Prediction of Oncomelania Hupensis Distribution Based on Remote Sensing and Spatial Analysis Technology in Dongting Lake Region of China

The amphibious snail Oncomelania hupensis(O. hupensis) is the only intermediate host of Schistosomiasis japonica, which is a parasitic disease of considerable public health and economic significance. The survival of O. hupensis is governed by climatic and environmental factors, including vegetation, temperature, soil type and water level, etc. In this study, the environmental factors were derived from Landsat TM remote sensing image, and the relationship between environmental factors and the density of O. hupensis was analyzed by a multiple linear regression model. Although stepwise regression demonstrated that O. hupensis densities of live snails related significantly to the modified soil adjusted vegetation index (MSAVI), wetness index and land surface temperature (LST), the low correlation coefficient (0.3619) indicated that some important factors related to the abundance of snail had not yet been taken into account in the multiple linear regression model. Then, the great spatial analysis of the Geographic Information System (GIS) was used as a new tool to study the relationship between the distribution of O. hupensis and the surveillance of O. hupensis habitas. Spatial analysis of the regression residual was investigated by the semi-variogram method, and the spatial variation of O. hupensis density attributed to the spatial autocorrelation was estimated by ordinary kriging. Therefore, remote sensing and spatial analysis were both employed to predict the distribution of O. hupensis. Following this approach, O. hupensis in Dongting Lake region, China was predicted and the prediction results are validated with field data. The prediction results indeed improved considerably.