Concepts

Microbial process where methane is oxidized under anoxic conditions, often coupled to reduction of alternative electron acceptors

The oxidation of ammonia to nitrate via nitrite, linking nitrogenous organic matter remineralization to nitrogen loss processes in the microbial N-cycle

Chemical and physical breakdown of sedimentary shale rocks through interactions with water, atmospheric gases, and biological processes

Spatial organization of aerobic and anaerobic zones based on dissolved oxygen availability that controls biogeochemical reactions

Microbial reduction of sulfate coupled to organic matter oxidation in anoxic environments resulting in formation of low solubility sulfide minerals

The cycling of iron between different chemical forms including soluble ferrous iron (Fe(II)) and ferric iron (Fe(III)) based on oxygen availability

Formation of coordination complexes between Fe(II) ions and natural organic matter ligands

Rate laws governing the chemical breakdown of primary minerals as functions of temperature, pH, and saturation state

The transfer of CO2 from water to atmosphere through gas exchange at the air-water interface

Distribution of carbon between different reservoirs including atmosphere, subsurface, and exported dissolved phases during weathering processes

Changes in rock porosity and permeability due to mineral dissolution and precipitation reactions during weathering

The reducing or oxidizing capacity of a system that determines a river or floodplain's ability to break down waste products and recycle carbon and nutrients