京津冀都市圈城乡建设用地空间扩张特征分析

The Spatial Expansion of Construction Land-use in Beijing-Tianjin-Hebei Metropolis Circle

本文采用1990、2000、2006年3期多源影像数据、基础地理数据、DEM数据、社会经济统计数据及其他相关资料,采用遥感信息提取GIS空间分析及土地科学相关模型等综合研究方法,首次提取近20多年来京津冀都市圈城乡建设用地的空间信息(误差在10%以内),并分析了城乡建设用地变化的幅度、速度、空间增长格局及其相关性。结果表明,京津冀都市圈城乡建设用地总面积持续增加,1990-2006年,建设用地年平均变化率为2.81%;建设用地年变化速率较大的地区是唐山、保定、石家庄,大于全区平均变化率。京津冀都市圈城镇用地空间增长格局中,70%左右的新增城镇用地分布在城中心40km范围内,80%以上的新增建设用地集中在高速公路沿线20km范围内,并且新增城镇用地呈现沿城市中心、高速公路向外扩张的趋势。城乡建设用地增长具有较为明显的集聚特征。它们为京津冀地区土地利用规划及生态环境研究提供一定的科学数据和决策借鉴。

With the help of remote sensing images （Landsat TM in 1990s and 2000s, Spot4 in 2006）, DEM of 90m spatial resolution, 1 - 50000 topographic maps, socio-economic statistical data and other relevant information, using ENVI 4.7, Arclnfo 9.2 and spatial statistical analysis software （Geoda 095i） and some other research methods such as remote sensing information extraction, spatial analysis method, land-use dynamic changes model and theory, we carry out the research on construction land-use change in Beijing-Tianjin-Hebei Metropolis Circle. Firstly, interpreting remote sensing images and analyzing the changes of urban and rural construction land-use, including the quantity and speed of land-use change, spatial pattern and spatial autocorrelation of land-use growth, the study shows that the urban and rural construction land is expanding continually from 1990 to 2006 with a 2.81% annual increasing rate, the total area of construction land is 11001.81 km2, 13786.14 km2, 15940.55 km2 in 1990, 2000 and 2006 respectively, the relative rate of change in Tangshan, Baoding and Shijia- zhuang are larger than the average rate of the total area in the period from 2000 to 2006. Secondly, discussing the spatial variation of urban construction land by spatial buffer analysis methods, the result shows that the uneven development of spatial expansion including centralized development and ribbon-shaped development is signifi- cant, that is, 70% of the new distribution of urban land is within 40km from the town centre, and 80% of the new construction sites focus on the highway along the 20km range. Comparing the spatial distribution change during the two periods, i.e., new urban land from1990 to 2000 and from 2000 to 2006, we found that the new added urban land presents an expansion trend to outskirts of the city and the highway. Finally, in order to explore spatial aggregation of new added rural-urban construction land further, Global Moran＇ I, Moran scatter plot and LISA spatial aggregation map with statistical unit of the 123 counties in Beijing-Tianjin-Hebei Metropolis Circle were constructed. The results show that the spatial distribution of the rural-urban construction land-use growth is not entirely random, but is spatial clustering with the similar spatial value. Moran＇s I of the additional urban and rural construction land during the two periods were 0.2645 and 0.4067. This study will be helpful for land use planning and ecological researches for Beijing-Tianjin-Hebei Metropolis Circle.