Research advances in mechanisms of climate change impacts on soil organic carbon dynamics

Abstract

Soil, as the largest terrestrial carbon pool, has garnered significant attention concerning its response to global warming. However, accurately estimating the stocks and dynamics of soil organic carbon (SOC) remains challenging due to the complex and unclear influence mechanisms associated with biogeochemical processes in above- and belowground ecosystems, as well as technical limitations. Therefore, it is imperative to facilitate the integration of models and knowledge and promote dialogue between empiricists and modelers. This review provides a concise SOC turnover framework to understand the impact of climate change on SOC dynamics. It covers various factors such as warming, precipitation changes, elevated carbon dioxide, and nitrogen deposition. The review presents impact mechanisms from the perspective of organismal traits (plants, fauna, and microbes), their interactions, and abiotic regulation. Although valuable insights have been gained regarding SOC inputs, decomposition, and stabilization under climate change, there are still knowledge gaps that need to be addressed. In the future, it is essential to conduct systematic and refined research in this field. This includes standardizing the organismal traits most relevant to SOC, studying the standardization of SOC fractions and their resistance to decomposition, and focusing on the interactions and biochemical pathways of biological communities. Through further investigation of biotic and abiotic interactions, a clearer understanding can be attained regarding the physical protection, chemical stability, and biological driving mechanisms of SOC under climate change. This can be achieved by integrating multidisciplinary knowledge, utilizing novel technologies and methodologies, increasing in-situ experiments, and conducting long-term monitoring across multi-scales. By integrating reliable data and elucidating clear mechanisms, the accuracy of models can be enhanced, providing a scientific foundation for mitigating climate change.

Keywords

• soil organic carbon (SOC)
• climate change
• biogeochemical processes
• organismal traits
• inter-organism interactions
• abiotic regulations