See more from this Division: S10 Wetland Soils
See more from this Session: Wetland Soil Carbon Pools and Fluxes (includes Graduate Student Competition)
Abstract:
Compared to the anoxic sample pretreatment, oxic pretreatment resulted in a reduced contribution of O/N-alkyl-C to the SOM pool of the samples. The alkyl-C/O-alkyl C ratio was strongly increased, indicating increased microbial degradation. Additionally, the ratio (galactose + mannose)/(arabinose + xylose) (GM/AX) increased, indicating an increased contribution of microbial sugars and a reduced contribution of plant-derived sugars. Results of a laboratory incubation of the samples under oxic conditions at 20°C for different time intervals ranging from 1.5 to 96 h showed a consistent decrease of the soil mass, the C/N ratio, and the amount of total sugar, particularly of glucose. Concomitantly, the alkyl-C/O-alkyl C ratio and the GM/AX ratio increased. The results indicate a rapid microbial degradation of organic matter in anoxic peat after access of oxygen. Appropriate sampling and processing of such samples should consider this by preventing any access of oxygen during the entire sample pretreatment procedure.
See more from this Division: S10 Wetland Soils
See more from this Session: Wetland Soil Carbon Pools and Fluxes (includes Graduate Student Competition)