Spatial and temporal trade-offs between carbon storage and crop production in Chinese terrestrial ecosystems, 1995–2100

Abstract

The cascading process of urban-cropland-ecological land (forest and grassland) in China has been initially reported, however, the characteristics of the long-term trade-offs in carbon storage and crop production induced by this process are not clear, which has become a key challenge for policy management of urbanization and food-ecological security in China. This study integrated multi-sources data, random forest and carbon storage models to assess the spatiotemporal variations in carbon storage at national and regional scales (1995–2100). Combined with the Chinese crop production dataset, we identified the spatiotemporal trade-off changes in crop production-carbon storage using overlay analysis and spatial mapping methods. It was found that the area of urban expansion increased nearly threefold in 1995–2020, but there were obvious regional differences, and the area of ecological land decreased, while the total carbon storage increased. In the scenario period (2021–2100), the total carbon storage increases in the three scenarios (SSP1-2.6 > SSP2-4.5 > SSP5-8.5), showed a spatial increasing trend from north to south. Most of the service decline zones are located in the Huang-Huai-Hai Plain and Northwest region, the food security zones and the eco-security zones occupy the north and the south, and the synergistic development zones are mainly located in the Qinghai-Tibet Plateau. In SSP1-2.6, the cities with synergistic development has increased by 36, and the cities with declining services decreased by 68; the number of cities experiencing synergistic development has decreased by 20 in SSP5-8.5, while the number of cities facing service decline has risen by 6, casting shadows on the prospects for sustainability; the changes in synergistic and decline zones are relatively stable in SSP2-4.5. The SSP1-2.6 scenario pathway will improve carbon storage in China’s terrestrial ecosystems and regional synergistic crop production supply. By revealing the ecological effects of cascading changes in regional landscape patterns, this study can provide theoretical references and data support for the integrated design and management of new urbanization, food security and ecological restoration projects.