Abstract: By using community diversity index and redundancy analysis (RDA), the protozoa communities in the moss crust in Laowangchang gold mine area of southwest Guizhou and their relations with environmental factors were studied. A total of 49 species belonging to 35 genera and 28 families were identified, most of which had low abundance. The variations of the protozoa communities were affected by various kinds of environmental factors, among which, heavy metals pollution and pH were the dominant factors ( P <0.01). The species richness and abundance of the protozoa communities declined with the aggravation of heavy metals pollution, and the effects of chemical factors were more obvious than those of physical factors.

Key words: North China Plain, Winter wheat, Soil respiration rate, Q₁₀ model, Straw manure