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

Abstract

[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 2005 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] ① From 2005 to 2020, cultivated land was continuously converted to construction land, with a cumulative transfer of 1 004.98 km2, 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. ② The rapid expansion of urbanization in Zhengzhou City produced carbon storage in 2005 and 2020 of 6.59×107 t and 5.67×107 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 8.27×106 t and 1.80×106 t, respectively, and cultivated land played an important role as a carbon sink. ③ The 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.

Keywords

• carbon storage
• land use change
• spatial autocorrelation
• getis-ord gi
• zhengzhou city, henan province