Urban-rural disparities of carbon storage dynamics in China's human settlements driven by population and economic growth

• Published in: The Science of the total environment 2023-05, Vol.871, p.162092-162092, Article 162092
• Main Authors: Jiang, Huiping, Guo, Huadong, Sun, Zhongchang, Yan, Xiongfeng, Zha, Jinlin, Zhang, Haili, Li, Sijia
• Format: Article
• Language: English
• Subjects: Big Earth data; Carbon - analysis; Carbon storage change; China; Economic Development; Ecosystem; Humans; Rural revitalization; Soil; Soil sealing; Urban expansion; Urbanization
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2023.162092

China has experienced a rapid expansion of human settlement in both urban and rural areas over the past three decades. Regarding the impacts on carbon storage, previous studies that only focus on certain ecosystems cannot reflect urban-rural disparities, resulting in the carbon storage changes in human settlement remaining unknown. In this study, we aimed to explore China's urban-rural disparities in human settlement expansion and direct impacts on carbon storage by using the big Earth data technology. The results showed that from 1990 to 2018, the total amount of China's human settlement expansion reached 175,703.80 km2, and the inner-city, peri-urban, and rural components accounted for 21.00 %, 20.18 %, and 58.82 %, respectively. Along with the general tendency of impervious surface area (ISA) growth, there was more soil organic carbon (SOC) (1254.33 TgC) being sealed beneath ISA (0–100 cm depth), compared to a huge reduction in vegetation biomass carbon (VBC) (91.44 TgC) during the study period. The results further indicated that the change density of either VBC or SOC presented a slightly rising trend along the urban-rural gradient, due to the increasingly common encroachment on vegetation and soil types with higher carbon content. We also found that socioeconomic drivers had a greater influence in urban areas than rural areas, and the related correlation exhibited a descending trajectory in both urban and rural areas. There is thus an urgent need to preserve lands with abundant carbon storage and contain the waste of land resources in rural areas. All stakeholders should pay more attention to concerted and targeted regulation policies for well-planned and eco-friendly human settlement expansion such as enhancing rural land use efficiency and promoting large-scale afforestation and continuous urban greening, which will be critical not only for guiding sustainable urbanization all over China but also for mitigating climate change for the entire world. [Display omitted] •China's urban-rural disparities of human settlement growth were explored uniformly.•We quantified the carbon storage change in impervious surfaces from 1990 to 2018.•The favorable carbon sequestration was impaired by soil sealing and vegetation loss.•The carbon storage change density showed a slightly rising trend due to land take.•Socioeconomic drivers exerted a greater influence in urban areas than rural areas.