Area of Research
"A lake is the landscape's most beautiful and expressive feature. It is the earth's eye, looking into which the beholder measures the depth of his own nature."
Henry David Thoreau
Global water resources are under threat. Both water quantity and quality is being reduced by human activities and climate change. The Lake and Reservoir System (LARS) Research Facility uses paleoindicators (i.e. biological, chemical and physical `fingerprints' of past environmental conditions) preserved in lake sediments (mud) to determine past water quantity and quality, and to provide information about pre-human conditions, natural variability and the mechanisms causing changes. Sediments deposited in lakes and other aquatic environments, including wetlands and estuaries, often form a continuous record and are, therefore, an excellent archive of past and present water quantity and quality. Lake sediments are deposited at the bottom of lakes year after year, layer after layer.
Because it is possible to determine the age of different layers of sediment, we can determine the age of different layers of sediment, we can determine, sing the `fingerprints' preserved in the sediments, what water conditions were like at particular times and for what durations. Was it colder? Were there less or more nutrients in the water? Were there more metals? Was the lake shallower? Was it more saline? Was the lake more acidic? By answering these questions, we can address many environmental issues. For example, were there more droughts than are documented for the last 100 years during previous centuries and millennia in drought-sensitive areas such as California and southern Alberta? What will the consequences of warmer temperatures, predicted for the future, to water quality? Why have nutrients in many alpine lakes increased in the recent past? Why are toxic algal blooms occurring in some lakes, when they haven't been documented in the past and policies have been implemented to improve water quality?
At the LARS Research Facility our research has focused on using paleoindicators, including diatoms, pollen, chironomids, sedimentological changes and biochemical changes, to determine past water quantity and quality. Our focus has been on using diatoms to determine past lake-water conditions. Diatoms are microscopic (smaller than the diameter of a human hair) algae that are characterized by a cell wall composed of opaline silica. These tiny organisms carry messages from the past about water quantity and quality. Diatoms are one of the most widely and successfully used paleoindicators in studies of global environmental change because they are abundant in most aquatic environments, are ecologically diverse, and are particularly sensitive to environmental change. As well, the siliceous cell walls of diatoms are taxonomically unique and well-preserved in a variety of aquatic sediments. Finally, ecologically and statistically significant relationships have been quantified between diatom community composition and environmental variables, allowing for quantitative estimates of past environmental variables.
The LARS Research Facility in dedicated to interdisciplinary research and collaborative science. The team comprises people with research backgrounds in Geography, Biology, Geology and Environmental Science and includes undergraduate students, graduate students and post-doctoral fellows. We collaborate with researchers from around the world and are involved in a wide range of projects.
