Urban Expansion of China from the 1970s to 2020 Based on Remote Sensing Technology

• 作者: LIU Fang ZHANG Zengxiang ZHAO Xiaoli LIU Bin WANG Xiao YI Ling ZUO Lijun XU Jinyong HU Shunguang SUN Feifei WANG Yafei
• 来源期刊: 中国地理科学（英文版）
• 年，卷（期）: 2021,（5）
• 页码范围: 765-781
• 页数: 17页
• 语种: 英文

摘要

Based on Remote Sensing (RS) and Geographical Information System (GIS) technology,urban expansion of 75 cities in China from the 1970s to 2020 was reconstructed by visual-interpretation method,which described the growing process of urban lands and its influences on local land use structures synchronously.By employing annual expansion area per city and urban expansion density,spatial-temporal characteristics and macro patterns of urban expansion were analyzed from the aspects of regional-distributions,admin-istrative-levels and population-sizes comprehensively.Results indicate that:1) urban expansion in China was universal,distinct,persist-ent,periodic and fluctuating.In the past five decades,urban lands of 75 monitored cities in China expanded dramatically from 3606.26 km2 to 30521.13 km2.2) Though urban expansion presented significant differences from the aspects of regional distribution,administrative levels,and population sizes,it exhibited a deceleration trend in the 13th Five-Year Plan among all kinds of cities.3) Cul-tivated lands were the first land resource for urban expansion,and 55.17％ of newly-expanded urban lands appeared by encroaching this land use type.China's urban expansion has caused sustained pressure on cultivated land protection,especially in super megacities,and the contradiction between urban expansion and cultivated land protection will always exist.4) The compactness of urban lands in China increased before 1987 and reduced in the next three decades,which was consistent with the implementation of major policies and the de-ployment of national strategies,and is expected to become compact with a stopping declining or even rebounding after the 13th Five-Year Plan.