Research data.zip

The characteristics of soil erosion and sediment transport can help identify key areas of erosion and sediment yield within a watershed. However, the mechanisms by which vegetation cover and terrace measures influence soil erosion and sediment transport remain unclear. Additionally, the coupling and decoupling effects induced by soil erosion and sediment transport are not clearly described. In this study, the revised universal soil loss equation (RUSLE) and the index of connectivity (IC) were used to visually assess the temporal and spatial variations in soil erosion and sediment transport processes in response to changes in the underlying surface of the Luoyugou watershed from 1986 to 2018. Additionally, the covariation relationship between soil erosion and sediment connectivity was analyzed. The results showed that, driven by a significant increase in vegetation cover and terrace area, soil erosion and IC exhibited a significant decreasing trend from 1986 to 2018 (P<0.01). The area classified as low erosion–low connectivity, which aligns with reduced soil erosion and sediment connectivity, increased from 38.7% to 90.9%. In contrast, the high erosion–high connectivity areas, which are critical for soil erosion control, decreased from 17% to just 0.81%, mainly distributed on steep slopes without forest cover. In areas with severe erosion, there is extensive decoupling (37.8%) of soil erosion and sediment connectivity, while vegetation cover and terraces can reduce the occurrence of decoupling. Overall, vegetation change was the dominant factor in reducing sediment connectivity, accounting for 82.7% of the total contribution, while terraces contributed 17.3%. Determining the relationship between sediment connectivity and soil erosion can identify erosion hotspots within watersheds and provide critical information for watershed management.