中国主要自然致灾因子的区域分异

A RESEARCH ON REGIONAL DISTRIBUTION OF MAJOR NATURAL HAZARDS IN CHINA

依据１０２种自然致灾因子分布图，以县域为统计单元，建立了全国自然致灾因子数据库。在此基础上，绘制出中国自然致灾因子多度、相对强度、被灾指数图，进而分析了它们的区域分异，为进行中国自然灾害区划提供依据。

According to distribution of 50 types of natural hazards all across the country. this article discusses types. percentage of covered area. as well as relative intensity of all these natural hazards in each county and the statistical units. Besides. we build a data base of 2265 counties all over the country and for 102 types or subtypes of natural hazards. Based on the data base, we produce maps of Distribution of Multiple Degree of Natural Hazards in China. Distribution of Relative intensity of Natural Hazards in China.and Distribution of Covering Index of Natural Hazards in China. We also analyse their regional distribution to support further research on regionalization of natural hazards in China.Three indexes are used in the article to express regional distribution of natural hazards. They are multiple degree. relative intensity and covering index of natural hazards.The article draws the following conclusions:a. Areas with poor natural enviromental conditions or ECOTONE must not have high multiple degree and relative intensity. Natural conditions in Guizhou, the most typical area. are poor. but they are not yet able to become natural hazards.b. Sensative zones of natural environmental evolution must not suffer from both high multiple degree and high relative intensity. For example, semiarid areas in northern China especially the combined area of agriculture and animal husbandry, are multiple hazard areas other than intense hazard areas. while Southwest China is intense hazard area with low multiple degree.c. Northern China has the highest multiple degree, relative intensity and covering index of natural hazards all across the country.d. According to the clear regional distribution of natural hazards in China. nine regions of natural hazards can be divided. which are Northeastern China Region. Northern China Region, combined Region of agricuiture and animal husbandry in Northern China. Northwestern China Region,Qinghai- Xizang Plateau Region, Southwestern China Region. Guizhou Platcau Region. Middle China Region and Coastal China Region.