Spatial Analysis on Surface Deformation by Soil Erosion in the Chinese Loess Plateau Using Insar Techniques

Monitoring the surface deformation over the loess hills could help us understand the dynamics of soil erosion, the extent of anthropogenic impacts, and the mitigation methods for the potential damage to local ecosystems, agricultural production, socioeconomic infrastructure, water quality, and air quality in the Loess Plateau and the surrounding areas. The objectives of this study were to comprehend the spatial soil erosion dynamics over wide areas by using remote sensing and other related techniques, and also to confirm the validity of the techniques and the involved challenges. Wuqi County of Shaanxi Province in which soil and water have been intensively conserved at the national level was chosen as a study area. A Differential Interferometric Synthetic-Aperture Radar (D-InSAR) was applied using L-band ALOS-1/PALSAR-1 images to measure the surface deformation at several loess hills between 2008 and 2010. In the results, the surface deformation data, inclusive of the spatial effects of soil erosion across a wide area, was collected. By investigating these surface deformations, we observed that the degree of soil erosion depended on the slope direction and slope angle. In addition, the intensity of soil erosion vary by the features of hilly terrains, so that it can be considered that the location of the loess hills could be a factor. These findings provided us with important information that could help for the development of effective spatial land-use plans, which would aid current efforts in soil and water conservation.