Oscillations in soil bacterial redox reactions.

Colloid mobilization during soil iron redox oscillations.

In redox-dynamic soils, iron reduction-oxidation events may initiate wide shifts in the concentration of colloidal and dissolved material because of either Fe mineral dissolution or pH shifts associated with Fe oxidation state changes. This can have profound effects on the mobilization of organic and metal constituents. We conducted laboratory studies of colloid dynamics in a Hawaiian soil subj...

An investigation into the reactions of biochar in soil

Interactions between biochar, soil, microbes, and plant roots may occur within a short period of time after application to the soil. The extent, rates, and implications of these interactions, however, are far from understood. This review describes the properties of biochars and suggests possible reactions that may occur after the addition of biochars to soil. These include dissolution–precipita...

The Electrochemical Properties of Biochars and How They Affect Soil Redox Properties and Processes

Biochars are complex heterogeneous materials that consist of mineral phases, amorphous C, graphitic C, and labile organic molecules, many of which can be either electron donors or acceptors when placed in soil. Biochar is a reductant, but its electrical OPEN ACCESS Agronomy 2015, 5 323 and electrochemical properties are a function of both the temperature of production and the concentration and ...

Nitrate Remeidation by Iron Redox Reactions in Soils

The chemistry of pedogenic thresholds

Pedogenesis can be slow or fast depending on the internal chemical response to environmental forcing factors. When a shift in the external environment does not produce any pedogenic change even though one is expected, the soil is said to be in a state of pedogenic inertia. In contrast, soil properties sometimes change suddenly and irreversibly in a threshold response to external stimuli or inte...