黄河源区基流变化及其植被响应研究

黄河源区是我国最大的自然保护区之一,但近年来存在一系列严重的生态环境退化现象。来自地下水的基流量的变化正是植被生长环境变化的直接反映,因此开展基流量变化研究对于高寒干旱区的生态环境变化规律认识与环境恢复都具有重要的科学价值。黄河源区地下水位变化对植被生长具有直接的影响,研究结果表明：1956-1998年来自地下水的基流量总体上呈现枯—丰—枯的变化规律,表明了源区地下水位呈现低—高—低的总体变化规律;源区的基流量与地表植被的生长之间具有良好的相关性,汛期降水之后,地下水对植被生长的影响逐渐增大。

Changes of Base Flow in the Source Region of Yellow River and the Response of Its Vegetation

The source region of Yellow River is one of the largest nature reserves in China, but in recent years, there are a series of serious environmental degradation. Based on the fact that the base flow is the direct indication of vegetation growth and environment change, so the research on the base flow change has important scientific value for the environment restoration in the alpine arid regions. Variations of ground water level of the source region of Yellow River has a direct influence on the growth of vegetation, the study results indicate that： （ 1 ） Base flow which comes from groundwater generally shows a Low water - Plentiful - Low water variation in the periods of 1956 - 1998, indicating that the groundwater level of the source region of Yellow River varies from low to high to low ; （ 2 ） There is a good correlation between the base flow and the growth of vegetation in the source region of Yellow River, the influence of groundwater on vegetation growth was gradually increased after rain- fall in the flood season.