Evaluation of soil erosion and analysis of driving factors in the Ganguyi Watershed of Yanhe River from 1980 to 2020
The daily rainfall data,DEM data,soil type data,sediment content data and multi period NDVI data were used to study the soil erosion dynamics and driving factors in the Ganguyi Watershed of the Yanhe River in the past 41 years before and after the im-plementation of the national ecological rehabilitation project of returning farmland to forest and grassland based on the Revised General Soil Loss Equation(RUSLE)and geographic detectors.The results showed that,from 1980 to 2020,the overall soil erosion intensity in the study area showed a fluctuating trend,with an average erosion modulus of 6 746.30 t/(km2·a),5 740.28 t/(km2·a),6 389.56 t/(km2·a),5 450.46 t/(km2·a)and 5 480.56 t/(km2·a)in 1980,1990,2000,2010 and 2020,respectively.From 1980 to 2000,the overall erosion intensity in the study area gradually increased,and the proportion of erosion areas at the strong level and above gradual-ly increased,which was characterized by"erosion increase and upgrading".After 2000,the intensity of soil erosion in the study area began to decrease,and the area of erosion at the strong level and above decreased,which was characterized by"erosion reduction and degradation".The intensity of soil erosion in the study area increased with the increase of slope.At the same time,it was found that 1 000～1 200 m and 1 200～1 400 m were the main elevation zones for erosion occurrence in the study area.The explanatory power of land use type factors was most prominent in 2020,indicating that the implementation of the project of returning farmland to forests and grasslands had a significant effect.The conversion of large areas of farmland to forests and grasslands was the main reason for the de-crease in soil erosion intensity in the research area after 2000.The synergistic effect of various influencing factors on soil erosion was significantly stronger than that of a single factor.
soil erosionRevised Universal Soil Loss Equation(RUSLE)geographic detectordriving factorGanguyi Watershed of Yanhe River
NETL
NSTL
万方数据
