基于GIS 的中国人居环境指数模型的建立与应用

以1km×1km栅格为基本单元,选取地形、气候、水文、植被等自然因子,构建了基于人居环境指数的中国人居环境自然适宜性评价模型,运用GIS技术,定量评价了中国不同地区的人居环境自然适宜性,揭示了中国人居环境的自然格局与地域特征。研究表明:中国人居环境指数整体呈现由东南沿海向西北内陆递减的趋势;人居环境指数与人口密度显著相关,二者的对数曲线拟合度R2值高达0.87,人居环境指数可以综合反映区域人居环境的自然适宜程度。中国人居环境自然适宜性评价结果显示,中国人居环境适宜地区430.47×104km2,接近国土面积的45%,相应人口占全国的96.56%,其中3/4以上的人口集聚在约占1/4人居环境高度适宜和比较适宜地区;中国人居环境临界适宜地区225.11×104km2,占国土面积的23.45%,相应人口4112万,占全国的3.24%,人口密度每平方公里18人,是中国人居环境适宜与否的过渡地区;中国人居环境不适宜地区304.42×104km2,人口249万,不到全国的0.2%,人口密度每平方公里不足1人,大片地区沦为"无人区"。

Establishment and Application of Human Settlements Environment Index Model (HEI) Based on GIS

With the degeneration of environment and acceleration of urbanization, human settlements have attracted great attention worldwide. For the necessity of natural environment evaluation of human settlements, by choosing terrain, land cover, climate and water condition as the evaluation factors, based on Geographic Information System technique, this paper sets up the human settlements environment index (HEI) model and evaluates the natural environment suitability of human settlements in China with it. The results show that: the HEI of China decreases from southeast to northwest in general, which reflects the regional difference of natural environment suitability of human settlements in China; and HEI is significantly correlated with population density at grid size and the R2 value for them amounts to 0.87, which indicates that natural environment suitability of human settlements has a significant influence on population distribution. From southeast to northwest and from hilly regions and plains to plateaus and mountainous areas, the natural environment suitability of human settlements in China decreases in general. Specifically, the high suitable region, with a land area of 95.92×10⁴ km² and a population of 380 million, is mainly located in Southeast Hilly Region and most parts of the middle and lower reaches of the Yangtze River; most parts of Yunnan-Guizhou Plateau and Sichuan Basin, Guanzhong Basin and southern part of North China Plain belong to the moderate suitable region, accounting for 1/6 of a land area and one half of population of China; with a land area of 167.78×10⁴ km² and a population of 226 million, the low suitable region mainly includes Northeast China Plain, northern part of North China Plain and Loess Plateau; eastern part of Tibetan Plateau, Junggar Basin and Inner Mongolia Plateau belong to the critical suitable region, covering a land area of 225.11×10⁴ km², and 41 million people live in this region; and the non-suitable region mainly includes most parts of Tibetan Plateau, Tarim Basin and Alex Plateau, where the land area is 304.42 km², but there are only 2.49 million people. From the high suitable to the non-suitable region, the land area increases with the decrease of population density, indicating that the population in China is mainly concentrated in natural environment suitable region.