关键词: 大足鼠, 农田, 种群, 试验, 啮齿动物, 群落

Abstract: During 1993 ～1995 we conducted an experiment in which we removed the dominant species of rodent, Rattus nitidus, from a 2 hm² plot in theWestern Sichuan Plain and set a 1.5hm² control plotin the same habitat. The experiment evaluates the extent to which the dominant species influences other rodent populations. Monito ring with live traps and statistical analyzing with paired t-testing of difference between the experimental and control plots revealed that: the removal of R.nitidus (1) resulted in increases of population density (R.nevigicus and R. flevipectus) and biomass (R.confucians) during a certain year o r overall study period;(2) induced significant increases in the number of species and Shannon indexes of species diversity during 1995 and overall study period; (3) resulted in no significant changes in joint population density, biomass, evenness of species. These results indicate that occurrence of the dominant species plays a major role in regulating the number of species and determining the organization of crop land rodent communities. Competition between the dominant species and other rodent populations for resources was limiting the number of species in the community.But we have not identified which components in resources were working in limiting the species number and species diversity by our relative simple experimental manipulations.

Key words: Community, Crop land, Experiment, Population, Rattus nitidus, Rodent