ena-STUDY-UPPSALA UNIVERSITET-01-05-2018-11:35:09:238-202
Carbon utilization of peat soils at low temperatures
Despite low temperatures and frozen conditions, low temperature biogeochemical processes in northern peatlands are crucial for the long-term net ecosystem carbon balance. We hypothesized that peat soil microorganisms have the capacity to utilize simple C substrates sustaining both catabolic and anabolic processes in frozen peat soils. To evaluate this hypothesis, we added 13C- glucose to laboratory incubations of boreal peat soil at -5, -3, 4, and 9°C. The microbial catabolic and anabolic utilization of the substrate was tracked by following the transformation rates of the 13C-glucose to 13C-CO2, 13C water-soluble compounds and the incorporation of 13C into phospholipid fatty acids (PLFAs). This allowed the evaluation of the impact of below zero temperatures/soil freezing on metabolic rates and the validation of the activity of the microbial community under typical winter peat soil temperatures.
Despite low temperatures and frozen conditions, low temperature biogeochemical processes in northern peatlands are crucial for the long-term net ecosystem carbon balance. We hypothesized that peat soil microorganisms have the capacity to utilize simple C substrates sustaining both catabolic and anabolic processes in frozen peat soils. To evaluate this hypothesis, we added 13C- glucose to laboratory incubations of boreal peat soil at -5, -3, 4, and 9°C. The microbial catabolic and anabolic utilization of the substrate was tracked by following the transformation rates of the 13C-glucose to 13C-CO2, 13C water-soluble compounds and the incorporation of 13C into phospholipid fatty acids (PLFAs). This allowed the evaluation of the impact of below zero temperatures/soil freezing on metabolic rates and the validation of the activity of the microbial community under typical winter peat soil temperatures.