Objective Dissolved organic carbon (DOC) is an important activated carbon component in the soil carbon pool and is relatively sensitive to environmental changes. Climate warming can alter the production and accumulation of DOC by influencing microbial activities and the decomposition of organic matter. Although previous studies have reported the response of soil DOC to simulated warming, there was a lack of an overall assessment and analysis of the mechanism of action of influencing factors. This study integrated and analyzed the published literatures to investigate the dynamic response of soil DOC under the influence of warming conditions (warming period, warming gradient and warming method) and environmental factors (annual average temperature, annual average precipitation, ecosystem and soil layer).

Result The results showed that short-term warming (less than 1 year), warming gradient, open-top chamber warming, and altitude-induced warming tended to promote DOC accumulation. However, under the condition of warming over 1 year, soil interior warming, and infrared warming exhibited no significant effect on DOC accumulation. Warming promoted the accumulation of DOC in different soil layers, which was more pronounced in topsoil compared to deeper layers. Compared with forests and farmlands, the soil DOC accumulation in grasslands and wetlands responded more significantly to warming. In conclusion, the increase in environmental temperature generally promoted the accumulation of DOC in soil, but this accumulation effect showed certain differences under the regulation of soil layers, ecosystem types, annual average temperature and annual average precipitation.

Conclusion This results contributed to our understanding of the effect of warming on DOC, and played an important role in elucidating the intricacies of the soil carbon cycle and its feedback mechanisms within the context of global warming.