Abstract: To understand the effects of tillage mode on the community structure and diversity of soil meso- and micro-fauna, a field experiment was conducted at the National Observation Station of Agroecology System in Hailun of Northeast China. Five tillage modes including no tillage, reduced tillage, mold board tillage, combined tillage, and rotary tillage were chosen, and the modified Tullgren method were adopted to extract soil fauna from 0-15 cm soil layer, with the community structure and vertical distribution of soil meso- and micro-fauna analyzed. There existed differences in the community structure and vertical distribution of soil meso- and micro-fauna under different tillage modes. Liodidae and Oribatellidae were the dominant families under the five tillage modes, and the similarities of the community structure of soil meso- and micro-fauna were higher between moldboard plough and rotary tillage and between no tillage and reduced tillage. Combined tillage kept the surface accumulation of soil fauna. The diversity, evenness, and dominance of the soil fauna under reduced tillage were higher than those under other tillage modes. It was suggested that tillage mode could affect the community structure of soil meso- and micro-fauna, and conservation tillage (combined tillage and reduced tillage) could benefit the stability of soil faunal community structure and kept the surface accumulation of soil fauna in vertical distribution.

Key words: alpine timberline ecotone, decomposition rate, litter, initial quality, lignin/N.