荒漠草原2种群落灌丛堆土壤水分的空间特征

Spatial Characteristics of Soil Moisture of 2 Communities in Desert Grassland

【目的】为阐明植被群落与土壤水分空间异质性的关系。【方法】以荒漠草原2种灌丛堆为对象,运用地统计学方法研究了不同灌丛堆(白刺、沙蒿)3种生境(冠下、冠缘、空地)及不同土层土壤水分的空间异质性(c.v.)。【结果】结果表明:土壤水分的空间异质性明显,不同群落类型土壤含水量之间的差异表现为不同群落类型之间大于同一群落不同生境大于同一群落同一生境不同土层,其含水量最大差异分别为162.28%、74.66%、97.44%,在空地20~40 cm土层中,沙蒿沙堆土壤含水量达到白刺的2.62倍;在同一群落之间土壤含水量和水分空间异质性表现为空地>冠缘>冠下;在同一群落同生境中随着土层深度的增加,土壤水分含量增加,变化明显,异质性增大。【结论】荒漠草原自然形成的沙堆微地形地貌引起各非生物要素在空间上的重新分配作用,显著影响土壤水分空间异质性特征。

[ Objective ] The present paper was conducted to illustrate the relationship between spatial heterogeneity of vegetation and soil moisture. [ Method ] Two brush piles were taken as the research object and geography statistics method were adopted to study the different brush pile （ Nitraria tangutorum,Artemisia desertorum） three kinds of habitat （ crown, margin, space） and the spatial heterogeneity of soil moisture （ c. v. ） in different soil layer. [ Result] The spatial heterogeneity of soil moisture（ c. v. ） had a significant difference in different community. The difference of soil moisture content in different community types showed that the difference in different types of community was greater than in the same community in different habitat, which was greater than in the same community in the same habitat but different soil layer. The biggest difference of water content were 162.28 %, 74.66 %, 97.44 %, in the field 20 -40 cm soil layer. The soil moisture of content Artemisia desertorum sand was 2.62 times as much as Nitraria tangutorum ; Soil moisture content and moisture spatial heterogeneity in the same community were characterized by space 〉 margin 〉 crown. In the same community and the same habitat, soil moisture content added with the increase of soil depth, which changed obviously with the increase of heterogeneity. [ Conclusion] Sand micro topography made by desert grassland naturally leads to the redistribution effect of various abiotic factors on the space and ＇affects obviously the spatial heterogeneity feature of soil moisture.