Research On The Evolution And Optimization Of Green Space In Qitaihe City Based On Ecosystem Services

Urban ecosystem services play a key role in enhancing the well-being of urban residents and sustainable urban development.Urban green space is the core carrier of urban ecosystem services,which has important functions such as regulating climate,keeping water and soil,and maintaining biodiversity.As a resource-based city,Qitaihe City is becoming more and more prominent in urban ecological environment with the gradual reduction of resource extraction and accelerated urbanization,which is not conducive to the function of ecosystem services in green space.The optimization of urban green space pattern based on ecosystem service function is conducive to guiding the rational utilization use of land space,enhancing the ability of urban ecological security and resisting ecological risks,providing ecological guarantee for the transformation and development of resource-based cities,and realizing the sustainable development of regional ecological environment and social economy.This study is guided by the relevant theories of landscape ecology,landscape architecture and urban planning,and takes Qitaihe City as the research object.Firstly,based on the remote sensing interpretation data of land use in 2000,2010 and 2020,the evolution characteristics of green space and the evolution results of Qitaihe city are analyzed by using the methods of land use dynamic attitude analysis,land use transfer matrix model and landscape pattern index analysis.Secondly,combined with the natural environment and social and economic development needs of Qitaihe City,the evaluation framework of ecosystem services in Qitaihe City is constructed from four aspects: supply,regulation,support and culture.The function of green space ecosystem services is assessed by In VEST model and value equivalent method,and the spatial and temporal variation characteristics and causes of green space ecosystem services are deeply analyzed.Finally,based on the current situation of green space in Qitaihe City,the optimization goal of green space pattern is proposed,and use the morphological spatial analysis method and circuit theory model based on the comprehensive ecosystem service index to optimize the green space pattern through the research paradigm of "ecological source identification-resistance surface setting-ecological corridor extraction-ecological node identification".The research paradigm is used to optimize the components of green spatial pattern and build a green spatial pattern optimization system.The main research results are as follows:(1)During 2000-2020,the landscape structure and landscape pattern of green space in Qitaihe City changed significantly.From the perspective of landscape structure,the total area of green space shows a trend of decreasing first and then increasing,experiencing an evolutionary process from destruction to restoration,which is closely related to the change of urban industrial structure.Most of the conversion of green space land types is concentrated within the green space,with the most significant conversion from cultivated land to forest land,and a small part of green space is negatively converted into construction land.From the viewpoint of landscape pattern,the landscape pattern of green space as a whole shows fragmentation and differentiation,and the landscape connectivity and diversity of green space in the eastern and central part of the study area decreases significantly.(2)During 2000-2020,the changes in the functions of various ecosystem services of green space in Qitaihe were distinct.As a whole,the integrated ecosystem services of all green space types except waters have increased.The mountainous and hilly areas in the southwest and northeast of the study area have strong comprehensive ecosystem service functions,while the watershed and arable land have weaker integrated ecosystem service functions due to greater interference from human activities,and should be focused on in future urban planning.(3)Based on the results of comprehensive ecosystem service assessment,34 important ecological sources were identified,15 core corridors were extracted and 48 core ecological nodes were identified in combination with the comprehensive ecological resistance surface,and the core components of green spatial pattern were optimized on its basis to build a green spatial pattern optimization system,with a view to providing scientific reference for the transformation and development of Qitaihe City and the formulation of relevant government decisions.