Reconciling carbon quality with availability predicts temperature sensitivity of global soil carbon mineralization

• 成果类型: Article
• 署名作者: Zhang, Shuai; Wang, Mingming; Xiao, Liujun; Guo, Xiaowei; Zheng, Jinyang; Zhu, Biao; Luo, Zhongkui
• 署名单位: Zhejiang University; Nanjing Agricultural University; Peking University; Zhejiang University; Zhejiang University
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-13977
• DOI: 10.1073/pnas.2313842121
• 发表日期: 2024-03-12
• 关键词: organic-matter decomposition; heterotrophic respiration; feedbacks; patterns; nitrogen; cycle; time

摘要

Soil organic carbon (SOC) mineralization is a key component of the global carbon cycle. Its temperature sensitivity Q10 (which is defined as the factor of change in mineralization with a 10 degrees C temperature increase) is crucial for understanding the carbon cycle- climate change feedback but remains uncertain. Here, we demonstrate the universal control of carbon quality- availability tradeoffs on Q10. When carbon availability is not limited, Q10 is controlled by carbon quality; otherwise, substrate availability controls Q10. A model driven by such quality - availability tradeoffs explains 97% of the spatiotemporal variability of Q10 in incubations of soils across the globe and predicts a global Q10 of 2.1 +/- 0.4 (mean +/- one SD) with higher Q10 in northern high- latitude regions. We further reveal that global Q10 is predominantly governed by the mineralization of high- quality carbon. The work provides a foundation for predicting SOC dynamics under climate and land use changes which may alter soil carbon quality and availability.