Abstract:It is important to identify the key areas of ecological protection and optimize the ecological spatial structure in Xinjiang, it means a lot to promote the harmonious development of oasis economy and ecological environment, and to enhance human welfare. Taking Baicheng County as the study area, on the basis of fully considering the level of ecosystem service function, the core ecological "source" areas of environmental protection were determined through the comprehensive evaluation of ecosystem service value. We also used the least resistance model, combined with the GIS spatial analysis technology and CA-Markov model, to identify the ecological security pattern, analyze its trend of development and improve the ecologically spatial network system of Baicheng County. The results showed as follows:(1) During the study period, the total value of ecosystem services in Baicheng County has increased gradually, among which the value of water conservation and waste treatment increased the most, while the growth rate of each ecosystem service type had a little difference. (2) According to the ecological security pattern of Baicheng County in 2009, 2016 and 2019, the overall environmental security layout was characterized by the uneven distribution of source areas, broken corridor structure, low network degree, and large area of ecologically fragile regions. (3) According to the ecological protection pattern in 2009, 2016 and 2019, based on the changing trend of ecological "source" sites and ecological protection importance sites, we simulate the distribution of ecological "source" sites and their importance levels in 2029. Based on the county's natural and geographical characteristics as well as the overall development plan, we also put forward the ecologically spatial layout system of Baicheng County. That is "two belts, three functions, four districts, multiple centers and ten corridors", which provides a reference for the ecological security and regional ecological civilization construction in the oasis area.