关键词: 三带喙库蚊, 孳生状态, 分布型, 聚集分布

Abstract: Culex tritaeniornynchus is one of the species breeding in the paddy fields, and an important vector of Japanese B encephalitis in China. This paper dealt with the spatial distribution patterns of C. tritaeniorhynchus larvae in the rice fields. All study was undertaken in Lishui county, Zhejiang province from 1988～1990.Density of mosquito larvae was surveyed in 9 plots of rice fields, It was proved that the distribution of C. tritaeriorhynchus Iarvae in paddy fields was mostly in aggregated pattern and was goodness-of-fit for agreement with neagative binomial distribution. Both values of K and C are>0; application of Iwao's model of them^* -m method to the analysis of spatial pattern, a>0, β>1. It indicates that C. tritaeniorhynchus larvae fit aggreation distribution in the form of colony in paddy fields.The coefficient of variation(C. V) between peripheral part and central part of rice field are 137. 79-248. 56% respectively. Comparison of the mean densities between these two parts (2.1821: 1.6982)u=3.01, p<0.01. This showed a significant difterence. The densities of larvae also showed different positions was remarkable difference, the mean density of larvae was lower in Northern positions