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

摘要： 为了研究农田啮齿动物群落的动态规律，用标志重捕的方法给出了川西平原农田的啮齿动物群落的物种数、结合种群密度、生物量、物种多样性的Shanon 指数与Simpson指数等5个变量的时间序列资料，并分析了这些时间序列的年间变动和季节变动的特点。结果表明：（1）5个变量总是处于不断的变化之中，特别是年间交替升降十分明显；（2）群落的全部8个物种从未同时出现过，同一个月最多有5个物种，最少只有1个物种；（3）5个变量季节变动的幅度均较大并各具有1至3个不等的明显的峰值，而年间变动的幅度则相对较小；（4）5个变量的最大值均出现在夏季，最小值则出现在春季、夏季或冬季；（5）5个变量的季节性均不强；（6）优势种大足鼠（Rattus nitidus）的种群密度分别与群落结合种群密度、生物量的年间变动和季节变动均具有相似的变动规律；此外，优势种大足鼠的种群密度、生物量分别占群落结合种群密度、生物量的比例均较高，而且这两个比例季节变动的幅度都较大而年间变动则较为稳定。

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