Gomes Batista ◽  
J Patrick Laceby ◽  
Jessica Davies ◽  
Teotônio Soares de Carvalho ◽  
Diego Tassinari ◽  
...  
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Soil Erosion ◽  
Model Testing ◽  
Sediment Source ◽  
Sediment Delivery ◽  
Sediment Loads ◽  
Spatially Distributed ◽  
Delivery Models ◽  
Grid Based

&lt;p&gt;Evaluating the usefulness of spatially-distributed soil erosion and sediment delivery models is inherently difficult. Complications stem from the uncertainty in models and measurements of system responses, as well as from the scarcity of commensurable spatial data for model testing. Here, we present an approach for evaluating distributed soil erosion and sediment delivery models, which incorporates sediment source fingerprinting into model testing within a stochastic framework. We applied the Generalized Likelihood Uncertainty Estimation (GLUE) methodology to the Sediment Delivery Distributed (SEDD) model for the Mortes River catchment (~6600 km&amp;#178;) in Southeast Brazil. Sediment concentration measurements were used to estimate long-term sediment loads with a sediment rating curve. Regression uncertainty was propagated with posterior simulations of model coefficients. A Monte Carlo simulation was used to generate SEDD model realizations, which were compared against limits of acceptability of model errors derived from the uncertainty in the curve-estimated sediment loads. The models usefulness for identifying the sediment sources in the catchment was assessed by evaluating behavioral model realizations against sediment fingerprinting source apportionments. Accordingly, we developed a hierarchical tributary sampling design, in which sink sediments were sampled from multiple nodes in the main river channel. The relative contributions of the main sub-catchments in the basin were subsequently estimated by solving the fingerprinting un-mixing model with a Monte Carlo simulation. Results indicated that gauging station measurements of sediment loads were fairly uncertain (average annual specific sediment yields = 0.47 &amp;#8211; 11.95 ton ha&lt;sup&gt;-1&lt;/sup&gt; yr&lt;sup&gt;-1&lt;/sup&gt;). This led to 23.4 % of SEDD model realizations being considered behavioral system representations. Spatially-distributed estimates of sediment delivery to water courses were also highly uncertain, as grid-based absolute errors of SEDD results were hundredfold the median of the predictions. A comparison of SEDD outputs and fingerprinting source apportionments revealed an overall agreement between modeled contributions from individual sub-catchments to sediment loads, although some large discrepancies were found in a specific tributary. From a falsificationist perspective, the SEDD model could not be rejected, as many model realizations were behavioral. The partial agreement between fingerprinting and SEDD results provide some conditional corroboration of the models capability to identify the sources of sediments in the catchment, at least with some degree of spatial aggregation. However, the uncertainty in the grid-based outputs might dispute the models usefulness for actually quantifying sediment dynamics under the testing conditions. For management purposes, both SEDD and fingerprinting results indicated that most of the sediments reaching the hydroelectric power plant reservoir located at the outlet of the Mortes River originated from mid and upper catchment tributaries. The convergence of model results therefore evince that reducing reservoir sedimentation rates requires widespread soil conservation efforts throughout the catchment, instead of local/proximal interventions. Ultimately, we have shown how sediment source fingerprinting can be incorporated into the evaluation of spatially-distributed soil erosion and sediment delivery models while considering the uncertainty in both models and observational data.&lt;/p&gt;

Soil Erosion Studies in Northern Ethiopia

2008 ◽  
pp. 73-100 ◽  
Author(s):  
Lulseged Tamene ◽  
Paul L. G. Vlek
Keyword(s):  
Soil Erosion ◽  
Northern Ethiopia

Enhancement of the SATEEC Soil Erosion and Sediment Modeling System with Better Sediment Delivery Ratio Module

2007 ◽  
Author(s):  
Ki-Sung Kim ◽  
Kyoung Jae Lim ◽  
Joongdae Choi ◽  
Bernie Engel ◽  
Ji-Hong Jeon ◽  
...  
Keyword(s):  
Soil Erosion ◽  
Delivery Ratio ◽  
Sediment Delivery Ratio ◽  
Sediment Delivery

scholarly journals Influence of land management on soil erosion, connectivity, and sediment delivery in agricultural catchments: Closing the sediment budget

2019 ◽  
Vol 30 (18) ◽  
pp. 2257-2271 ◽  
Author(s):  
Sophie C. Sherriff ◽  
John S. Rowan ◽  
Owen Fenton ◽  
Phil Jordan ◽  
Daire Ó hUallacháin
Keyword(s):  
Soil Erosion ◽  
Land Management ◽  
Sediment Budget ◽  
Sediment Delivery ◽  
Agricultural Catchments

Effectiveness of stone bunds in controlling soil erosion on cropland in the Tigray Highlands, northern Ethiopia

2005 ◽  
Vol 21 (3) ◽  
pp. 287-297 ◽  
Author(s):  
Desta Gebremichael ◽  
J. Nyssen ◽  
J. Poesen ◽  
J. Deckers ◽  
Mitiku Haile ◽  
...  
Keyword(s):  
Soil Erosion ◽  
Northern Ethiopia
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