Keshan Disease And Geographical Environment Based On Gis Analysis

Keshan Disease(KSD) is a kind of endemic heart disease. Although it has been becoming less in recent years, the origin of it still has not reached an accurate final conclusion. The incidence of this KSD was very high from 1970s to 1980s in Zhangjiakou of area. At present the research methods of KSD is mainly depending on the traditional epidemiology and geography, This paper uses the method of GIS to analyze the incidence and distribution of KSD and their relationships with the content of selenium in food and human hair, local landforms, climate, hydrography and soil from the point of geography. The study includes special subject cartography, space analysis, DEM analysis and statistics analysis by GIS to explor the regular pattern of the distribution of KSD and it relations with the regular patterns of trace element landforms ( elevation, grade of slope, and direction of slope ), temperature and precipitation, soil and hydrography. A database and KSD GIS system have been set up to search and view the above analyzing results.Results: (1) The distribution of KSD in Zhangjiakou has relations with the landform and climate patterns. It mainly concentrates in the area of altitude from 1480m to 1610m, The average annual temperature 2-4.2℃ and the annual precipitation is above 400mm; (2) The concentrations of selenium in geo-ecosystem in Zhangjiakou area are also have relations with the patterns of landform.The area in which the content of the hair selenium and food selenium is lower mainly distributes in the altitude from 1580m to 1650m and from 1660m to 1780m and in the area with grade of slope from 2.97 to 4.78 in southward;(3)Selenium concentration in human hair in Zhangjiakou area has positive correlation with that in grains,which show a similar distribution tendency of the incidence of KSD.Under the support of GIS and statistics, based on the endemiologye and geography theories,this study inquires into the dynamic and mutual effects of many factors and their space distribution in connections with KSD in Zhangjiakou.The introducing of GIS DEM and space analysis expands the traditional endemiology analysis methods of KSD .It not only can quantitatively analyse KSD easy, but also can visually show the data in form of maps/figures.Therefore, this paper offers a method of GIS into KSD research, carries out analysis with the aid of statistics which supplies an example for research of the other endemicdiseases.