A study of environmental changes on new snail habitat though multi-temporal relative radiometric normalized TM images / 中华预防医学杂志

<p><b>OBJECTIVE</b>To study the environmental changes of new snail habitual by using multi-temporal relative radiometric normalized TM images taken in Wuzhoutou of Nanchang, Jiangxi province.</p><p><b>METHODS</b>TM images of Poyang Lake were collected on 3rd April 1998, 16th April 2000 and 5th May 2004. Taking images in 2004 as a reference, the TM images in 1998 and 2000 were radiometric normalized. The images were analyzed to trace the vegetation background and snail historical information.</p><p><b>RESULTS</b>The vegetation coverage rate of Wuzhaoutou on April 3rd in 1998 was 4.76%, but the vegetation coverage rates of Wuzhoutou on April 16th in 2000 and May 5th in 2004 were above 80%; the NDVI values of Wuzhoutou on April 3rd in 1998 were around -0.4 to 0.2, but the NDVI values of Wuzhoutou on April 16th in 2000 and May 5th in 2004 were mainly around 0.2 to 0.6, which had statistical difference with that in 1998 (q = 162.285321, P < 0.01 and q = 161.669725, P < 0.01). The greenness of three images have statistical differences(q = 178.679245, P < 0.01; q = 130.320755, P < 0.01 and q = - 48.358491, P < 0.01).</p><p><b>CONCLUSION</b>Combining with the snail survey, the TM images could be an effective measure for setting up models to forecast the areas where snails might live to control the Schistosomiasis epidemic.</p>

Application of global positioning system and geographic information system in surveillance of schistosomiasis / 中华预防医学杂志

<p><b>OBJECTIVE</b>To use the snail survey data of Yugan, Jiangxi Province as an example to evaluate the effects and advantages of global positioning system integrated with digital maps and remote sensing data in order to manage and analyze the whole country's surveillance data of schistosomiasis by using geographic information system.</p><p><b>METHODS</b>The data of geographic information and snail information of 20 marshlands in Yugan, Jiangxi Province were collected, and by the correction of remote sensing images based on the digital maps and index extraction, the snail current situation and trend were analyzed and expressed.</p><p><b>RESULTS</b>A series of specific procedure images of these 20 marshlands was established and the effects of Yugan surveillance platform based on geographic information system were validated.</p><p><b>CONCLUSION</b>The whole country's surveillance data of schistosomiasis might be successfully integrated with geographic information system by global positioning system and be managed and expressed, which supplies a successful platform in using the surveillance data effectively.</p>