A new model of long-term, coupled dynamics of carbon and water in northern peatlands

We present a new model that simulates coupled carbon and water dynamics of northern peatlands at an annual time step over time scales of decades to millennia. The Holocene Peatland Model (HPM) simulates peatland carbon and water dynamics as the net consequence of several interacting processes: (1) above- and below-ground vegetation NPP and litter production for bryophytes, woody and herbaceous plants; (2) aerobic and anaerobic litter/peat decomposition down the peat profile; (3) the dependence of peat physical and hydraulic properties on peat composition and degree of humification; and (4) peatland annual water balance, water table depth, and unsaturated zone water content. In this initial analysis, a simulation of long- term peat accumulation is compared against peat core data from a northern peatland in North America. The sensitivity of peatland carbon and water dynamics to climate variability are explored.