Characterizing urban expansion of Korla City and its spatial-temporal patterns using remote sensing and GIS methods  

作　　者：Bumairiyemu MAIMAITI DING Jianli Zibibula SIMAYI Alimujiang KASIMU 

机构地区：[1]College of Resource and Environment Sciences, Xinjiang University, Urumqi 830046, China [2]Key Laboratory of Oasis Ecology, Xinjiang University, Urumqi 830046, China [3]Key Laboratory of Wisdom City and Environment Modeling of Colleges and Universities, Xinjiang University, Urumqi 830046, China [4]School of Management, Xinjiang Agricultural University, Urumqi 830052, China [5]School of Geographic Science and Tourism, Xinjiang Normal University, Urumqi 830054, China

出　　处：《Journal of Arid Land》2017年第3期458-470,共13页干旱区科学（英文版）

基　　金：funded by the National Natural Science Foundation of China(41161063,41261090,41361043,41661036);the National Natural Science Foundation of China–Xinjiang Mutual Funds(U1603241);the Xinjiang Uygur Autonomous Region Science and Technology Support Project(201591101);the special fund of the Xinjiang Uygur Autonomous Region Key Laboratory(2014KL005,2016D03001);the Open Project Fund of the Key Laboratory of Oasis Ecology of the Education Ministry,Xinjiang University(040079)

摘　　要：Cities provide spatial contexts for populations and economic activities. Determining the spatial-temporal patterns of urban expansion is of particular significance for regional sustainable development. To achieve a better understanding of the spatial-temporal patterns of urban expansion of Korla City, we explore the urban expansion characteristics of Korla City over the period 1995-2015 by employing Landsat TM/ETM＋ images of 1995, 2000, 2005, 2010, and 2015. Urban land use types were classified using the supervised classification method in ENVI 4.5. Urban expansion indices, such as expansion area, expansion proportion, expansion speed, expansion intensity, compactness, and fractal dimension, were calculated. The spatial-temporal patterns and evolution process of the urban expansion （e.g., urban gravity center and its direction of movement） were then quantitatively analyzed. The results indicated that, over the past 25 years, the area and proportion of urban land increased substantially with an average annual growth rate of 15.18%. Farmland and unused land were lost greatly due to the urban expansion. This result might be attributable to the rapid population growth and the dramatic economic development in this area. The city extended to the southeast, and the urban gravity center shifted to the southeast as well by about 2118 m. The degree of urban compactness tended to decrease and the fractal dimension index tended to increase, indicating that the spatial pattern of Korla City was becoming loose, complex, and unstable. This study could provide a scientific reference for the studies on urban expansion of oasis cities in arid land.Cities provide spatial contexts for populations and economic activities. Determining the spatial-temporal patterns of urban expansion is of particular significance for regional sustainable development. To achieve a better understanding of the spatial-temporal patterns of urban expansion of Korla City, we explore the urban expansion characteristics of Korla City over the period 1995-2015 by employing Landsat TM/ETM＋ images of 1995, 2000, 2005, 2010, and 2015. Urban land use types were classified using the supervised classification method in ENVI 4.5. Urban expansion indices, such as expansion area, expansion proportion, expansion speed, expansion intensity, compactness, and fractal dimension, were calculated. The spatial-temporal patterns and evolution process of the urban expansion （e.g., urban gravity center and its direction of movement） were then quantitatively analyzed. The results indicated that, over the past 25 years, the area and proportion of urban land increased substantially with an average annual growth rate of 15.18%. Farmland and unused land were lost greatly due to the urban expansion. This result might be attributable to the rapid population growth and the dramatic economic development in this area. The city extended to the southeast, and the urban gravity center shifted to the southeast as well by about 2118 m. The degree of urban compactness tended to decrease and the fractal dimension index tended to increase, indicating that the spatial pattern of Korla City was becoming loose, complex, and unstable. This study could provide a scientific reference for the studies on urban expansion of oasis cities in arid land.

关 键 词：urban expansion spatial-temporal changes urban land remote sensing and GIS Korla City 

分 类 号：F299.27[经济管理—国民经济] P237[天文地球—摄影测量与遥感] P208[天文地球—测绘科学与技术]