祁连山北坡主要草地类型的土壤水分动态研究

Study on soil moisture dynamics of the main grassland types in the northern slopes of Qilianshan Mountains

祁连山北坡天然草地植被以高寒草原、山地草甸、山地草甸草原、山地草原和山地荒漠草原等类型为主,对这5种典型草地类型土壤水分进行了观测,结果显示:不同草地类型生长季土壤水分动态变化规律基本一致,主要受降水量及其时间分配的影响,土壤水分的季节动态可划分为消耗期、积累期、消退期和稳定期4个时段;5类草地群落土壤水分垂直变化与土层深度的关系并不完全一致,其剖面变化可分为活跃层、调节层和相对稳定层;土壤水分储量以山地草甸最高,其它依次为山地草甸草原、高寒草原、山地草原、山地荒漠草原。

Based on the research on soil water of five main vegetation types： alpine pastureland, mountainous meadow, mountainous meadow pastureland, mountainous pastureland, mountainous desert pastureland in the northern slopes of the Qilianshan mountains, the results show that the seasonal dynamics of soil moisture is delimited into four stages： consumptive stage, accumulating stage, receding stage, stable stage. Seasonal change tendency of soil moisture of different vegetation types in growing period is almost identical, which is affected by precipitation and its temporal distribution. The relationship between the vertical change of soil water and soil depth is not uniform absolutely in the five vegetation types and it can be classified into three layers： active layer, regulative layer and relatively stable layer. Soil water storage of mountainous meadow is the highest of the 5 vegetation types, and others are in order of mountainous meadow pastureland, alpine pastureland, mountainous pastureland, and mountainous desert pastureland.