Susceptibility to Gully Erosion: Applying Random Forest (RF) and Frequency Ratio (FR) Approaches to a Small Catchment in Ethiopia
| Autor: | Hanibal Lemma, Eddy J. Langendoen, Martine van der Ploeg, Habtamu Gelagay, Sjoerd E. A. T. M. van der Zee, Saskia Keesstra, Selamawit Amare |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
lcsh:Hydraulic engineering
010504 meteorology & atmospheric sciences Water en Landgebruik Water table Geography Planning and Development Drainage basin Ethiopian highlands Land cover Groundwater table 010501 environmental sciences Aquatic Science Soil type Hydrology and Quantitative Water Management 01 natural sciences Biochemistry Vertisols Soil Bodem Soil Water and Land Use lcsh:Water supply for domestic and industrial purposes soil type lcsh:TC1-978 Nitisols Stream power 0105 earth and related environmental sciences Water Science and Technology Hydrology geography lcsh:TD201-500 geography.geographical_feature_category WIMEK Land use Water and Land Use Bodemfysica en Landbeheer PE&RC Gully erosion mapping gully erosion mapping Bodem Water en Landgebruik groundwater table Watershed management Soil Physics and Land Management Environmental science Drainage density Hydrologie en Kwantitatief Waterbeheer |
| Zdroj: | Water, Vol 13, Iss 216, p 216 (2021) Water 13 (2021) 2 Water, 13(2) Water Volume 13 Issue 2 |
| ISSN: | 2073-4441 |
| Popis: | Soil erosion by gullies in Ethiopia is causing environmental and socioeconomic problems. A sound soil and water management plan requires accurately predicted gully erosion hotspot areas. Hence, this study develops a gully erosion susceptibility map (GESM) using frequency ratio (FR) and random forest (RF) algorithms. A total of 56 gullies were surveyed, and their extents were derived by digitizing Google Earth imagery. Literature review and a multicollinearity test resulted in 14 environmental variables for the final analysis. Model prediction potential was evaluated using the area under the curve (AUC) method. Results showed that the best prediction accuracy using the FR and RF models was obtained by using the top four most important gully predictor factors: drainage density, elevation, land use, and groundwater table. The notion that the groundwater table is one of the most important gully predictor factors in Ethiopia is a novel and significant quantifiable finding and is critical to the design of effective watershed management plans. Results from separate variable importance analyses showed land cover for Nitisols and drainage density for Vertisols as leading factors determining gully locations. Factors such as texture, stream power index, convergence index, slope length, and plan and profile curvatures were found to have little significance for gully formation in the studied catchment. |
| Databáze: | OpenAIRE |
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