Abstract:There are several ways available to measure diversity of biological communities,but the methods of diversity index and species-abundance pattern are the common ones used.To get to know characters of a community,the species-abundance pattern method is more efficient than the diversity index method.In this paper species-abundance distribution of soil animal communities in different positions of a sloping field was studied with a view of introducing a species-abundance distribution model into the study on soil fauna and disclosing in depth the spatial pattern of soil fauna diversity in a micro-region.Based on investigation of the macrofauna and mesofauna communities in piedmont,and the lower,middle and upper parts of a sloping field in the Zuojia Nature Reserve,Jilin Province,China,and by using the log-series distribution model,log-normal distribution model and broken-stick model for fitting of the curves of the species-abundance of the macrofauna and mesofauna communities in different parts of the sloping field,with species-abundance as index,spatial distribution patterns of species-abundance of the two types of soil fauna communities were studied.Results of the analysis were collated with traditional Shannon-wiener index,Pielou index and Mackintosh index.Mechanisms of the formation of such patterns were analyzed and explained,taking into account the character-istics of the natural environment of the study zone.The results showed that the log-series and log-normal distribution models fit well the species-abundance distribution of soil fauna communities,displaying a pattern of enriched species being few,and rare species being plentiful,but the broken-stick model could not.All in all,species was positively correlated with abundance and log-series was the best model.Compared with the traditional method of diversity indexes,the species-abundance pattern was more intuitionistic and more vivid in expressing the characters and difference in diversity of soil fauna communities between different parts of the sloping field.