毛乌素沙地半固定沙丘油蒿种群对土壤湿度空间异质性的响应

将统计学和地统计学方法相结合，探讨了毛乌素沙地半固定沙丘土壤湿度空间异质性与油蒿种群空间异质性之间的关系. 结果表明，在块尺度（80 m×80 m）上，油蒿密度和生物量的空间异质性受制于土壤湿度的空间异质性，尤其油蒿生物量的空间异质性与土壤湿度的空间异质性呈显著正相关关系.表明在半固定沙丘阶段，土壤湿度的空间异质性决定油蒿种群的空间异质性. 由于沙丘地形对降水量的再分配在土壤湿度分布中的作用，土壤湿度和油蒿种群空间异质性相互作用的结果为地形的缀块性→土壤湿度分布的缀块性→油蒿种群分布的缀块性→油蒿生物量和密度的缀块性.

Responses of Artemisia ordosica population to soil moisture spatial heterogeneity on semi-fixed dune of Mu Us sandy land

Spatial heterogeneity affects the functions and processes of ecosystems. By the methods of statistics and geostatistics, this paper approached the relationships between the spatial heterogeneities of Artemisia ordosica and soil moisture on the semi-fixed dune of Mu Us sandy land. The results showed that on plot-scale (80 m x 80 m), the spatial heterogeneity of A. ordosica biomass and density was dependant on that of soil moisture, and in particular, there existed a significant positive correlation between the biomass and the moisture, indicating that on semi-fixed dune, soil moisture played a decisive role in the spatial heterogeneity of plant population. Due to the redistribution of precipitation on sand dune, the outcomes of the interactions between the spatial heterogeneities of soil moisture and A. ordosica population were assumed as patchness of terrain --> patchness of soil moisture distribution --> patchness of A. ordosica population distribution --> patchness of A. ordosica biomass and density.