2 ǀ The soil chemistry of IRON toxicity
The following is a summary of the changes in soil chemistry following
submergence for lowland rice, taken from Kirk (2004). When a soil is
submerged, air is excluded and the soil quickly becomes anoxic. Microbes
must then use alternative end electron acceptors in oxidizing organic
compounds for their energy needs. This proceeds roughly in the sequence
predicted by thermodynamics: