水土保持是生态文明建设的重要组成部分,也是反映经济社会发展与生态环境质量动态平衡的重要综合指标。基于近20 a的《中国水土保持公报》,分析了水土流失现状,总结了水土保持工作进展,深入探究了水土流失动态变化成因及水土保持阶段性成效,研究成果对评价水土保持工作成效具有重要理论意义。研究结果表明:①与20世纪80年代末相比,2020年全国水土流失面积下降了26.6%,相较于20世纪初下降了24.4%;②2011年以前水土流失以中度及以上强度为主,2018年以后轻度流失面积占比超过60%;③水土流失综合治理是水土流失面积降低的主要原因;近20 a来,11条主要江河年总输沙量下降了72.4%,年输沙量与累计水土流失治理面积呈显著的负相关关系(R²=0.90)。现阶段我国水土流失治理由“面”向“点”纵深推进,水土保持工作迈入高质量发展。研究成果可为我国水土保持工作评价及水土保持高质量发展提供定量数据和理论基础。

Soil and water conservation plays a crucial role in the construction of ecological civilization. It is also an important indicator that reflects the balance between economic and social development and ecological environment quality. Based on the China Soil and Water Conservation Bulletin published over the past two decades, we analyze the current status of soil and water loss in China, summarize the progresses made in soil and water conservation, and scrutinize the causes of dynamic changes in soil and water loss as well as the effectiveness of soil and water conservation efforts. Our research reveals that: 1) in 2020,the soil erosion area in China reduced by 26.6% from the late 1980s and 24.4% from the beginning of the 20th century; 2) before 2011, soil erosion was moderate or severe, but from 2018, the erosion intensity significantly decreased, and the mild loss area accounted for more than 60%; 3) comprehensive treatment of soil erosion is the primary contribution to the reduction of soil erosion area. Over the past 20 years, the annual sediment discharge of eleven major rivers decreased by 72.4%, and the annual sediment load was significantly negatively correlated with the cumulative soil erosion control area (R²=0.90). At present, China's soil and water conservation efforts are advancing from “surface” to “point” and are moving towards high-quality development. The research results provide quantitative data and theoretical foundations for evaluating soil and water conservation work and promoting high-quality development of soil and water conservation in China.