祁连山东段灌丛穿透雨特征

Throughfall Characteristics of Shrub in Eastern Qilian Mountain

为进一步认识高寒植被灌丛生态水文过程机制,以祁连山东段的山生柳、硬叶柳和绣线菊灌丛为研究对象,于2017年7—9月份对3种灌丛的穿透雨进行了监测,分析山生柳、硬叶柳和绣线菊灌丛冠层穿透雨量和穿透雨率特征。结果表明:山生柳、硬叶柳和绣线菊的总穿透雨量分别为105.7、123.3、159.2 mm,分别占降雨总量的47.3%、55.1%和71.2%。穿透雨量与降雨量呈显着性的正相关(P<0.001),穿透雨率随着降雨量的增加而增加。当降雨量为最高的46.8 mm时,山生柳、硬叶柳和绣线菊对应的穿透雨达到最大值,分别为19.9、26.1、32.7 mm,一次性降雨下不同植被类型穿透雨均值由大到小的排序为绣线菊、硬叶柳、山生柳。穿透雨与灌丛类型呈正相关关系,而与冠幅、基径、枝条数、叶面积和盖度等呈负相关关系。

In order to further understand the eco-hydrological process mechanism of alpine vegetation shrubs, the Salix oritrepha Schneid., Salix sclerophylla Anderss. and Spiraea salicifolia L. shrubs in the eastern part of Qilian were selected as the research objects, and the penetrating rain on three shrubs from July 1 to September 30, 2017 was monitored to analyze the characteristics of throughfall and throughfall ratio of the three shrubs canopy. The total throughfalls of S. oritrepha, S. sclerophylla and S. salicifolia were 105.7 mm, 123.3 mm and 159.2 mm, accounting for 47.3%, 55.1% and 71.2% of the total rainfall,respectively. There is a significant positive correlation between throughfall and rainfall(P<0.001), and the throughfall ratio increases with the increase of rainfall. When the rainfall reached the highest 46.8 mm, the throughfall corresponding to Salix oritrepha, Salix sclerophylla and Spiraea salicifolia reached the maximum, which were 19.9, 26.1 and 32.7 mm, respectively. Different vegetation types penetrated under one-time rainfall. The descending order of rain average size is Spiraea salicifolia, Salix sclerophylla and Salix oritrepha. Throughfall is positively correlated with shrub types, but negatively correlated with canopy width, basal diameter, the number of branches, leaf area and coverage.