基于缓冲区分析的城市化与地表水质关系研究——以烟台沿海区县为例

将城市化过程中的人为土地定义为建设用地,利用2004年TM影像得到烟台沿海区县建设用地数据。用缓冲区分析提取乡镇水平上建设用地比率和人口密度数据,缓冲半径从100m到2000m,利用ArcView空间分析功能对建设用地比率、人口密度、河网等级和水质进行叠置分析,并结合逐步回归分析方法揭示烟台沿海区县28个水质监测站各水质参量的空间变化情况。结果显示,通过建设用地比率和人口密度共同作用可以解释85%以上的水质参量模型,反映城市化的建设用地比率比人口密度能更好地解释水质参量的空间变化,大多数水质参量的最佳模型出现在2000m的缓冲半径上,表明建设用地比率和人口密度是影响研究区域水质的首要因素。同时,运用缓冲区分析等GIS空间分析方法为区域城市化进程与水环境质量的研究提供了新的途径。

A study on the relationship between urbanization and surface water quality based on GIS technique-a case study of coastal counties in Yantai

In this paper, the artificial land in the urbanization process was defined as the construction land.The construction land data of Yantai coastal counties was obtained from remote sensing TM imageries in 2004.The ratio of construction land and population density in the county level were extracted by buffer zones analysis with radius ranging from 100 m to 2 000 m.The superposition analysis for construction land ratio, population density, waterways rank and water quality was done through the ArcView spatial analysis function.Meanwhile, the spatial variation situation of water quality parameters of 28 water quality monitoring stations in Yantai coastal counties was also discussed with stepwise regression method.The results showed that the construction land ratio together with population density might explain over 85% water quality parameters model.The construction land ratio representing the urbanization level was better than population density in explaining spatial patterns of water quality parameters and the best models of most water quality parameters were found for buffer zones of 2000m radius,which indicated that the construction land ratio and the population density were the prime factors influencing water quality in the study area.It also suggested that the spatial analysis technology based on GIS, such as buffer and superposition analysis, provided a new way to study the relationship between region urbanization process and water environment quality.