The mineralogy of microbial ecology

摘要

Mineralogy, microbial ecology, and mineral weathering in the subsurface are an intimately linked biogeochemical system. We have documented microbial silicate weathering driven by the nutrient requirements of the microbial consortium when the required elements are present as trace mineral inclusions. This relationship has been identified in an anoxic oil-contaminated groundwater, dominated by iron reducing and methanogenic bacteria. Here carbon is abundant but Fe and P are scarce, and even resistant feldspars are rapidly colonized and destroyed if they contain these elements. Addition of feldspar chips containing trace apatite inclusions to laboratory microscosms accelerates BTEX biodegradatin and increases biomass. Chips of manufactured glass containing P are rapidly colonized, while similar glasses without P are barren. The subsurface distribution of microorganisms may in part be controlled by mineralogy, and an organism's ability to take advantage of mineral-bound nutrients. Conversely, mineral weathering may in part by a function of that mineral's nutritional potential, with microorganisms destroying only "beneficial" minerals.