Erosion in the Himalayas on catchment scale. Integrative remote sensing assesment

Erosion in active mountain belts is one of the key questions in geomorphology. Remote sensing can be a powerful tool to predict erosion on a quantitative scale and helps to understand the near-surface processes involved. One of the major limits in these kinds of environments is the lack of ground truth information and its inaccessibility. Here we present an integrated approach in order to validate remote sensing applications with on-site information in small catchments. Image classification (MLC) on SPOT-5 data is applied to map land-use and relate it spatially with typical erosion rates. Precipitation measurements from the Tropical Rain Measuring Mission (TRMM) are compared with real precipitations from a rain gauge network. Denudation rates derived from land-use classifications (soil erosion) are related to absolute denudation rates calculated from suspended sediment concentrations. Our results outline the intricacy of competing processes in active mountain environments and that it is possible to measure spatial erosion from remote sensing information. Nevertheless, the spatial resolution, especially of TRMM data is limiting the small-scale erosion prediction.