摘要
【目的】探讨祁连山排露沟小流域鲜黄小檗灌丛穿透雨特征及其影响因素,为定量评价祁连山鲜黄小檗灌丛的生态水文效应提供数据支撑。【方法】基于灌丛种群特征调查,选取3处代表性的鲜黄小檗灌丛,沿冠层枝条辐散方向选取观测断面,在每个断面上布置承雨器,对穿透雨和冠层结构指标进行测定,分析穿透雨与降雨量和冠层结构特征的关系。【结果】(1)试验期间,单株鲜黄小檗的平均穿透雨率为55.1%。部分观测点的穿透雨率大于100%,这主要是由于降雨在冠层的作用下发生了聚集效应。(2)穿透雨量与降雨量之间呈线性关系(P<0.01),穿透雨率与降雨量之间呈对数函数关系(P<0.05)。(3)受冠层水平结构影响,平均穿透雨率从距基部10cm处的25.93%单调递增至距基部90 cm处的74.45%;其中,距基部50~70 cm之间增加值最大,占总增加值的41.19%。随着冠层厚度的增大,平均穿透雨率呈减小的趋势。叶面积指数在一定程度上影响穿透雨的空间分布,且降雨量越小影响程度越明显。【结论】在降雨性质相同的情况下,冠层结构特征是影响灌丛冠下穿透雨空间分布的重要因素。
【Objective】In this study,the characteristics of throughfall and the factors influencing it were examined at the scale of individual Berberis diaphana shrubs in the small watershed of Pailugou,the Qilian Mountain.The findings will facilitate quantification of the ecohydrological functions of the shrub in the Qilian Mountain.【Method】On the basis of an investigation of population characteristics,three representative individuals of B.diaphana were selected as sample shrubs on the lower part of a slope at an elevation of 2 600 m.Three radial sections along the branch radial direction were set up for each sample shrub and containers were installed at each radial section to collect the throughfall from each rainfall event.The throughfall for each rainfall event and parameters of canopy structure were measured.Based on these measurements,then we analyzed the relationship between throughfall and the canopy parameters.【Result】（1） During the entire experimental period,the mean throughfall ratio of individual shrubs was 55.1%.However,at some sample sites,a throughfall ratio of greater than 100% was observed.This latter observation could be attributed to the fact that rainfall is concentrated by the canopy.（2） The increasing throughfall of B.diaphana shrubs showed a significantly positive linear correlation with the increasing rainfall amount（P〈0.01）; however,the relationship between the throughfall ratio and the rainfall amount could be fitted with a logarithmic curve（P〈0.05）.（3） With respect to the horizontal structure of the canopy,the mean throughfall ratio increased from 25.93% at a distance of 10 cm from the shrub core to 74.45% at a distance of 90 cm from the shrub core.The largest increment in throughfall ratio was recorded at a distance of 50-70 cm from the core,which accounted for 41.19% of the total increment for the distance of 10-90 cm from the shrub core.Themean throughfall ratio decreased with increasing canopy thickness.Leaf area index（LAI） affected the throughfall ratio to some extent,with the effect being stronger when the rainfall was light.【Conclusion】The characteristics of canopy structure,such as canopy thickness,LAI and branch angle,are key factors influencing the spatial distribution of throughfall in B.diaphana shrubs.
作者
万艳芳
刘贤德
于澎涛
马瑞
王顺利
王彦辉
李晓青
WAN Yanfang LIU Xiande YU Pengtao MA Rui WANG Shunli WANG Yanhui LI Xiaoqing(Forestry College, Gansu Agricultural University, Lanzhou 730070, China Academy of Water Resources Conservation Forest in Qilian Mountain of Gansu Province, Zhangye 734000, China Research Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, Beijing 100091, China)
出处
《南京林业大学学报（自然科学版）》
CAS
CSCD
北大核心
2017年第2期97-102,共6页
Journal of Nanjing Forestry University：Natural Sciences Edition
基金
国家自然科学基金项目(91225302,91425301,31360201,41461004)
关键词
鲜黄小檗灌丛
冠层结构
穿透雨
降雨量
祁连山
Berberis diaphana shrub
canopy structure
throughfall
rainfall
the Qilian Mountains
