Ecological controls on wetland sediment records: late quaternary to present

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Wetlands represent important sedimentary terrestrial archives of environmental change that have undergone phases of decline and resurgence in research because of an incomplete understanding of the wetland ecosystem. This is most apparent in Canada which contains more wetland than any other country, and other regions outside Europe and Russia where most of the information on wetland sedimentary archives exists. While most of research has tended to focus on detecting climate signals in lake and wetland sedimentary records, we want to understand how the ecology of wetlands (i.e. physical, hydrological, geochemical and biotic) controls the sediment record across a variety of environmental gradients, ecosystem types, and biotic communities that range in spatial scale (microsite to regional watersheds) and temporal scales (present-day to long-term changes during the late Quaternary) because signals preserved in the record can be both ecological and climatic.  Our research focuses on understanding what the rates, drivers, and developmental pathways are that lead to wetlands being what they are today and will be in the future. We have selected wetlands with specialized ecology such as kettle holes and metal-rich "cupriferous" wetlands so that ecological signals might clearly differentiated from climatic signals in the sediment record.  Also, wetlands will be studied in NW Ontario, a region known to have experienced major climate shifts in the Holocene in order to compare ecological and climate signals in the sediment/peat records.   We study a range of physical (ie. bulk density, decomposition, ash content, charcoal), biotic (ie. pollen and plant macrofossils, Protozoa), and geochemical (C, N, isotopes) proxy indicators in the sediment record. Wetland ecosystems provide numerous benefits to human health, society, livelihoods, and economy and as such information collected during this research program will provide information of interest to wetland managers, government regulators and policy makers, conservationists, the private sector, and economists.  Current relevant environmental issues of interest include global warming, flood protection, landscape restoration, and wetland ecotechnology.