Abstract: To understand the effects of slope location on the community structure of soil fauna in Eucalyptus grandis plantation, an investigation was made in the soil fauna in 3 E.grandis plantations at different slope locations in the hilly area of Sichuan Province from January to October 2009. A total of 392762 individuals were observed, belonging to 146 groups, 7 phyla, 16 classes, and 31 orders. The community composition, trophic group, diversity, and seasonal dynamics of soil fauna in the plantations all varied with slope. The abundance of macro-fauna, xeric meso- and micro-fauna, saprophagous macro-fauna, and omnivorous xeric meso-and micro-fauna increased with the decrease of slope, indicating that soil fauna had sensitive responses to the soil environmental factors affected by slope. Significant differences in the diversity of soil saprophagous macro-fauna and hygrophilous meso- and micro-fauna were observed at different slope locations, suggesting that these two faunal groups could be used as the indicators of the habitat heterogeneity of E. grandis plantations at different slope. Overall, slope location had definite effects on the community structure and distribution of soil fauna in the E. grandis plantations, but the effects were not statistically significant.

Key words: soil fauna, slope location, community structure, trophic group, diversity, Eucalyptus grandis plantation, rhizosphere effect, soil nutrient, soil microbe, Stipa grandis, typical steppe.