Microbial Ecosystem Services of Soil Formation.

Microorganisms play important roles in pedogenesis: by interacting with mineral surfaces to promote weathering and by stabilizing soil organic matter. Soil microbes degrade minerals to gain nutrients. Those nutrients increase microbial, as well as plant, biomass leading to further weathering and an increase in soil fertility. Although these general mechanisms are known, the role of specific microorganisms in these processes and the interrelationship between soil development and microbial diversity is under-studied. Recent observations suggest that mineralogy can significantly shape microbial community composition. The mechanisms for such differences likely include the accumulation of important nutrients such as P and Fe and pore size distribution corresponding to texture. Furthermore, soil microbial communities observed during primary succession appear to be highly dynamic during the first few decades and change much less over the following hundreds, thousands, and even tens of thousands of years. Better understanding the role of microbes is critical to our fundamental understanding of soil formation and to our efforts to restore ecosystems following anthropogenic disturbance.