Abstract: Background, aim, and scope The evaluation of urban green space can provide important support for the scientific planning and management of urban green space and realize the sustainable development of urban green space. The division of health level of green space can provide important information for the management strategy of green space, such as species selection and adjustment of vegetation structure. Etc.; The analysis of greenland vegetation ecological risk sources and the classification of risk levels can alleviate or eliminate stressors for green areas, and on the other hand, formulate corresponding countermeasures for green space health, providing important information for rational planning and management of green space in the next step. By constructing the urban green space ecological evaluation index system, the paper makes a scientific evaluation of the urban green space in Jiayuguan City, and uses certain models to identify the influencing factors affecting the ecological level of the urban green space. It is hoped that people will correctly understand and transform the urban green space construction as a follow-up city. Green space planning and management provide theoretical references. Materials and methods With the urban green space of Jiayuguan city from 2007 to 2016 as the research object, the ecological evaluation index system of urban green space is constructed from three aspects, and the obstacle degree model is adopted to identify the obstacle factors that affect the ecological level of urban green space. Results In the past 10 years, the comprehensive value of urban green space ecological level of Jiayuguan city has gradually increased, and the level has been raised from the lower level to the higher level. However, at present, the ecological level of urban green space belongs to the low level and unstable high level, and the construction pressure of urban green space is still great. From the perspective of criteria, the main threats to the ecological level of urban green space in Jiayuguan are obvious, and the quantity index and structure index are the main obstacles. From the index level, the main obstacle factors are different from year to year, and the biggest obstacle factors have evolved from per capita park green space area, tree species richness to air purification capacity. Discussion Urban green space evaluation initially focused on green space structure and ecological function, then gradually expanded to green space ecological services, ecological health level and ecological risk, and finally developed to sustainability evaluation. Urban green space more attention in the study of urban green space's ecological functions and ecosystem services, and concentrated in the eastern central region, based on "oasis" Jiayuguan city green space as the research object, from the aspects of quantity, structure, function of three comprehensive evaluation of the urban green space ecology level, using the disorder degree model to identify the obstacle factors of the development of urban green space, for the improvement of other urban ecological problems in arid areas provides a certain reference. Conclusions From 2007 to 2016, the ecological level of urban green space in Jiayuguan City gradually increased to a low-level, unstable high-level order. The barrier factors varied greatly in different years, and the biggest obstacle factor experienced the evolution from per capita park green area, tree species richness to air purification capacity. Recommendations and perspectives The urban green space evaluation initially focused on the green space structure and ecological function, and subsequently expanded to the green space's ecological service, ecological health level and ecological risk, and finally developed to sustainability evaluation. At present, the research on urban green space pays more attention to the ecological function and ecosystem service of urban green space, and concentrates on the eastern and central regions. The article takes the urban green space of Jiayuguan in the “desert oasis” as the research object, and comprehensively evaluates it from three aspects: quantity, structure and function. The ecological level of urban green space, using the obstacle model to identify the obstacle factors that restrict the development of urban green space, provides a reference for the improvement of ecological problems in other cities in the arid region.
Keywords: urban green space; green space ecology; obstacle model; Jiayuguan city