K.J. Dinsmore, M.F. Billett, M. Wallin, M.S Johnson, K. Bishop, J Pumpanen
Proceedings of the 14th International Peat Congress
aquatic-carbon, co2, doc, export, storm-flow
Dinsmore et al 2012: Role of High-Flow Extremes in Aquatic Carbon Export From Peatlands
Theme X. Peatland carbon budgets and greenhouse gas (GHG) fluxes
Peatland streams have repeatedly been shown to be highly supersaturated in gaseous carbon and export significant amounts of both dissolved (DOC) and particulate (POC) organic carbon. Export is strongly bias towards high flow events, which may become more frequent under predicted climate change scenarios. Here we bring together 2 separate analyses of the role of high-flow ‘extremes’ on (i) DOC export, and (ii) CO2 export. Based on 30-day moving Q5 thresholds, we show that in the 5% of time with highest flows between 33-47% of DOC and 6-33% of CO2 is lost. This demonstrates the disproportional impact of high flow events on C export from peatland aquatic systems.