严重的水土流失造成土壤中大量养分流失和土壤质量下降，导致水环境面污染,因此，坡地水土养分流失不仅是一个农业问题，也是一个水环境问题。本项目针对水土养分流失研究中存在的科学问题，以降雨条件下坡地水土养分迁移动力过程为研究对象，以坡地土壤养分传输动力学理论为基础，以试验研究与数学模拟为手段，通过系统研究降雨特征、坡面特征、土壤特征、种植结构、其他调控措施等对水土养分流失特征的影响，揭示黄土坡地水土养分流失机制及各种控制措施作用机理，提出描述坡地水土养分流失特征综合动力学指标，建立描述次降雨或时段降雨下坡地养分流失的概念模型和水土养分传输动力过程的动力学模型，以及描述一定时段内水土养分流失的综合模型，丰富坡地物质迁移的动力学理论，为优化控制措施和预测坡地水土养分流失提供科学理论与方法。研究成果将在国内外学术期刊发表，发表学术论文30篇，其中SCI收录论文15篇。

Serious water and soil losses not only cause amount of nutrient loss in soils and soil quality degradation, but also lead to water body pollution. Therefore, water, soil and nutrient loss involves in the agriculture production and the water circumstance protection. In the project, according to the exiting scientific problems in the studies on water, soil and nutrient loss on slope land, the dynamic processes of water, soil and nutrient transports over slope land are considered as the main research objects. The approaches of experimental studies and mathematical simulations will be adopted to study the effects of rainfall features, slope feature, planting structures and other regulating methods on water, soil and nutrient loss processes over slope land based on the dynamic theories of nutrient transport in soils. Features of water, soil and nutrient losses on loess slope and acting mechanisms of several of regulation methods will be comprehensively analyzed, and the comprehensive indicators describing water, soil and nutrient loss over loess slope land will be established. The conceptual models describing water, soil and nutrient loss processes during rainfall, the dynamic models describing the dynamical processes of water, soil and nutrient transport over loess slope land and the comprehensive models for the water, soil and nutrient loss during a certain time interval will also be established. The study results will enrich the theory of matter transport over slope land and provide the scientific theories and methods for optimizing regulating methods and predicting the loss amount of water, soil and nutrients on slope land. The research results will be published in journals at home and abroad, and 30 relevant papers will be published in journals and the 15 papers will be published in the journals collected by SCI citation index groups.