Soil erosion trends and factor correlations in the black soil region of Northeast China Plain based on RUSLE model

Based on GIS technology,the Revised Universal Soil Loss Equation(RUSLE) was used to estimate soil erosion rates and characterize soil erosion in Harbin City,Heilongjiang Province,from 2001 to 2020. The Theil-Sen Median trend analysis combined with the Mann-Kendall(MK)test was applied to assess soil erosion trends. Correlation analyses were conducted by three factors:rainfall,vegetation cover,and soil. The results indicate that the overall soil and water conservation status in Harbin is good,with soil erosion dominated by slight and mild level. Over the study period,erosion first decreased and then increased,with the increase being predominantly non-significant. A clustered slightly significant increase was observed in the northeastern part of the region. The cover and management factor shows a significant negative correlation with soil erosion,whereas both the rainfall erosivity factor and the support practice factor exhibit a significant positive correlation. Plains are more resistant to soil erosion than mountainous areas. The factors influencing soil erosion,in descending order of impact,are the cover and management factor,rainfall erosivity factor,and support practice factor. This quantitative study of the spatiotemporal characteristics of soil erosion in Harbin provides a scientific reference for protecting black soil resources,maintaining ecosystem balance,preventing land degradation,and promoting sustainable development in Northeast China.