白梭梭(Haloxylon persicum)灌丛下雾凇的散布格局及其对土壤含水量的影响  

Rime Dispersal Pattern under Haloxylon persicum Canopy and Its Effect on Soil Moisture Content in Early Winter

作　　者：尹本丰 张元明[1] 陶冶[1] 

机构地区：[1]中国科学院新疆生态与地理研究所干旱区生物地理与生物资源重点实验室,新疆乌鲁木齐830011 [2]中国科学院大学,北京100049

出　　处：《中国沙漠》2015年第4期951-958,共8页Journal of Desert Research

基　　金：国家重点基础研究发展计划项目(2014CB954202);国家自然科学基金项目(U1203301)

摘　　要：雾凇是古尔班通古特沙漠冬季常见的天气现象,荒漠植物具有较强的捕获雾凇的能力。雾凇作为隐匿性降水对荒漠植被的生长具有极其重要的作用。本研究调查了初冬无雪期2株不同大小的白梭梭(Haloxylon persicum)灌丛下雾凇散落的分布格局,分析了雾凇对灌丛下土壤含水量的影响。结果表明:2株白梭梭灌丛下雾凇均表现出偏向下风坡散落的格局;雾凇量和土壤含水量的空间分布格局均服从高斯模型,并呈现出由灌丛基部向外先增加后减少的趋势;雾凇量与雾凇融化后土壤含水量的结构变异系数均在92%以上,表明二者的空间变异主要是灌丛引起的空间自相关造成的;2株白梭梭灌丛下的土壤含水量与雾凇散落量均为显著正相关,表明散落的雾凇确实增加了灌丛下的土壤含水量。因此,雾凇散落将有利于灌丛下生物结皮的生长,促进结皮(尤其是苔藓结皮)的选择性分布。Rime is a common weather phenomenon in the Gurbantonggut Desert,China.Desert plants have a stronger ability capturing the rime through capture the tiny drop of water.As an occult precipitation,rime plays an important role as condensation water for the vegetation of deserts.Till now,research on the spatial distribution pattern of the rime scattered from desert shrubs and its influence on soil moisture content(SMC)have not been reported.In this study,the spatial distribution pattern of the rime scattered from the Haloxylon persicum canopies with different sizes were investigated in early winter without snow,and the influence of rime on SMC were analyzed.The results showed that the rime scattered from two shrubs both represented the pattern towards the leeward slope.The spatial distribution patterns of both rime and SMC under two shrubs fitted the Gaussian model,and the contents of rime and SMC presented the tendency of increasing firstly and then decreasing from the shrub root(center of canopy)to the outside.The structure variation coefficients of rime and SMC of two shrubs were more than 92%,indicating that the spatial variability between variables was strong and the spatial differences are mainly caused by spatial autocorrelation causing by shrub canopy.Meanwhile,the SMCs under both two shrubs were positively correlated with the scattered rime content significantly,indicating that the rime scattered from shrub improved the SMC reliably.Therefore,the results suggest that the rime will be of advantage to the growth of biological soil crusts under shrub canopy,and also promotes the selective distribution of crusts,especially for moss crusts.

关 键 词：雾凇 白梭梭(Haloxylon persicum) 空间异质性 土壤含水量 生物结皮 干旱区 

分 类 号：Q948[生物学—植物学]