天山北坡城市群生态承载力演变与生态敏感性分析

Ecological carrying capacity evolution and ecological sensitivity analysis of urban agglomeration in the northern slope of Tianshan Mountains

经济的快速发展及人类活动的不断加剧,造成了各种生态环境问题,对可持续发展构成了严重威胁。探讨城市群土地利用变化、生态承载力演变特征及生态敏感性分析,是推动城市群生态环境优化,提升城市群土地利用管理方式的重要理论依据。以天山北坡城市群为研究区,基于土地利用数据对天山北坡城市群2000—2020年土地利用变化进行分析,采用生态足迹模型对研究区的生态足迹及生态承载力进行推算,并结合植被覆盖度、坡度、人口密度、土地利用类型、高程5个生态敏感性因子,对天山北坡城市群进行多因子综合生态敏感性评价。结果表明:2000—2020年天山北坡城市群内建设用地和耕地转入量较大,分别增长107.79%和46.45%,林地和水域面积逐步减少,反映了天山北坡城市群在研究期内处于快速城镇化阶段,城市建成区的不断扩大对部分生态生产用地构成一定的威胁。在快速城镇化的背景下,天山北坡城市群人均生态足迹总体呈现上升的趋势,生物资源生态赤字问题仍然存在,能源为主的其他资源的生态盈余呈现缩小趋势。生态敏感性高值区域主要分布在天山北坡城市群各城市的周边地区,中度敏感地区环绕在敏感高值区周围,分别占研究区面积的11.21%和35.18%。在未来发展中天山北坡城市群需要进行区域生态敏感性的评价,针对不同的生态敏感性分区提出不同的保护和利用策略,同时需要发挥区域内各个城市的生产优势,扬长避短,实现天山北坡城市群土地资源合理利用及生态与社会及经济的高质量发展。

The rapid economic development and the continuous intensification of human activities causing various ecological and environmental problems, have posed a serious threat to sustainable development of city. For the optimization of the ecological environment of urban agglomeration, it is of great help to explore the changes of the land use of urban agglomeration, the characteristics of how its ecological carrying capacity changes, and its ecological sensitivity. These three factors above could be used as an important basis when it comes to improve the land use management of urban agglomerations. This study takes urban agglomeration in the northern slope of Tianshan Mountains as the research area, analyzes its land use change from 2000 to 2020 based on land use data, and uses the Ecological Footprint model to measure the ecological footprint and ecological carrying capacity of the study area. Combined with five ecological sensitivity factors including vegetation coverage, slope, population density, land use type, and elevation, a multi-factor comprehensive ecological sensitivity evaluation was carried out on urban agglomeration in the northern slope of Tianshan Mountains. The results show that from 2000 to 2020, the transfer of construction land and cultivated land within the agglomeration was relatively large, increasing by 107.79% and 46.45% respectively, and that the area of forest land and water area have gradually decreased. These factors reflected that during the time urban agglomeration in the northern slope of Tianshan Mountains was in the stage of rapid urbanization, where the continuous expansion of urban built-up areas posed a certain threat to some ecological production land. In such context, the per capita ecological footprint of the urban agglomeration has generally shown an upward trend, the ecological deficit of biological resources still existed, and the ecological surplus of other resources(mainly energy) has shown a shrinking trend. The highly-sensitive area of ecological sensitivity were mainly distributed in the surrounding areas of the cities, covering the area of 11.21% of the urban agglomeration, meanwhile the moderately-sensitive areas surrounded the highly-sensitive areas, accounting for 35.18% of the target area. For the future development of urban agglomeration in the northern slope of Tianshan Mountains, it is necessary to conduct an evaluation of regional ecological sensitivity, and propose different protection and utilization strategies for different ecologically sensitive zones. In the meantime, advantages of each city in the region shall be fully considered to promote the rational use of land resources and to improve the development ecologically, socially and economically.