关键词: 川西平原, 啮齿动物, 群落动态, 物种数, 生物量, 物种多样性

Abstract: The time series of the 5 variables,including number of species, joint population density, biomass, Shannon index and Simpson index of species diversity of the rodent community, which was composed of 487 individuals of 8 species of 4 genera of Muridae in cropland of the Western Sichuan Plain from 1989 through 1995 are presented for studying the dynamics of the rodent community in the cropland by mark-recapture. Then, both interannual and seasonal fluctuations of the time series of these variables are analyzed and compared. Finally, dynamics of the rodent community in the 7 years are smmarized. The rodent community was concluded as the following: 1) all of the 5 variables fluctuated interannually and seasonally during the 7 years; 2) all of the 8 species of rodents never occurred in the rodent community in the same month with the maximum of number of species 5 and the minimum 1; 3) the seasonal fluctuations of the 5 variables were greater than their interannual fluctuations, respectively, peaked from 1 to 3 in a year; 4) each of the 5 variables had its maximum only in some summers during the 7 years but had its minimum in some winters or springs and sometimes even in some summers; 5) none of the 5 variables showed remarkable seasonality; 6) the seasonal fluctuations of the proportions of the population density and biomass of the dominant species (Rattus nitidus) respectively in the joint population density and biomass of the rodent community were greater than its interannual fluctuations, and both the interannual and seasonal fluctuations of the population density of the dominant species (Rattus nitidus) were much similar to those of joint population density and biomass of the rodent community.

Key words: Western Sichuan Plain, Rodent, Community dynamics, Number of species, Biomass, Species diversity