基于多源遥感数据的陕西2000～2015年城市扩展研究

Study on Urban Expansion in Shaanxi Province from 2000 to 2015 based on Multi-source Remote Sensing Data

夜间灯光数据已成为监测城市发展进程及空间格局演变的重要依据。利用覆盖陕西省的2000、2005、2010年3期DMSP/OLS数据及2015年无云复合NPP/VIIRS数据,结合MODIS等多源遥感数据构建VANUI、EANTLI两种指数模型,识别并提取陕西省城市建成区面积,经过对比分析后,选取较为精确的EANTLI指数重建陕西省2000～2015年城市扩展进程,并对西安市城市扩展的细节特征进行探究。结果表明:EANTLI指数在城市建成区识别与提取方面较VANUI指数稳定;2000～2015年陕西省城市扩展的不均衡性较为突出,关中各地市城市建成区面积增长速率最快,陕北次之,陕南地区较为缓慢。陕西省城市扩展的主要特征是以各地市中心城市为核心,呈同心圆或扇形模式向外蔓延;西安市城市扩展具有明显的外延性特征,城市重心逐渐向西移动,城市建成区向西北、西南方向持续扩展。

Night lighting data has become an important tool for monitoring urban development process and spatial pattern evolution.Three issues of DMSP/OLS data covering Shaanxi Province in 2000,2005,2010 and annual cloudless composite NPP/VIIRS data of 2015 were used.Combined with other multi-source remote sensing data,two index models of VANUI and EANTLI were constructed to identify and extract the area of urban built-up area in Shaanxi Province.Select the more accurate EANTLI index to rebuild Shaanxi Province 20002015 urban expansion process,and explore the details of Xi’an urban expansion characteristics.The results show that.In 2000 and 2015,the area of urban built-up area in Shaanxi Province increased by 159%,and there were obvious differences among different cities:the growth rate of urban built-up area in Guanzhong region was the fastest,followed by Northern Shaanxi.The area of southern Shaanxi is relatively slow;The urban expansion of Xi’an city has obvious stage characteristics,the center of gravity moves westward gradually,the urban built-up area gradually expands to the northwest,and the southwestern direction continues to expand.