[Prospects for Organic Carbon Turnover Process and Soil Carbon Enhancement Regulation in Saline Farmland]

Salinization of farmland is one of the obstacles affecting agricultural production. Saline farmland management has the potential to increase carbon and fertilizer efficiency and scientifically improve the soil fertility of saline farmland, a crucial factor for comprehensively improving the quality of arable land in China. Fully tapping into the carbon sequestration potential of saline farmland is a key step in enhancing its role as a carbon sink. It is important to understand the constraining factors and mechanisms of soil carbon turnover in saline farmland, suppress the process of secondary salinization of farmland, improve the storage and stability of soil carbon sinks in farmland, improve the overall quality and output value of farmland, and promote ecological civilization construction in China. Based on recent research progress, this study introduces the impacts of salinization on soil organic carbon pools at all levels, compares the differences in soil organic carbon pools between saline and conventional farmlands, highlights the crucial role of soil salinity in organic carbon turnover, summarizes the ways to regulate soil carbon sequestration and soil fertility enhancement in saline farmland, and proposes potential research for carbon sequestration, expansion of soil organic carbon pools, and soil fertility in saline farmland. Under the influence of salinization, soil aggregates in farmland disintegrate, and the stability of organic carbon pools at all levels decreases. The high salt content in the soil can affect various aspects of soil carbon cycling, such as reducing external carbon input, weakening the protective effect of soil aggregates on organic carbon, and interfering with the typical activities of soil microorganisms. Reasonable use of exogenous organic materials, agricultural practices, and regulation of microbial stimulation effects have shown positive results in increasing carbon and fertilizing in saline farmland. In the future, we should improve the stability of soil aggregates in saline farmland, reduce the loss of soil organic matter and nutrients caused by salinization, and comprehensively consider the impact of salinization on soil organic carbon input, mineralization, fixation, decomposition, and utilization. Furthermore, improvement is needed in the theoretical model of carbon turnover in saline farmland, along with in-depth research on scientific methods for soil obstacle removal and carbon enrichment.