Oxidation of soil organic carbon during an anoxic-oxic transition

摘要: Abstract Redox reactions of iron (Fe) can play an important role in controlling the stability and transformation organic carbon (OC) soils. However, there is limited knowledge about dynamics Fe OC soils during anoxic-oxic transitions, which are common temperate tropical biomes. In this study, we investigated fate a 5-day oxic incubation four pre-reduced (8 days anoxic) forest Up to 3.7% total was oxidized CO2, conjunction with oxidation 31–84% extractable Fe(II). lower than non-reduced control soils, indicating that recently anoxically-incubated support metabolism upon re-oxidation consistently Oxic negatively correlated fraction Fe-bound short-range-ordered (SRO) oxides. These results suggest association oxides—especially SRO oxides—can inhibit availability for oxidation. difference between controls could not be linked moderate changes mineral composition transition, importance longer-term oxides, as well other processes, regulating redox fluctuations. oxides should considered simulations biogeochemical cycling fluctuations, processes such anoxic response microbial community also need incorporated.