Implications of varying ice and nutrient regimes on the hydroecology of cold regions lakes

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Northern freshwater ecosystems are undergoing rapid environmental change in response to impacts from the natural and human-induced stressors, including changes in the climate. These impacts, whether direct or indirect, have the potential to alter food-webs, energy flows, species and productivity relationships. Cold-region lakes are especially sensitive to a changing climate since even small changes in environmental conditions such snow- and ice-cover, can have significant cascading impacts on ecological processes and related outcomes. Currently, there is a limited understanding of how northern freshwater ecosystems are affected by changes in the climate system and in particular, the controlling influences of changing winter cryospheric conditions. My research project directly addresses this significant knowledge gap by examining the importance of a changing ice-cover on under-ice and subsequent open-water quality, and related seasonal plankton dynamics and productivity relationships. ******Blue-green algae blooms are a growing concern for many lakes in Western Canada. Such blooms become prevalent when there is an excess of nutrients, and an increase in photosynthesis occurs due to hot and sunny weather. These blooms are of concern to the public as they can cause eye and skin irritation, and if ingested can cause humans, pets, livestock and wildlife to become ill. Further research into the connection between under-ice cover lake ecology and the subsequent development of plankton communities, such as blue-green algae, will provide a deeper understanding of how changing ice conditions affects the development of such noxious outbreaks. ******In this project, I will be using a combination of controlled experiments, mimicking the condition of freshwater lakes, to examine the role of various ice-cover conditions including, timing, quantity, quality and duration on under-ice and subsequent open-water ecology. Samples will also be taken from lakes in Alberta which represent a range of nutrient and ice-cover conditions. Additional experiments will be conducted at the University of Calgary Aquatic Experimental Facility to evaluate the impacts of a changing ice-cover on water quality and aquatic food-web structure. ******My research will provide new knowledge and insights in identifying and quantifying the importance of changing ice-cover conditions on the ecology of cold-region lakes. In addition, the research will generate new data that are critical to informing the development of improved water quality modelling/prediction systems. Such prediction systems play an increasingly important role in supporting government decision-making processes related to lake monitoring program design, integrated basin management and cumulative effects assessment, under present and future climate scenarios.