Conservation agriculture-mediated soil carbon sequestration: A review

Soil organic carbon (SOC) sequestration is an important driving force for mitigating global climate change and maintaining farmland productivity. Clarifying the accumulation and stabilization mechanism of SOC and its influencing factors can help regulate the soil carbon (C) sink potential scientifically. In addition, under the challenge of global ecological environment degradation and food security pressure, seeking sustainable farmland management has become an urgent task. Conservation agriculture (CA) has an important impact on SOC sequestration and helps to achieve a win-win situation between food production and ecological benefits. However, given the complexity of soil systems, a systematic theory of soil C pool formation under the control of CA has not yet been formed. In this context, a review is presented with the introduction to and discussion on different sequestration pathways of SOC and its stabilization mechanism, the connotation and main components of CA, and the effect of conservation CA on SOC sequestration. Besides, the mechanism of SOC sequestration under the regulation of CA is discussed in detail. On the basis of existing study, modern organic C separation and biomarker technologies should be used to clarify the microbial-aggregate-mineral synergistic mechanism of SOC sequestration mediated by CA, and pay attention to the deep soil C sequestration process. In addition, the establishment of a long-term study system for CA will contribute to improving the regulation of CA on the potential and essence of SOC. finally, a SOC management framework based on farmland practice should be built to help land managers and farmers to formulate scientific and reasonable sustainable land use strategy.