The transformation and stabilization of soil organic carbon (SOC) represent a central process in the global carbon cycle, exerting profound implications for climate change and directly influencing soil fertility and land productivity enhancement. Current research primarily focuses on the microbial carbon pump (MCP), emphasizing the role of microbial metabolism and necromass in forming stable carbon pools. However, the mechanisms through which biotic network interactions regulate microbial necromass production and influence SOC formation and fertility enhancement remain insufficiently understood. This review focuses on dryland red soil ecosystems and systematically elucidates how interactions among plants, microorganisms, and soil fauna drive SOC accumulation through the coordinated action of the MCP. Building on this understanding, we propose management strategies to enhance SOC sequestration and soil fertility, including optimizing carbon inputs and selectively constructing biotic networks. Finally, we identify key scientific questions that require further investigation under this integrative framework.