岳阳市洞庭湖区洲滩地貌类型与钉螺密度的空间相关性分析

Analysis on spatial correlation between snail density and types of marshland geomorphology in Dongting Lake region of Yueyang City

目的探讨岳阳市洞庭湖区洲滩地貌类型与钉螺密度之间的空间相关性。方法采用Arc GIS 10.2软件,按照地貌特征对岳阳市洞庭湖区的洲滩进行分类,并生成由2 440个六边形组成的洲滩类型格网系统。收集2010-2014年岳阳市28个血防站的洲滩查螺数据,生成活螺、感染螺平均密度的六边形格网系统。对洲滩类型格网系统与活螺、感染螺平均密度格网系统进行相关性分析,探索洲滩地貌与钉螺密度之间的空间关系。结果岳阳市洞庭湖区洲滩可按地貌类型分为9类。其中,凹陷型洲滩的活螺、感染螺平均密度的平均值分别达到9.62只/0.11m^2和3.66只/0.11m^2,为最高水平;带外堤洲滩、岛型洲滩次之;河口洲滩、一般洲滩、窄型洲滩、宽型洲滩居中,而隆起型洲滩、带林洲滩的钉螺平均密度相对较低。结论洲滩地貌类型与钉螺密度具有空间相关性。如能以工程措施对凹陷型洲滩、带外堤洲滩的地貌加以改变,则可有效降低区域钉螺密度。

Objective To discuss the spatial correlation between the classification of marshland geomorphology and snail density in Dongting Lake region of Yueyang city. Methods By using ArcGIS 10. 2 Software, the paper classified the marshlands in Dongting Lake region of Yueyang city according to the topographical features, and generated a marshland type grid system consisting of 2 440 hexagons. By using the marshland snail survey data which was collected from 28 schis- tosomiasis protection and control stations of Yueyang City during 2010- 2014, it established the hexagonal grid systems of living snails and infected snails. Processing a spatial correlation analysis between the marshland type grid system and the living snails and infected snails grid systems, the correlation between marshland geomorphology and snail density can be ex- plored. Results The marshland in Dongting Lake region of Yueyang city could be divided into nine types. Among them, the average densities of living snails and infected snails in the pitting marshland were respectively 9. 62 number/0. 11 m2 and 3.66 number/0. 1 l mR , as the highest type. The marshland with outside levee and the island marshland took the sec- ond place. The estuary marshland, common marshland, narrow marshland and wide marshland were in the middle. The up- lift marshland and marshland with forest had the relatively low snail densities. Conclusions The types of marshland geo- morphology and the snail density have a significant spatial correlation. If some engineering measures can be adopted to change the geomorphology of pitting marshland and marshland with outside levee, the regional snail density might be de- creased remarkably.