基于InVEST-PLUS模型的郑州市碳储量时空演变及空间自相关分析

Spatial-temporal Evolution of Carbon Storage and Spatial Autocorrelation Analysis in Zhengzhou City Based on InVEST-PLUS Model

[目的]陆地生态系统碳储量的主要驱动因素之一是土地利用变化,以“过去—现在—未来”的逻辑,分析河南省郑州市土地利用与碳储量时空演变之间响应关系,为实现城市的生态安全可持续发展提供参考。[方法]首先基于GIS和InVEST模型,对2005—2020年碳储量时空分布进行定量评估,然后结合PLUS模型,模拟2050年自然发展情景和生态保护情景下土地利用和碳储量时空变化特征;并辅以莫兰指数和热点分析在格网尺度下评估其空间关联程度。[结果](1)2005—2020年,耕地不断调整为建设用地,累计转入1 004.98 km^(2),致使郑州市土地利用结构发生显著变化,生态保护情景下生态用地减少趋势相对自然发展情景得到较好改善。(2)受城镇化快速扩张的影响,2005,2020年郑州市碳储量分别为6.59×10^(7),5.67×10^(7) t, 15 a间高碳密度地类用地转移,碳储量空间分布呈“西高东低,南北中等,中部低”的特点,自然发展情景和生态保护情景下碳储量变化分别减少了8.27×10^(6) t和1.80×10^(6) t,其中耕地发挥着重要碳汇作用。(3)碳储量空间分布上具有集聚性,冷热点分布不均,生态保护情景下热点破碎化程度缓和。巩义市和登封市始终为碳储量集聚程度较高区域。[结论]碳储量时空分布特征与土地利用结构变化密切相关,郑州市未来土地利用规划应适当采取生态保护措施,优化土地利用格局,增强生态系统固碳能力。

[Objective]One of the main drivers of terrestrial ecosystem carbon storage is land use change.The spatial-temporal response relationship between land use and carbon storage evolution in Zhengzhou City,Henan Province was analyzed based on the logic of“past-present-future”in order to provide references for realizing ecological security and sustainable development.[Methods]The spatial-temporal distribution of carbon storage from^(2)005 to 2020 was quantitatively evaluated using GIS and the InVEST model.Then,combined with the PLUS model,the spatial-temporal changes of land use and carbon storage were simulated for 2050 under a natural development scenario and an ecological conservation scenario.The degree of spatial correlation was evaluated at the grid scale using Moran’s I and the Getis-Ord G*i statistic for hot spot analysis.[Results]①From^(2)005 to 2020,cultivated land was continuously converted to construction land,with a cumulative transfer of 1004.98 km^(2),resulting in significant changes in the land use structure of Zhengzhou City.The decrease in ecological land area under the ecological conservation scenario was better than under the natural development scenario.②The rapid expansion of urbanization in Zhengzhou City produced carbon storage in 2005 and 2020 of 6.59×10^(7) t and 5.67×10^(7) t,respectively.Over the past 15 years,the high-carbon-intensity land class was transferred,and the spatial distribution of carbon storage was characterized by a pattern of“higher in the west,lower in the east,medium in the north and south,and lower in the central region”.Under the scenarios of natural development and ecological conservation,the carbon storage decreased by 8.27×10^(6) t and 1.80×10^(6) t,respectively,and cultivated land played an important role as a carbon sink.③The spatial distribution of carbon storage was agglomerative,with an uneven distribution of cold and hot spots.The degree of fragmentation of hot spots was moderate under the ecological conservation scenario.Gongyi City and Dengfeng City were always the regions with a high degree of carbon storage agglomeration.[Conclusion]The spatial-temporal distribution characteristics of carbon storage were closely related to changes in land use structure.In future land use planning of Zhengzhou City,people should take appropriate ecological conservation measures to optimize the land use pattern and to enhance the carbon sequestration capacity of the ecosystem.