长江上游水库消落带土壤侵蚀机理及其生态利用模式

水库消落带在稳定库岸、净化水质、美化景观、保育生物多样性和保障水库安全运行与河流健康等方面发挥关键作用；但特殊的水文节律导致其土壤侵蚀动力过程复杂，反季节长时间淹水环境导致其生态利用极为困难。本项目针对长江上游水库消落带土壤侵蚀剧烈、生态脆弱、生境胁迫等特点，选择干、支流不同类型土质消落带为研究对象，利用野外调查、遥感动态监测、核素示踪、磁性示踪、CT探测、野外定位观测与试验、室内模拟实验和模型评价等方法，阐明长江上游水库消落带特殊水文节律下土壤侵蚀时空分异规律和土壤-植被特征演变规律；揭示复合营力耦合作用下的消落带土壤侵蚀过程机理；采用“生物多样性-生态系统结构-过程与功能-服务”级联式概念框架，建立基于消落带生态利用的植物资源质量及生态价值评价方法；提出消落带生态利用对策与生态重建模式。研究结果可丰富和扩展水土保持科学基础理论，为长江上游水库消落带环境整治与生态利用提供科学依据。

The reservoir riparian zone provides key functions in bank stabilization, water quality purification, landscape aesthetic values, biodiversity conservation, and maintaining safely operation of reservoirs and health of river systems. But the specific hydrological regime leads to complicated mechanic processes of soil erosion, while anti-seasonal prolonged flooding makes it extremely difficult for eco-using of this landscape. With regards to intensive soil erosion, ecological fragility, and extreme habitat condition in the reservoir riparian zone on the upper Yangtze River, and by using field survey, remote-sensing dynamic monitoring, nuclide tracing, magnetic tracing, CT, on-site field observation and experiment, in-door simulation and modelling and targeting different types of soil riparian zone along the mainstream and tributaries, this study aims to: (1) reveal the spatial and temporal pattern of soil erosion under the specific hydrological regime in the reservoir riparian zone on the upper Yangtze River, and soil-vegetation evolution pattern; (2) illustrate the processes and underlying mechanisms of soil erosion driven by integration of multiple forces; (3) formulate an evaluation framework for plant resources and ecological values under the eco-using orientation by applying the “biodiversity-ecosystem structure-processes and functions-ecosystem services” conceptual framework; (4) suggest eco-using strategies and ecological reinforcement modes. Potential results could enrich and expand basic theory of soil conservation sciences and provide scientific guidelines for environmental improvement and eco-using of reservoir riparian zone on the upper Yangtze River.