Tingting Zhang Zhenrong Du Jianyu Yang Xiaochuang Yao Cong Ou Bowen Niu Shuai Yan
In order to protect the ecological environment and solve the poverty problem in the westernregion, China has established an ecological migration (EM) policy. This policy aims to relocatepopulations from poverty-stricken areas with fragile ecological environments, which inevitably leadsto changes in land cover and the ecological environment. The objective of this study was to identifythe effects of EM in a typical region (Wuwei), including changes in the land cover and ecological risk(ER). A land cover change monitoring method was implemented for the 2010–2019 period for sixland cover classes using random forest, which is an effective supervised machine learning method.The land cover change patterns were analyzed by determining the area changes of the six classesand applying a land use transition matrix, and a landscape ecological risk model based on landscapedisturbance and fragility was used. Our results demonstrate that the increase and decrease in thearea of cultivated land, unused land, and construction land can be divided into two stages (2010–2015and 2015–2019). The area of water and perennial snow doubled during the study periods. The majorland cover transitions were between unused land and construction land and between unused landand crop land. In addition, the ER value for the Qilian Mountain National Nature Reserve decreasedbecause of the implementation of EM in the study area, indicating that the ecological environmentwas effectively improved. The results demonstrate the advantage of the proposed approach inunderstanding the impact of EM on regional land cover changes and the ecological environment soas to provide guidance for follow-up planning and development.
Keywords: random forest; ecological migration; land cover change monitoring; ecological risk; Google Earth Engine