岷江上游典型流域植被水文效应模拟

该文通过研究现有土地覆盖下水文分布的空间格局,及不同植被类型集水区内降雨与径流间的关系,来揭示森林生态系统与水文动态之间相互作用的机制,从而为岷江上游的生态环境评价和区域生态环境保护及恢复提供理论依据和科学指导.在前人研究的基础上,结合先进的地理信息系统和遥感技术,构建岷江流域植被水文模型.模型以水文子模块TOPMODEL为中心,由山地小气候模型MTCLIM和林冠截留模型为其提供水文学参数,研究中水文循环过程涉及植被截留、(实际)蒸散发、降雨入渗和土壤水分动态等.最后将模型应用于岷江上游典型支流——杂古脑流域,对其1995年7—9月的径流特征进行了模拟分析.结果显示,7—9月日径流量总体趋势表现为逐渐降低,径流量对降水响应敏感,基本反映了杂古脑流域雨季的径流变化特征.

Vegetation hydrological effect model of typical watershed in the upstream of Minjiang Valley

This paper studied the hydrological distribution under the existing land cover and the relation between the precipitation and runoff in the watershed with different land covers, discussed the interactional mechanism between forest ecosystem and hydrological dynamics, and provided basis and guidelines for the regional assessment, protection and restoration of ecological environment. Based on the previous study, watershed vegetation hydrological model was constructed, which was intergrated with the GIS technology. The whole model includes three segments, the hydrology model (TOPMODEL), the climate model (MTCLIM) and the vegetation model (the Canopy Interception model). The MTCLIM and the Canopy Interception model can provide the hydrology parameters for the TOPMODEL which is the keystone of the whole model. The hydrologic circulation process of this model includs the vegetation interception, the actual evapotranspiration, rainfall infiltration, and the soil water dynamics. At last, the watershed vegetation hydrological model was applied on the Zagunao watershed, the upstream of the Minjiang Valley. The runoff characteristics of the watershed from July to September in 1995 were simulated. The results show that from July to September, the tendency of the daily runoff decreases gradually, and the runoff has a sensitive response to the precipitation. All of those reflect the runoff characteristics in rainy season in the Zagunao watershed.