干旱内陆河流域人居环境适宜性评价——以石羊河流域为例

论文以干旱区内陆河石羊河流域为研究区,选取坡度、 坡向、 地形起伏度、 植被指数、 水文、 气候、 交通等因子作为评价指标,建立了人居环境指数(HEI),利用GIS的叠置分析、 缓冲区分析、 密度分析等空间分析技术对石羊河流域人居环境适宜性进行了定量综合评价分析。评价结果表明,石羊河流域人居环境指数介于17.13~84.32之间,整体分布格局为:从西南方向到东北方向适宜性依次降低,适宜、 较适宜居住区主要分布在中游和中下游地区,不适宜人类居住区占研究区面积的比例很大。石羊河流域人居环境适宜区主要以带状和斑块状分布在石羊河各支流周围,其他区域只有零星分布,与流域内居民点分布的空间格局相吻合。石羊河流域人居环境状况与人口密度呈对数关系,确定系数达到0.851 2,与经济发展水平呈现较明显的正相关性,人居环境评价值与单位面积GDP确定系数达到0.845 4,与道路网密度关系不显著,受道路制约程度较小。一些居民点分布在人居环境恶劣区域,一些村镇分布在靠近沙漠区域内,地形复杂,气候多变,水资源短缺,经济发展滞后,结合新农村建设规划和当地土地利用规划,这部分村落需要异地搬迁以便改善人居环境状况。

Study on the Suitability Evaluation of the Human Settlements Environment in Arid Inland River Basin——A Case Study on the Shiyang River Basin

The paper selects slope, aspect, relief degree of land surface, vegetation index, hydrology, transportation and climate as evaluation indexes and sets up the Human Settlements Environment Index (HEI) model to evaluate the environment suitability for human settlements in Shiyang River Basin. Through using spatial analysis technique of GIS such as spatial overlay analysis, buffer analysis and density analysis to establish the spatial situation of nature suitability and spatial pattern for human settlement. The results showed that: the index of nature suitability for human settlement in the Shiyang River Basin was between 17.13 and 84.32. In general, nature suitability for human settlement decreased from southwest to northeast. Considering area, the suitable region was mainly distributed in Minqin oasis, Wuwei oasis and Changning basin, which accounted for about 1080.01 km², 2.59% of the total area. Comparatively suitable region was mainly distributed around the county in Gulang, Yongchang and north of Tianzhu County, which accounted for about 1100.30 km². The common suitable region was mainly distributed outside of the county in Yongchang, Jinchuan and most part of Minqin county, which accounted for about 23328.04 km², 56.08% of the total area. The non-suitable region was mainly distributed upstream and north of the river, which accounted for about 9937.60 km², 23.89% of the total area. Meanwhile, the most non-suitable region was distributed around the Qilian Mountain which covered by snow and cold desert and the intersecting area between Tengger Desert and Badain Jaran Desert. The total area was about 6154.05 km², which accounted for 14.79% of the total area. Suitable regions for human inhabitance were distributed mainly around rivers in the form of ribbons and batches, while others are scattered. Their distribution was identical with the residential spatial pattern. There was a clear logarithm correlation between situation of residential environment and population, that is, the coefficient of determination between evaluation value of residential environment and population density reached 0.851 2. There was also positive correlation between situation of residential environment and economics, which reached 0.845 4 between evaluation value of residential environment and GDP. Result also shows the environment is difficult to support the existing population in the Shiyang River Basin. Spatial distribution of population was profoundly affected by severe environment such as the expanded deserts, the wavy terrains, and the changeful climate. Surface water shortage and slow economic growth was the bottleneck of nature suitability for human settlement in the Shiyang River Basin. So according to these problems and various planning, some of the residential parts need to relocate in order to improve situation of residential environment.