基于InVEST模型的天山北坡城市群生境质量时空演化研究

Research on the Temporal and Spatial Evolution of Habitat Quality in Urban Agglomeration on the Northern Slope of Tianshan Mountains Based on InVEST Model

生境质量与土地利用/土地覆被类型为生物多样性所提供栖息地的适宜性有密切关系。探究天山北坡城市群土地利用引发的生境质量变化特征,揭示区域生态系统脆弱性,可为生态服务功能改善及区域生态环境保护提供一定参考。基于2000—2020年天山北坡城市群土地利用数据,采用InVEST模型从时空维度进行生境质量测算,再采用莫兰指数对生境质量空间特征进行分析。结果表明:(1)2000—2020年天山北坡城市群生境质量指数值整体在0.8以上,虽然生境质量为差和较差等级区域面积占研究区总面积的比例较高,但整体向良好和优等级方向发展;(2)天山北坡城市群生境质量由优和良好等级转为差和较差等级区域面积占比为3.75%,而由较差向差等级持续恶化的区域面积占比高达10%;(3)天山北坡城市群生境质量高值区与低值区在空间上均存在较高的正相关特征,即生境质量在空间上呈现高-高集聚和低-低集聚的两极特征,且随着时间推移,这种趋势愈发明显。总体上,研究期间天山北坡城市群生境质量空间变化幅度不大,上升区域上升的主要原因是生态工程的实施改变了区域土地利用/覆被类型,使得生境适宜性增强,而下降区域下降的主要原因是建设用地扩张。因此,建议进一步加大研究区生态保护和生态恢复措施。

Habitat quality is closely related to its suitability provided by land use/land cover type for biodiversity. In order to explore the characteristics of the changes of habitat quality caused by land use, reveal the fragility of the regional ecosystem, and provide a reference for the improvement of ecological service functions and regional ecological environmental protection, the urban agglomeration on the northern slope of the Tianshan Mountains was selected as the study area. Based on the land use data from 2000 to 2020, the InVEST model was adopted to measure the habitat quality from the spatial and temporal dimensions. Subsequently, the Moran index was used to analyze the spatial characteristics of habitat quality. The research results prove that:(1) The index of the overall habitat quality of the urban agglomeration on the northern slope of the Tianshan Mountains from 2000 to 2020 was above 0.8. Although the area with poor and worse habitat quality accounted for a higher proportion of the total study area, the overall trend is toward good and excellent development direction;(2) The habitat quality of the area of the urban agglomeration on the northern slope of Tianshan Mountains that has changed from excellent and good grades to poor and worse grades, accounted for 3.75% of the whole study area, while the area continued to deteriorate from poor to worse grades accounted of 10% of the whole study area;(3) Both the high-value Moran index areas and low-value Moran index areas of the urban agglomeration on the northern slope of the Tianshan Mountains have relatively high positive correlation characteristics in space, i.e. the habitat quality has high-high agglomeration and low-low agglomeration in space, and with time going by, this trend becomes more and more obvious. In general, the spatial change of habitat quality during the study period was not large. The main reason for the increase was that the implementation of ecological projects changed the type of land use/cover in the region, which increased the suitability of the habitat. However, the main reason for the decline was the expansion of construction land. Therefore, the ecological protection and ecological restoration measures in the study area should be further strengthened.