[Objective] The distribution and dynamic characteristics of soil and water loss at Wuding River

a typical coarse sediment tributary in the middle reaches of the Yellow River

were analyzed in order to provide a scientific basis for soil and water conservation

ecological environment construction

and high-quality development of the basin in the new period.[Methods] Based on the results of three censuses (1985

1999

and 2011) and national dynamic monitoring of soil and water loss in 2019

the intensity and area of annual soil and water loss at Wuding River basin were extracted

and the spatial and temporal distribution and dynamic change characteristics were analyzed. The variation characteristics of water and sediment in the basin from 1980 to 2018 were analyzed by the Mann-Kendall test based on hydrologic data.[Results] The soil and water loss area in the basin in 2019 was 1.20×104 km2

which was dominated by hydraulic erosion. Wind erosion was mainly observed in the sandstorm area in the northern part of the basin. The sediment transport modulus of the downstream main stream (Baijiachuan-Suide + Dingjiagou section) and the Xiaoheihe River above the Suide was more than three times higher than the average higher than level of the basin

and was the main source of sediment. Compared with 1985

the soil and water loss area decreased by 1.40×104 km2

with a decrease rate of 53.87%. Sediment discharge and runoff showed decreasing trends

and the inflection points appeared in 2007 and 1996

respectively. The spatial distribution of wind erosion was changed from concentrated and contiguous in 1985 to scattered in 2019. The intensity of hydraulic erosion was reduced from Zhaoshiyao to the outlet section of the left bank of the main stream.[Conclusion] Soil and water conservation has effectively curbed soil erosion at Wuding River basin

but soil and water loss is still serious. In the future

it is necessary to strengthen the comprehensive control of soil and water loss by combining research results with work experiences obtained from historical soil and water conservation efforts.