The progression of the development of soil as organic matter
accumulates during the lab experiment.
This recent publication of University of New Hampshire Agricultural Experiment Station’s work on soil organic matter uncovered some very interesting findings. According to researchers, the commonly held belief that plants are the origins of soil organic matter is not accurate. Apparently soil organic matter is really the accumulation of dead microbial cells and their byproducts (formed when microbes eat plant roots and residues).
Researchers demonstrated that “accumulation of significant amounts of chemically complex, persistent soil organic matter from microbial materials” can occur “in the absence of any plant inputs”; is “almost identical to natural, field-derived soil organic matter when fed nothing but table sugar”; and its “accumulation is greatest when more–not less–active microbial biomass is formed… especially when that biomass is produced more efficiently, meaning more of the substrate is converted to biomass rather than carbon dioxide”.
Seems to me, our efforts therefore need to be focused on encouraging and protecting lots of active, diverse microbial biomass – such as less tillage, multispecies inter-cropping, and fertility programs focused on microbial needs.