Author Description

Comparing to the central and east coastal regions of the country, China's northwest is less developed. However, land use and land cover (LULC) changes in this region are also worthy of study because of its resource scarcity and thus its sustainability. The objective of this study was to analyze the LULC changes in Zhangye City over the past 17 years and determine the major drivers of these changes, by integrating remote sensing derived land use/cover information with socio-economic analyses. The Landsat imagery was processed for every two years from 2001 to 2017 in Google Earth Engine environment, and then classified into land use and land cover maps using the random forest classification method. To improve accuracy, NDVI, NDWI, DEM and GLCM were incorporated in the classification. These LULC maps were then used in change detection analysis to quantify the rate of urban expansion and land use changes. The resulting land use change matrices were then used in logistic regression model to determine key socio-economic factors. The correlations between LULC changes and published policies were further analyzed to understand policy implications. The results confirmed the following: a) The Zhangye city went through a dramatic land use change from 2001 to 2017; b) Its urban built-up, water surface, cropland, grassland and forest areas all increased at the cost of surrounding bare lands; and c) The city planning and national government's five-year plan were the main drivers of urban expansion and economic growth, while environmental regulations determined the cropland, grassland and forest expansions. The findings from this study seem to suggest that Zhangye should focus on ecological conservation, environment restoration, and eco-tourism as a pillar of local economic growth.