祁连山区森林景观格局对水文生态效应的影响

在地理信息系统ArcGIS环境下,结合1987-2001年的水文资料,用Spatial Analyst、Hydrologic Modeling等扩展模块,对祁连山中段北坡大野口河流域和海潮坝河流域的景观格局与水文特征进行比较分析,结果表明:大野口河流域的景观组分以低海拔的草地和乔木林占优势,草地所占面积最大,整个景观较为破碎;海潮坝河流域的景观组分以高海拔的裸地和灌丛占优势,裸地所占面积最大,景观破碎化程度相对较低。大野口河流域的蒸散发占降水量的61%,流域径流系数为0.39;而海潮坝河流域的蒸散发占降水量的41%,流域径流系数为0.59。研究表明,导致两流域生态水文效应相差较大的主要原因是两流域不同的景观格局。

Forest landscape pattern and its eco-hydrological effects of the Qilian Mountains in northwest China

Using the model of Arc GIS program and the hydroloyical databases for 1981 to 2001, we analyze the landscape pattern and hydrological features of Dayekou river catchment (DYK) and Haichaoba river catchment(HCB) which are located at the Qilian mountains in northwest China. The results show that grassland and Picea crassifolia forest in DYK are the main landscape elements, and more important work in eco-hydrological process, while shrubs and bare land in HCB are the main landscape elements and of importance in eco-hydrological process. In DYK, the evapotranspiration is 61% of the rainfall, and the runoff coefficient is 0.39% whereas in HCB, the evapotranspiration is of the rainfall 41%, and the runoff is 0.59%. The coefficient study indicates that different forest landscape pattern will bring on different eco-hydrological effects in the arid mountain areas.