Abstract: 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×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.

Key words: Rice crab model, Ecological economic analysis, Ecological agriculture