Ecological Security Assessment Based On Land Use/Land Cover

Ecological security is an important goal of environmental management,and it is very important to realize the sustainable development of human society.Among many factors affecting ecological security,land use/land cover change(LUCC)is the most active and main driving force,and its type and area directly affect ecological security.However,in recent decades,because of the continuous advancement of human society and the continuous pursuit of life quality,the land use/cover situation in many regions around the world has changed dramatically,leading to a large number of ecological damage problem.Hexi region has a vulnerability environment as a result of drought.The social and economic development of the Hexi region is directly affected by the three inland river basins,and the Qilian Mountains upstream of the Hexi region play important ecological functions such as water conservation and biodiversity protection in China.Since the 21 st century,with the continuous promotion of the policy of western development by the Chinese government,the social economy in Hexi region has been developing rapidly,but it also inevitably brings a series of ecological and environmental problems.Therefore,realizing the characteristics of LUCC in the Hexi region and evaluating its ecological security status scientifically are essential to achieve ecological security.In this study,the land use/cover data of the Hexi Region from 2000 to 2015 were analyzed by using Arc GIS software,and the detailed situation of LUCC was obtained.Secondly,combined with four types of physical geographic data(elevation,slope,rainfall,temperature)and six types of social and economic data(POP,GDP,railway,expressway,national highway,provincial highway),the Future Land Use Simulation(FLUS)model was used to forecast the land use/cover scenario in 2030 in the Hexi Region.Finally,based on the theory of ecological security system,simultaneous two aspects of ecological health and ecological risks,ecological security evaluation model is set up,to explore the measures and ways of ecological restoration in the Hexi region,so as to provide decision-making basis for sustainable development in the region.The main conclusions of this study are as follows:(1)The change of land use/land cover during 2000-2015 showed that the change of land use types in Hexi region mainly focused on the increase of farmland and building and the decrease of unused land and desert,while the other land use/land cover areas remained basically unchanged.During the study period,with the continuous development of social economy,the area of cultivated land and building land continued to increase.The land use transfer matrix shows that unused land,farmland,grassland,desert and building are the main land use types transferred or transferred.Benefit from the project of "Grain to Green" and the advancement of scientific and technological level,the range of grassland transformation has gradually decreased,and the increase of farmland and building land mainly comes from unused land and desert.(2)By selecting a series of physical geographical factors such as elevation,slope,precipitation,temperature and human factors such as road,POP and GDP,the FLUS model can well simulate the future land use/land cover situation in the Hexi Region.The Kappa coefficient is 0.8558,far exceeding the simulation standard of 0.72.(3)The ecological security assessment framework established by combining ecosystem health and ecosystem risk can effectively assess the status of ecological security.During 2000-2015,there was no significant change in ecological security in Hexi region.From 2000 to 2010,due to the change of unused land and desert to farmland,the regional ecological security situation showed a good trend.From 2010 to 2015,the ecological security situation declined slightly due to the large increase of building.However,according to the forecast results,the ecological security situation in the Hexi region will be significantly reduced by 2030 due to the large increase of building and farmland.(4)To promote the level of ecological security in the Hexi region,this study comes up with some suggestions and measures,such as strengthening the protection of natural forest and grassland,controlling the building’s unordered expansion,and paying attention to improving the quality of farmland.