基于RS/GIS的广西流行性乙型脑炎的环境因素研究

A RS / GIS-based study on the environmental factors of Japanese encephalitis in Guangxi

目的运用RS/GIS技术探索性研究影响广西壮族自治区(简称广西)流行性乙型脑炎(简称乙脑)流行的环境因素,为广西乙脑的区域性生态防控提供科学依据。方法收集2004年广西各市县乙脑的病例数据、人口数、归一化植被指数、地表温度、土地利用类型和高程等资料,利用反距离加权插值和Spearman相关分析研究生态因素与乙脑发病率的关系。结果 Spearman相关分析显示:归一化植被指数、平均高程、林地构成比与乙脑发病率存在正相关关系,差异均有统计学意义(均有P<0.05);而地表温度、耕地面积构成比、建筑用地构成比与乙脑的发病率存在负相关关系,差异均有统计学意义(均有P<0.05);尚不能认为草地构成比、水域构成比和未利用土地构成比与乙脑的发生有关。反距离加权插值图显示乙脑发病率与环境因素在空间上具有一定的分布一致性。结论广西乙脑流行的空间格局与多种环境因素有关。通过RS/GIS技术可以提取和分析乙脑相关的环境因素,进而实现乙脑的生态监测,这是对乙脑流行趋势进行早期预测的有效途径。

Objective To identify environmental factors of Japanese encephalitis （JE） based on RS/GIS te- chiniques. Methods Nnormalized difference vegetation index, surface temperature, land farming and altitude were ob- tained from MODIS Image. Subsequently, inverse distance weighted and spearman~ correlation were employed to analyze the association between JE and environmental factors. Results Normalized difference vegetation index, average altitude and forestland were positively correlated with JE. However, land surface temperature, cropland, building land were nega- tively associated with JE. There was no significant correlations among grassland, water body, unfarmed land and JE. Con- clusions JE is related to environmental factors, RS/GIS techniques should be applied to extract environmental factors from remote image. Furthermore, to some extent, the spatial pattern of JE was consistent with spatial pattern of environmental factos.