The expansion of construction land is the direct evidence of human transformation of the earth's surface.Lanzhou-Xining Urban Agglomeration was selected as the study case in this paper,which has an important and fragile ecological environment in the upper reaches of the Yellow River.Based on four periods of high-resolution remote sensing image data,the expansion intensity index and standard deviation ellipse were used to study the spatio-temporal characteristics of construction land expansion from the perspective of"multi-scale and multi type".The results show that:(1)the construction land of Lanzhou-Xining Urban Agglomeration continues to expand,and the expansion of urban construction land in Qinghai Province and Gansu Province,Lanzhou city and Xining city has the characteristics of"co-directional centrifugation",while that in Xining city and Haidong city has the characteristics of"co-frequency resonance",and the urban construction land expansion of counties(dis-tricts)presents a"core-edge"model.(2)Rural residential land began to increase slowly after 2010,showing the expansion characteristics of"rapid recession in urban areas,slow expansion in suburban areas,and stable or slow decline in agricultural and pastoral areas".(3)Other construction land is increasing,showing a spatial differentiation characteristic of"rapid expansion in the east and west,slow expansion in the north,and stable and unchanged in the south".The research results can provide references for the optimization of land spatial layout in Lanzhou-Xining Urban Agglomeration and national differential allocation of construction land indicators.
关键词
建设用地扩张/时空特征/遥感数据/标准差椭圆/兰西城市群
Key words
construction land expansion/spatio-temporal characteristics/remote sensing data/standard deviation ellipse/Lanzhou-Xining Urban Agglomeration
万方数据