| Desert and oasis is in the arid region ecological environment both are independent of each other and influence each other contradictory unity,oasis ecological landscape as strong heterogeneity of desert region,simple ecological structure,ecological fragility is extremely strong,is a desert region of human subsistence,sustained by oasis the lifeblood of economic development,social development and people’s life.In the process of large-scale development of oasis resources and economic revitalization by human beings,the unreasonable large-scale development makes desert oases,which are scarce in resources,fragile in environment and have extremely limited ability to resist natural disasters and man-made disturbances,bring devastating ecological security problems.Identifying and protecting ecological networks that are critical to regional ecological security can provide win-win solutions for economic development and ecological protection.In this paper,the theory of ecological risk assessment is introduced into the construction of Oasis Urban Green Infrastructure Network,which provides a new framework for OASIS Urban Ecological Security,it can provide basic ecological security barrier and Development Control Framework for OASIS CITY development which is short of resources,fragile ecology and lack of planning and investment,and finally realize rational planning of Oasis Resources and effective control of urban sprawl.To achieve the goal of maintaining the security of Oasis ecological space and ensuring the security of OASIS Ecological Network.This research is divided into three parts:(1)Through in-depth analysis of the current situation of the ecological environment in oases,the main formative factors of the deterioration of the ecological environment in oases were summarized,and the P-S-R model was used as the evaluation framework,combined with the existing data,from three aspects of pressure,state and response,based on this frame,the factors of each index layer are calculated,and finally the grid map of Oasis comprehensive ecological risk value is obtained by using the method of comprehensive ecological risk index,the results were divided into six risk levels.(2)Choose the ecological source from the aspects of reducing the probability of environmental problems caused by ecological risk,systematicness of ecological structure and integrality of ecological process.First of all,according to the results of ecological risk assessment,select the source of low risk level.Through the analysis of morphological spatial pattern(MSPA)and landscape connectivity,the higher connectivity patches were identified as the source,and the aim of OASIS ecological structure system and process integrity was achieved.Finally,on the basis of ecological risk background assessment,the ecological source into the ecological risk source classification,the final analysis of the ecological risk is very high,urgent need to protect the source,as a priority.(3)Constructing a comprehensive resistance surface to simulate the best path between the sources as a potential ecological corridor,and based on this,introducing other measuring methods as a gravity model to extract the important ecological corridor of Oasis;Then,the intersection of the minimum and maximum consumption path and the weakest point of the ecological corridor are extracted by the ecological resistance surface model to determine the ecological node,and the regional green infrastructure network is formed initially Finally,based on the goal of ecological risk prevention and control,the uncovered areas in the source area were identified as the regions to fill the ecological source area gaps.In order to improve the connectivity of the network and the function of ecological risk protection,the green infrastructure corridor was optimized with the optimized source area.(4)Supervision strategies were proposed for the overall spatial ecological risk assessment results of the oasis,and control measures and suggestions were put forward for ecological sources and ecological corridors respectively according to the results of green infrastructure network construction. |
