浑善达克沙地榆树疏林生态系统的空间异质性

榆树疏林生态系统是浑善达克沙地的重要组分之一运用生物统计学(U检验和相关性分析等)和地统计学的方法(半方差分析和空间局部插值),研究了浑善达克沙地榆树疏林生态系统的土壤有机质(SOM)、土壤全氮(STN)、土壤pH(SpH)、土壤含水量(SWC)和草本层盖度(HC)的空间异质性,并探讨了它们之间以及与榆树空间位置的关系.研究结果表明:SOM、STN、SpH、SWC和HC的分布格局均具有明显的空间异质性和空间自相关性,它们的空间格局与榆树的空间分布有明显的相关性.在此基础上,应用空间局部插值法,绘制了各个性状的空间等值分布图.通过等值分布图直观的分析了榆树与各研究性状的空间格局的关系,探讨榆树对疏林生态系统土壤性状和草本层植物分布的空间异质性的影响,以及榆树下成为草原上的沃岛(fertility island)的原因.

Spatial Heterogeneity of Ulmus pumila Open Forest Ecosystem in Otindag Sandy Land

Ulmus pumila open forest ecosystem plays an important role in Otindag Sandy Land. Using biostatistics ( U test and Pearson correlation analysis) and geostatistics (Semivariogram analysis and Kriging interpolation), the spatial heterogeneity of soil organic matter (SOM), soil total nitrogen (STN), soil pH (SpH), soil water content (SWC), and the correlations between them, as well as their relationships with herbaceous coverage (HC) and Ulmus pumila were studied. The results showed that spatial heterogeneity and spatial dependence were apparent in SOM, STN, SpH, SWC and HC. With Kriging interpolation in the sampling area, the contour maps for these properties were drawn. Using the contour maps, the relationship between Ulmus pumila and spatial heterogeneity of the studied properties was investigated. The possible reason for the formation of fertility island under the Ulmus pumila trees in the ecosystem was discussed.