黔中城市群碳储量对土地利用/覆被变化的响应及脆弱性

[目的] 探究土地利用/覆被变化对区域生态系统碳储量及生态系统脆弱性的影响,以期为区域绿色低碳和生态系统的可持续发展提供参考依据。[方法] 以2000,2010,2020年黔中城市群核心经济区3期土地利用/覆被数据为基础,运用InVEST模型和土地利用转移矩阵定量分析生态系统碳储量及其空间分布格局,并采用潜在影响指数(PI)对区域生态系统服务脆弱性进行评估。[结果] ①2000-2020年,黔中城市群核心经济区土地利用/覆被变化总体表现为耕地和林地持续下降,建设用地持续上升。研究区土地利用/覆被转移主要表现为耕地、林地、草地向其他地类的转移,其中,2000-2010,2010-2020年分别有3 339.35,3 669.15 km²土地发生了转移,前者林地转为草地是主要转移类型,后者耕地转为建设用地为主要转移类型。②2000-2020年区域的碳储量表现为减少趋势,由4.42×10⁷ t减小到4.33×10⁷ t,累计减小9.40×10⁵ t,林地转为草地是引起碳储量减少的主要原因。各年度碳储量密度均呈现西部、东部高,中部低的分布态势;20 a间,高密度区未发生明显变化,低密度区表现为由中心区域向外围扩散。③2000-2020年黔中城市群核心经济区主要扮演碳源的角色,土地利用程度指数增加了2.83,PI指数分别为-0.04,-0.31,均表现为负面潜在影响,且脆弱性不断增强。[结论] 增加林地、控制林地转为其他用地及建设用地扩张是促进区域绿色低碳和生态系统的稳定可持续发展的重要手段。

Response of Carbon Storage to Land Use/Cover Changes and Vulnerability for Central Guizhou Urban Agglomeration

[Objective] The impacts of land use/cover changes on carbon storage and ecosystem vulnerability in regional ecosystems were determined in order to provide a reference for regional green low-carbon and sustainable development of ecosystems.[Methods] The ecosystem carbon storage and its spatial distribution pattern were quantitatively analyzed by using land use/cover data for the core economic zone of the Central Guizhou urban agglomeration in 2000, 2010, and 2020 with the InVEST model and a land use transfer matrix. A potential impact index (PI) was used to assess the vulnerability of regional ecosystem services.[Results] ① Land use/cover changes in the core economic zone of the Central Guizhou urban agglomeration showed that cultivated land and forest land continued to decline from 2000 to 2020, and construction land continued to increase. Land use/cover changes in the study area were mainly manifested as the transfer of cultivated land, forest land, and grassland to other land use types, among which 3 339.35 and 3 669.15 km² of land were transferred from 2000 to 2010 and 2010 to 2020, respectively. The conversion of forest land to grassland was the main transfer type during the first period, and the conversion of arable land to construction land was the main transfer type in the second period. ② Regional carbon storage decreased from 2000 to 2020 (from 4.42×10⁷ to 4.33×10⁷ t), with a cumulative decrease of 9.40×10⁵ t. The conversion of forest land to grassland was the main reason for the reduction in carbon storage. The carbon storage density in each year was higher in the west and east, and lower in the middle portion of the study area. There was no significant change in the high density area during the past 20 years, while the low density area spreading from the central area to the periphery. ③ The core economic zone of the Central Guizhou urban agglomeration was the main source of carbon from 2000 to 2020, with the land use degree index increasing by 2.83, and PI index being -0.04 and -0.31, respectively, showing negative potential impact and increasing vulnerability.[Conclusion] Increasing forest land, controlling forest land conversion to other uses, and expanding construction land are important means for promoting regional green, low-carbon, stable, and sustainable development of ecosystems.