Assessment of carbon balance attribution and carbon storage potential in China's terrestrial ecosystem

Carbon sink in terrestrial ecosystems is critical for achieving carbon neutrality; however, its environmental sensitivity and potential remain uncertain. A comprehensive framework was established to assess the carbon balance attribution and carbon storage potential. The net ecosystem productivity was integrated with the maximum entropy model and the patch-generating land use simulation model for analysis. In 2017, ecosystems in China produce 0.44 Pg C and store 1.66 Pg C, with sources in the west and sinks in the east. The Sichuan Basin, North China Plain, Loess Plateau, Inner Mongolia Plateau and Northeast China Plain experience the historical carbon source-to-sink conversion. The potential for the sink-to-source conversion increases from central to eastern and western China and precipitation contributes 52.3%. A high possibility of potential sink-to-source conversion concentrates in Eastern Qinghai-Tibet Plateau, middle-lower Yangtze River plain and eastern coastal areas of China. The carbon sink in terrestrial ecosystems of China is expected to be 23.58 Pg C in 2030, with the central subtropical broad-leaved evergreen zone accounting for 21.33%. The risk of the decline in carbon stocks is 0.45-0.54 Pg C. The results serve as scientific references for achieving carbon neutrality and sustainable development goals.

Automated summary

Carbon sink in terrestrial ecosystems is crucial for achieving carbon neutrality and sustainable development goals. The study reveals that China's ecosystems acted as a carbon source in 2017, but the eastern region served as a carbon sink. The potential for the transformation from carbon sink to carbon source is expected to increase in central, eastern, and western China, with precipitation playing a significant role in carbon balance. Additionally, the central subtropical broad-leaved evergreen zone is identified as a key region for future carbon sequestration.