Urban Green Land Ecological Suitability Assessment Based on GIS in Arid Areas: Beitun City, Xinjiang, as an Example

Arid areas are faced with frequent droughts and sandstorms, and through variations of the harsh natural conditions. Urban green space is an important ecological infrastructure to improve the harsh climate, but green space system planning often exposes strong subjectivity. The suitability evaluation of urban green space can be based on the powerful spatial analysis capabilities of GIS, through investigation and comprehensive analysis of the suitability of the land for various uses, the level of quality and its restriction status, etc., so as to classify and grade the ecological functions of urban green space. Taking Beitun city in Xinjiang Province as an example, according to local conditions, evaluation factors were selected from five aspects: wetland resources, flora and fauna habitat, landscape features, anthropogenic disturbance and temperature risk; the factor weights were determined by analytic hierarchy process; a green space suitability evaluation system based on three levels of "target-criterionindex" was established, and on this basis. Using the GIS spatial overlay analysis module, five levels of urban green space ecological suitability zones were delineated: the most suitable green area (23.6%); the high-suitability area (32.1%); the mid-suitability area (21.6%); the low-suitability area (14.5%); and the unsuitable area (8.2%), Combined with the current situation of land use and the demand of urban development in Beitun city, the functional zoning of urban green space ecological facilities arc divided into a green ecological restoration area, a green ecological conservation area, low-and medium-impact development areas and a green suitable development area; on a scientific basis, allocation of green space resources and protection countermeasures are proposed to construct green space in each area as part of the theoretical guidance for Beitun. The results show that appropriate indicators and methods can more accurately reflect the actual and demand of urban green space development in arid areas, and play a practical guiding role. The research provides a useful attempt and supplement for the practice and application of the method of division of green space ecological suitability in arid cities.