Impacts of wildfire on soil erosion and fine-grained sediment dynamics in forested aquatic systems

点击翻译按钮获取中文摘要

Wildfire events have a significant and measurable impact on the sediment dynamics of forested catchments over wide spatial and temporal scales. This project will determine the response of sediment sources and evaluate sediment (mineral and organic) redistribution through aquatic systems due to wildfires in northern interior forest environments in Canada over contrasting spatial and temporal scales. A successful feasibility study in 2004 indicated that the sediment system in one of the study catchments to be investigated is responding to wildfire disturbance, as evidenced by changing sediment sources and sediment fluxes following a wildfire. The present project will apply a suite of integrated techniques to link contemporary responses to long term recovery from wildfire disturbance. Specifically, a field sampling and laboratory programme will be undertaken comprising three interlinked parts: (a) measurement and sampling on a hillslope unit before and after a prescribed (i.e. induced) burn, (b) a paired-catchment comparative study (i.e. a naturally burnt catchment and a nearby unburnt catchment with similar characteristics) and (c) a palaeolimnological study exploring changes in deposited sediment properties in lake catchments with known fire histories. Work will be undertaken in study areas of contrasting spatial scale (hillslope to catchment) and fire history (present, recent, decades and centuries). The results of these will be utilised to understand the response of catchments to fire in order to link short-term process knowledge with longer term data on sedimentary processes, in order to provide tools for investigating scenarios of potential impacts of burning in forests.