Abstract: Mark-recapture，trap-dissection and captive fee,dins methods provided data on population density，body size-growth and biornass for a population of Mark-recapture，trap-dissection and captive fee,dins methods provided data on population density，body size-growth and biornassfor a population of rattus nitidus in the Western Sichuan Plain from January 1989 tbrough June 1995．With highest 11．3 individuals／ha and lowest 0.7 Indjviduah／ha．population density showed the Same seasonal fluctuations patterns as crops and averaged 3.5 individuals／ha．Sex ratio of males to females decreased from 1 :1 of juveniles and subadults to 1:0.78 of adults to 1:0.53 of elders.Body mass of males and females averaged，respectively,l36 and114g，and showed apparent sex dimorphism in body mass，and hind-foot length as well-,but not in body length or ear length.Body mass and tail length ofjuvenile and subadults keptgrowing during study period can be fitted adequately by logistic and power equations, respectively． Biomass was more stable than population density and mean body mass .

Key words: Body size, crop field, Growth, Mark_recapture, population, density, rattus nitidus

摘要： 我们利用标志重辅、夹辅解剖和笼养等三种方法于1989年1月至1995年6月对川西平原的大足鼠的种群密度，个体大小、生长和生物量进行了研究。种群密度最高11.3只/ha，最低0.72只/ha，平均3.6只/ha，并显示出与农作物相同的季节变动特征。雌雄性比由幼年组和亚成体组约1：1到成体组1：0.78到老年组1：0.53。雌雄个体的平均质量分别为0.136㎏和0.114㎏，两性的个体质量和后足长有明显差异，体长和耳长差异不明显。船 雌雄十体的平均质量分别为J 06 g和I14 g，两性的个体质量和后足长有明显差异，饲养的幼体及亚成体个体质量和尾长均持续增长，并可分别用Logistic和对数方程较好地拟合。生物量则显示出比种群密度和十体质量更稳定的特征。

关键词: 个体大小, 农田, 生长, 标志重捕, 种群密度, 大足鼠