Abstract:
Objective In response to the difficulties in obtaining spatially continuous precipitation data and the low accuracy of estimating vegetation cover management factors in high vegetation cover areas in previous soil erosion studies, this paper attempted to introduce multi-source remote sensing data for spatial-scale soil erosion evaluation.
Methods This paper improved the modified soil erosion model (RUSLE) based on the precipitation erosion factor (R) and vegetation cover management factor (C) obtained from GPM_3IMERGM and LANDSAT8 image data, and completed the remote sensing mapping of soil erosion status in the study area using the improved RUSLE model.
Results The results showed that the total soil erosion in the study area was 5.12 × 107 t a−1, the average soil erosion modulus was 7.38 t hm−2 a−1, and the total area affected by soil erosion was 1841.86 km2, accounting for 24.77% of the total land area. In terms of soil erosion grades, the erosion intensity was generally slight and mild, and soil and water protection was generally good. In terms of spatial distribution, the layout of different erosion classes showed a combination of patchy distribution and point-block distribution. Several administrative districts in central and southern Guangzhou had a milder erosion status than those in the periphery of the city and northern administrative districts.
Conclusion The introduction of GPM satellite data and EVI index significantly improved the accuracy of the estimation of two key factors and soil erosion intensity in the RUSLE model, and the results could provide a theoretical basis and practical reference for the regional soil and water conservation and ecological environment construction work in Guangzhou.