Impacts of soil conservation measures on runoff and soil loss in a hilly region, Northern China

Impacts of soil conservation measures on runoff and soil loss have not been fully considered in the regions where soil erosion control and water resource are both important. In the present study, six years (2014-2019) of runoff and soil loss data from 19 runoff plots in the upstream catchment of the Miyun Reservoir in Beijing, the capital of China were employed to do this work. Results indicated that runoff and soil loss from the plots differed greatly, depending on land use, soil conservation measure and slope degree. Bare and cultivated plots without any soil conservation measures suffered the highest soil loss rate of over 3000 t km(-2) yr(-1) with higher runoff depth, followed by grass plots (1274.1 t km(-2) yr(-1)), orchard plots (127.2 t km(-2) yr(-1)), and shrub plots (65.3 t km(-2) yr(-1)). H and SLR approached zero on the forest plots. Over 80% of the sediment and runoff were intercepted by shrub, grass, and terraced plots, with SLRs much less than the soil tolerance value (i.e., 200 t km(-2) yr(-1)) in the study region. Contour tillage plots on gentle slope can also intercept over 90% sediment, while allowing most of the generated runoff to run downslope. Implementation of soil conservation measures must be cautious in the study area. Water-saving soil conservation measures should be given priority to in the study region. Contour tillage should be promoted on gentle slopes, and terrace size should be considered on different slopes when it is implemented. The vegetation coverage such as forest, shrub, and grass should be lesser to release more runoff downslope. Soil conservation measures are still required on bare and cultivated slopes. This study can help to implement reasonable soil conservation measures in this and similar regions in the world.