五台山清水河流域植被垂直带水循环过程研究

五台山为华北地区最高峰(海拔3058 m),发源于五台山的清水河流域,海拔梯度大,植被垂直分异显著,目前关于植被垂直带的水循环过程及其相互之间的差异研究尚显不足。为此,利用分布式水文模型WEP-L模拟清水河流域水循环过程,分析不同植被垂直带的水循环过程。结果表明:受气温显著升高影响,高海拔地区的季节性冻土消退、活动层变厚及土壤蓄水容量增加,促进降水入渗。海拔1500 m以下区域蒸散发主要受降水影响,而海拔1600 m以上区域则主要受能量的影响。不同植被垂直带的水循环过程差异显著,径流系数表现为:耕地亚高山草甸荒漠草地常绿针叶灌木林落叶阔叶林。研究结果可为山区流域水资源高效利用和生态建设提供科学依据。

Study on water cycle process in vegetation vertical belts of the Qingshui River basin in Wutai Mountain

Wutai Mountain is the highest mountain in North China (with the altitude of 3058m). The originates at the Wutai Mountain, the Qingshui River basin has a high gradient of elevation, with a significant vegetation vertical differentiation. However, there is still insufficient research on the water cycle processes and their differences in the vegetation vertical belts. Therefore, we used the distributed hydrological model WEP-L to simulate the hydrological cycle process in the Qingshui River basin, and analyzed water cycle processes of different vegetation vertical belts. Results show that rising temperature thickened the active permafrost layers, which leaded to increase of the soil water storage capacity, and finally resulted in the increase of precipitation infiltration. The regions with elevations lower than 1500m were water limited, and the regions with elevations higher than 1600m were energy limited. The hydrological process of different vegetation vertical belts are significantly different, and runoff coefficients for different vegetation vertical belts could be sorted as:farmland > desert grassland > subalpine meadow > evergreen needle-leaf forest > deciduous broad-leaf forest. These results may provide scientific basis for efficient utilization of water resources and ecological construction in mountainous watershed.