Objective To study the distribution of Oncomelania hupensis in marshland and lake regions in order to provide the knowledge for Oncomelania hupensis ecology.
Conclusions The distribution of Oncomelania hupensis in marshland and lake regions is not simply negative binomial distribution, but probably a dynamic process.
The other districts were considered as control districts,one with niclosamide 2? g/m\+2,another with no drug. Results In marshland area,within 30days the snail death r ates in two trial districts ranged from 18.21% to 40 38% and from 31.65% to 36. 0 7%,respectively significantly lower than that in niclosamide district;
In 1998,the flooding year,the area of snail increased 4.97% in the disaster region in Anhui province. The area of snail increased by 55.44% in hilly endemic area that was most remarkably in different endemic type region,but the absolute area increased in the marshland region was the main part in the flooding year that accounted for 59.06%.
Samples have been collected from core sections recovered by drilling 60 to 70 km apart from each other in western and eastern areas of the Onega Lake region.