典型农耕区有效降水与植被生长互馈关系及动态模拟研究

During the vegetation growth, the formation of effective precipitation will be affected by the variation of canopy characteristics, while the water supply (mainly from effective precipitation) of soil moisture for deep roots will determine the water environment of vegetation growth. That is to say, feedback mechanism exists between effective precipitation and vegetation growth. Quantitatively revealing this kind of feedback mechanism is the key proof to establish targeted and accurate irrigation system. This research will take typical crops (winter wheat and summer maize) in Pihe Basin as the object. Controlled experiments, prototype observation and numerical simulation will be utilized as the key support to identify the response of vegetation growth to effective precipitation and the impact of precipitation and vegetation on effective precipitation. Based on this, the feedback mechanism between effective precipitation and the vegetation growth will be revealed, and the effective dynamic simulation model in the soil-crop unit scale will be established. The field prototype observation experiments will be used to modify the established model, so as to form the dynamic effective precipitation simulation model in the cropland scale. This research will provide scientific proof for agricultural area of the Pihe Basin to establish accurate irrigation system.

植被生长过程中伴随的冠层特征变化会对有效降水的形成产生影响，而有效降水对于根系深层土壤水分的补给又决定着植被生长的水分环境，即有效降水与植被生长之间存在着互馈关系，定量揭示这一关系是制定靶向性和精准性灌溉制度的关键依据。本项目以淠河流域典型农作物冬小麦和夏玉米为研究对象，以控制试验、原型观测和数值模拟为关键支撑，识别植被生长对有效降水的响应，以及降水和植被对有效降水的影响，在此基础上，揭示有效降水与植物生长之间的互馈关系，构建土体-作物单元尺度下有效降水动态模拟模型，并结合野外原型观测实验，对所构建的模型进行修正，形成农田尺度下有效降水动态模拟模型。以期通过本项目的研究，为淠河流域农耕区制定精准灌溉制度提供科学依据。

植被生长过程中伴随的冠层特征变化会对有效降水的形成产生影响，而有效降水对于根系深层土壤水分的补给又决定着植被生长的水分环境，即有效降水与植被生长之间存在着互馈关系，定量揭示这一关系是制定靶向性和精准性灌溉制度的关键依据。本项目以淠河流域为研究对象，采用原型观测与数值模拟相结合的方式，识别了有效降水与植被互馈关系，揭示了“前期有效降水→植被→有效降水”链式影响过程，构建了有效降水递推模拟方程，相对于传统的有效降水静态模拟模型，适用于有效降水和植被生长趋势的预测。