A climate change scenario: the effect of an extreme storm event on carbon and nutrient mobilisation in peatlands
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Peatlands are one of the world’s largest carbon reservoirs. They are also significant carbon sources to the atmosphere, streams and rivers. One mechanism for mobilizing old water and associated solutes is translatory flow. This is where the pressure exerted by rainfall at the surface of the water table produces a pressure gradient across the aquifer causing older water to be discharged at the aquifer boundaries. This project investigates the effects of storm events on dissolved organic carbon (DOC) and ion mobilisation from a peatland in the Fichtelgebirge. The aim is to determine if physical hydrological processes such as translatory flow influence water and chemical mobilisation dynamics during events. During the beginning of July 2014 a storm event occurred with approximately 70 mm of precipitation within one week. This corresponds to nearly 7 % of the annual precipitation. As the storm event followed a period of drought, this is an example an extreme event which are predicted to increase in the future in the face of climate change. We have monitored in high resolution water levels and concentrations of biogeochemically relevant elements (hourly) and DOC (every 15 min.) at the peatland boundary (trench). In addition radon was measured continuously during the storm event to distinguish between mobilisation of old and new water.