关键词: 个体大小, 农田, 生长, 标志重捕, 种群密度, 大足鼠

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