It is well recognized that microorganisms are central to soil ecological processes. However, more unknowns exist than knows yet in terms of the knowledge of soil microbes despite their acknowledged importance in the ecosystems. For example, it remains largely unknown how microbe-mediated processes link litter decomposition with soil organic matter formation, turnover, and sequestration. Here, we give a presentation based on two aspects: dead microbes from anabolism and living microbes for catabolism, both of which have been highlighted under the categories of Soil Biogeochemistry and Microbial Ecology field, respectively. We posit that linking these two microbial aspects together will enrich our understanding of the decomposition, transformation and sequestration of soil organic carbon under environmental perturbations, such as land use and climate change.
Results/Conclusions
To this end, we define two pathways, ex vivo modification and in vivo turnover, in which microbes drive soil carbon dynamic via microbial catabolism and/or anabolism. Accordingly, we propose a conceptual framework, in which a raised concept – “microbial carbon pump” describes how microbes act as an active player to accumulate carbon in soils, defined as microbial “entombing effect”. We hypothesize that the long-term microbial assimilation process may facilitate the formation of a set of organic compounds that are stabilized, whether in protection by physical interaction or in lack of activate energy due to chemical inertness, ultimately leading to the entombment of microbial-derived C in soils. Further, we discuss potential influential factors that may change the microbial carbon pump for carbon entombment in soils, and finally provoke increased efforts and inspire new areas where we see a need for advancing our relevant knowledge.