Abstract: Objective To explore the spatial pattern of the distribution of Oncomelania hupensis population in marshland and lake region. Methods Four bottomlands were selected randomly for the investigation along the Qiupu River in Guichi District, Anhui Province. The quadrats were placed randomly for snail survey, and the mean crowding, mean density, aggregation indices (diffusion coefficient(C), morisita index(I_δ), index of patchiness(m*/m) ), Taylor’s power law and Iwao’s m*-m regression index were analyzed. Results For 4 bottomlands in different time, the diffusion coefficients, Morisita indices, and m*/m indices were all more than one. There was a close linear relationship between the logarithm of the snail density and its variance (P＜0.01), and the correlation coefficient was 0.972. In Taylor’s power law, the lg a was 0.602 and b was 1.427. There was a close linear relationship between the mean crowding(m*) and the snail density(m) (P＜0.01), and the correlation coefficient, α and β was 0.984, 2.367 and 1.617 respectively. Conclusion The spatial pattern of Oncomelania hupensis population shows an aggregation distribution in marshland and lake region, and the basic components of snail distribution are in colonies.

Key words: Oncomelania hupensis, Population ecology, Spatial pattern, Marshland