滇池流域不同下垫面降雨产流特征及产水量模拟研究

Taken Dianchi Lake basin which is faced with surface water shortage and deterioration of water environment as the research object, and applying multidisciplinary research methods and means concerning hydrology, landscape ecology, remote sensing and geographic information system,the project plans to go into the spatial distribution and the seasonal variation of the rainfall quantificationally in the basin, to study out the hydrographical parameters scientifically on different underlying surface conditions and explore the corresponding rainfall runoff processes particularly through artificial rainfall experiments, soil sampling and analysis. After that, to set up the rational rainfall runoff simulation models that apply to different land cover types for simulating and calculating the partition-based water yield. Furthermore, on account of the environmental differences in Dianchi Lake basin, the project intends to reveal the spatial differentiation of rainfall runoff, and to carry out the utilization potential assessment of the rainwater resources based on the partition so as to provide scientific evidence for rainwater resources utilization and ecological environment improvement in the whole basin. Finally, the project would put forward a more refined research pattern for the synthetical calculation and statistics of rainfall runoff in Dianchi Lake Basin, and which also could be supplied as a reference for the related researches in other mountain watersheds that have the similar environmental conditions in southwestern China's monsoon area.

本项目以地表水资源短缺、水环境恶化的滇池流域为研究对象，采用水文学、景观生态学、遥感和地理信息系统等多学科的研究方法和手段，深入研究流域降雨空间分布场并定量分析其季变特征；拟重点通过人工降雨观测试验、土样采集分析，科学率定不同下垫面的水文地理参数并探究其降雨产流过程；合理构建适于不同土地覆被类型的降雨产流模拟模型，分类计算产流水量；并结合流域内部环境差异，分析降雨产流的空间分异特征，分区评估雨水资源的利用潜力，为全流域雨水资源利用、生态环境整治提供科学依据；提出适用于滇池流域更为精细化的降雨产流综合测算的研究模式，并为西南季风区环境条件类似山地流域的相关研究提供参考和借鉴。

本项目以地表水资源短缺、水环境恶化的滇池流域为研究对象，采用了气象与气候学、水文学、景观生态学 、遥感和地理信息系统等多学科的研究方法和手段。在分析流域降雨空间分布特征、划分土地利用/覆被类型的基础上，划分了22个降雨分区和6种土地利用类型；并对流域内阔叶林、针叶林和针阔混交林的降雨林冠截留特征进行了分析和模拟，探讨了降雨因林冠截留而损失的雨量评估的新方法。基于红壤、紫色土、黄棕壤等3种代表性土类的人工模拟降雨观测试验，研讨了流域主要土壤类型坡面降雨-产流-产沙的关系；并依托试验数据，经过参数优化，率定了不同土地利用类型的CN值；据此构建了适用于滇池流域的SCS-CN降雨产流模型。结合流域各降水分区的降水水平、兼顾土地覆被类型和植被的降雨截留量，分析降雨产流的空间分异特征；汇总测算了2017-2021年的降雨产流量；进而评估了流域雨水资源的利用潜力（约6亿立方米）。本研究提出了适用于滇池流域更为精细化的降雨产流综合测算方法，研究成果为全流域雨水资源利用、生态环境整治提供了科学依据；并可为西南季风区环境条件类似山地流域的相关研究所参考和借鉴。