عنوان مجله
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Environmental Resources Research
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کلیدواژهها
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Remote sensing, GIS, Satellite image, Soil erosion, Sediment, Aidoghmoush
watershed
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چکیده
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Soil erosion is among the most important and worldwide environmental issues in
watersheds. Sediment accumulation behind dams requires attempts to minimize their
negative effects. Quantitative data is needed to recognize critical areas which require
urgent measures. Since conventional procedures are time consuming and costly and
usually provide point-based data, there has been a growing tendency towards applying
remote sensing (RS) and geographic information system (GIS) for quantifying soil
erosion at large scales. The current research was carried out in Aidoghmoush watershed
to map soil erosion and sediment using MPSIAC model and RS and GIS technologies.
Several information layers including geology, lithology, topography, soil, land cover and
land-use maps and field data plus prior investigations and satellite imagery were applied
in ArcGIS to map soil erosion in the study area. The results showed that 251 million kg
soil per year is washed out form the watershed by water erosion. In other words, 475 tons
of soil per square kilometer per year get eroded. The results also revealed that slope and
land cover were the most important controlling factors in sedimentation. HU1 and HU4
hydrological units (sub-watersheds) showed the highest sediment per area and were thus
recognized as the most critical areas of the watershed. Conversely, HU3 had the lowest
sediment rate per area.
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