Effects of simulated warming on content, fractions and chemical structure of soil organic carbon:Progress and prospects.

Soil organic carbon (SOC) represents the largest terrestrial organic carbon pool and plays an important role in mitigating global climate change. Warming can change the stabilization process and the balance of inputs and outputs of the SOC pool, thereby affecting the content, fraction, and chemical structure of SOC. It has become a research hotspot to reveal the mechanisms underlying the effects of warming on SOC stability by analyzing the fraction and molecular structure of C. Here, we reviewed the warming effects on the SOC pool from three aspects, e.g., the content, fraction, and chemical structure of SOC. We also summarized the response of key ecosystem processes to warming, including plant productivity and community composition, microbial activity and community structure. We highlighted the importance of prospective and systematic research focusing on elucidating the microbial mechanism, identifying SOC source and turnover processes, establishing long-term dynamic networked experiments, and mining and optimizing key parameters in C cycle models. This would provide theoretical support for better understanding the change and mechanism of SOC under global warming and predicting the alterations of SOC pool under climate change.