基于栅格数据的陕西省人居环境自然适宜性测评

Evaluation of Nature Suitability for Human Settlement in Shaanxi Province Based on Grid Data

人居环境中的自然基础和生态背景,不仅直接关系到人的身心健康和生活质量,而且影响人类发展水平与社会进步。科学度量人居环境自然适宜性空间格局,对于界定主体功能区、引导人口合理分布与流动,促进人口与资源环境协调发展具有重要意义。运用GIS技术,采用综合指数法,基于陕西省96个气象站点1966-2005年气象数据、1990-2007年逐月NDVI和LandsatTM影像、1:25万DEM、2000年陕西省人口详查数据、2006人口数据以及其他相关资料,以100m×100m栅格单元构建并直观展现了陕西省人居环境自然适宜程度空间格局,在此基础上,剖析了各区的适宜性和限制性因子。结果表明:陕西省的人居环境指数介于18.55～88.97之间;从西北向东南、从山地、高原向平原、河谷人居自然适宜程度递增。一般适宜区面积最广,占陕西省总面积的63.28%;比较适宜地区居次,占26.11%;临界适宜区占10.26%;高度适宜区面积最小,仅占0.35%。陕西省总人口的68.92%分布在占全省面积26.46%的高度适宜区和比较适宜区。地表水资源和地形起伏度是引起省内人居环境自然适宜性分异的主要因子。实证分析表明该测评结果比较客观地反映了陕西省人居的自然生态背景。

Scientifically evaluating natural suitability for human settlement and defining function zones of population development will promote coordinated regional development between population, resources and environment. In this paper, Geographic Information System （GIS）, integrated index analysis, correlation analysis and demonstration were employed to establish the spatial situation of nature suitability for human settlement in Shaanxi Province. Results showed that： the index of nature suitability for human settlement in Shaanxi Province was between 18.55 and 88.97. In general, nature suitability for human settlement increased from northwest to southeast and from mountain and plateau to plain and valley. Considering area, the common suitable region ranked first, accounting for about 63.28% of the total area of Shaanxi Province; and rather and comparatively suitable region ranked second, about 26.11% of the total; and the most desirable region ranked last, only about 0.35%. On the other hand the population of the province was concentrated in regions with higher nature suitability. About 68.92% of Shaanxi＇s population was concentrated in the most desirable region and rather and comparatively suitable region. Nearly 88.16% of Shaanxi＇s population was distributed in grade one of common suitable region and above that level. Spatial distribution of population was profoundly affected by nature suitability for human settlement in Shaanxi Province. Regions with maximal population density always were the ones with highest nature suitability for human settlement. The influence of span of climate suitability on spatial distribution of population was partly in Shaanxi Province. Surface water shortage was the bottleneck of nature suitability for human settlement in northern Shaanxi and northern Guanzhong, while high altitudes and wavy terrains were the bottleneck of nature suitability for human settlement in the Qinling-Daba mountains and Loess Plateau. Lack of water and sparse vegetation were the main natural restriction to human suitability in wind-eroded areas of northern Shaanxi.