应用地理信息系统分析洲滩钉螺的分布

THE APPLICATION OF GEOGRAPHICAL INFORMATION SYSTEM FOR ANALYSIS OF SNAIL DISTRIBUTION

本文应用地理信息系统（GeographicalInformationSystem，GIS）探讨洲滩钉螺分布与水位的关系。根据活螺密度和感染螺密度，用Ward法将洲滩聚为四类，各类螺情有明显不同。洲滩的全年淹水天数对密螺带的作用在不同的水年有明显差别；同一水年内，将Ⅰ、Ⅱ、Ⅲ类洲滩合并后与Ⅳ类洲滩进行全年淹水天数比较亦有显著差异，提示全年淹水天数在钉螺分布中的重要作用。星子县病情图和洲滩螺情图在GIS中的重叠，直观显示了螺情和病情的一致性，提示GIS在血吸虫病研究中有一定潜力。

A Geographical Information System (GlS) is applied in studying the relationship between water level and snail distribution ln marshlands. Based on the density of alive snail and infectious snail,a ward method was used to cluster the marshlands into four categories which have different snail distribution, The influence of the drowning days for the whole year on the concentrated snail belt of marshlands varied with different water year. In the same water year,the comparison of the drowning days for the whole year between marshland Ⅳ and thecombination of marshland Ⅰ, Ⅱ, Ⅲ showed to be statistically significant. The results impliedthe important role of the drowning days for the whole year in the snail distribution. The overlapping of acute schistosomlasis map of Xinzi and snail map of marshlands displayed the consistent distribution in an audio-visual way. GIS has a potential in schistosomiasis research.