Ronny Berndtsson
Professor, Dep Director, MECW Dep Scientific Coordinator
Soil erosion estimation based on rainfall disaggregation
Author
Summary, in English
Abstract in Undetermined
Soil loss estimation remains one of the most difficult research tasks all over the world. Current simulation tools are still not detailed enough to allow for realistic scenarios to handle soil erosion problems. A common problem is the lack of rainfall data at a sufficient level of detail. The present study uses a cascade disaggregation model to generate short time scale rainfall data, needed to calculate the erosivity index in erosion modeling. The model is used to determine the spatial soil loss rate by the Revised Universal Soil Loss Equation and a GIS approach. Comparison between observed and generated data in terms of erosive rainfall characteristics shows that the erosivity factor is over-estimated. This is caused by an overestimation of short rainfall events. Consequently, different duration limits beyond which erosive events could be considered within the generated series were used to estimate the model performance curve. This provided a suitable duration limit needed to reproduce the observed erosivity. The results showed that generated series only considering rainfall events superior than 90 min are appropriate. This procedure provides a soil loss rate less than 10% under-estimation. Moreover, using Masson, Wischmeier-Smith's and recent erosion limit intervals gave a realistic spatial erosion distribution. The results are promising and can be used to better manage erosion-prone soils.
Soil loss estimation remains one of the most difficult research tasks all over the world. Current simulation tools are still not detailed enough to allow for realistic scenarios to handle soil erosion problems. A common problem is the lack of rainfall data at a sufficient level of detail. The present study uses a cascade disaggregation model to generate short time scale rainfall data, needed to calculate the erosivity index in erosion modeling. The model is used to determine the spatial soil loss rate by the Revised Universal Soil Loss Equation and a GIS approach. Comparison between observed and generated data in terms of erosive rainfall characteristics shows that the erosivity factor is over-estimated. This is caused by an overestimation of short rainfall events. Consequently, different duration limits beyond which erosive events could be considered within the generated series were used to estimate the model performance curve. This provided a suitable duration limit needed to reproduce the observed erosivity. The results showed that generated series only considering rainfall events superior than 90 min are appropriate. This procedure provides a soil loss rate less than 10% under-estimation. Moreover, using Masson, Wischmeier-Smith's and recent erosion limit intervals gave a realistic spatial erosion distribution. The results are promising and can be used to better manage erosion-prone soils.
Department/s
- MECW: The Middle East in the Contemporary World
- Centre for Advanced Middle Eastern Studies (CMES)
- Division of Water Resources Engineering
- LTH Profile Area: Water
Publishing year
2012
Language
English
Pages
102-110
Publication/Series
Journal of Hydrology
Volume
436
Document type
Journal article
Publisher
Elsevier
Topic
- Water Engineering
- Other Social Sciences
Keywords
- Cascade disaggregation model
- Short time scale rainfall
- Fractal
- Erosivity factor
- RUSLE/GIS approach
- Spatial erosion distribution
Status
Published
ISBN/ISSN/Other
- ISSN: 0022-1694