These latest findings complement previous work showing how microbial action influences soil structure – helping Rothamsted scientists develop an overarching Theory of Soil.
In healthy soils, relatively low nitrogen levels limit the ability of microbes to metabolise carbon compounds. These are instead excreted by the organism in polymers (called extracellular polymeric substances, or EPS) that can act as a kind of glue.
EPS stabilises the aggregation of soil particles in the environment adjacent to the microbe. This makes the physical structure of the environment around these microbes more stable to disruption, such as occurs when the soil wets up and dries, or when plant roots pass nearby.