Dr Larry Flanagan, Board of Governors Research Chair and Professor , Department of Biological Sciences, University of Lethbridge presented a seminar on Thursday, September 15 2011 at 12.30 p.m. in the Wyatt Lecture Room (236 Earth Sciences Building), University of Alberta, Edmonton, Alberta.

Northern peatland ecosystems contain a large fraction of the global soil carbon stock, which has been suggested to be vulnerable to warming and drying associated with climate change. The fate of this vast peatland carbon stock depends on the relative responses of ecosystem photosynthesis and respiration to climate change-induced shifts in environmental conditions. In this seminar I will describe some recent studies of the controls on ecosystem photosynthesis and respiration in contrasting peatland ecosystems in northern Alberta, Canada, a region where peatlands occupy a significant fraction of the landscape. In particular, it will be highlighted how: (i) differences in the dominant plant functional type; (ii) interactions between water table depth and temperature; and (iii) ecosystem succession, can all strongly control the rate of net carbon sequestration in peatland ecosystems and influence their response to anticipated climate change.