Who We Are

The Dorset Environmental Science Centre is an environmental science facility consisting of government, university and non-governmental partners. Through monitoring and research, we collaborate on a broad spectrum of topics related to Ontario's inland aquatic ecosystems and the watersheds in which they reside.

Mission Statement

To investigate the effects of multiple stressors, including climate change, on water quality and quantity in Ontario’s inland aquatic ecosystems and sustain the functions and services that these systems provide.

History of the Dorset Environmental Science Centre

The Dorset Environmental Science Centre (DESC) is located in the heart of Ontario’s cottage-country, near the southern boundary of the Precambrian Shield, approximately 200 km north of Toronto. The DESC serves as the Ontario Ministry of the Environment, Conservation and Parks centre of scientific expertise on environmental issues affecting Ontario’s inland lakes. Through multi-sector partnerships, Ministry staff (and a variety of non-Ministry collaborators) monitor lake condition and conduct research on environmental issues impacting inland lakes: lakeshore development (nutrient enrichment), atmospheric deposition of toxics (e.g., acid rain), global climate change, mercury contamination, and invading species.

DESC was established in the mid-1970s in response to the need for scientifically defensible regulations to limit cottage development. Through atmospheric, terrestrial and aquatic-ecosystem monitoring programs, DESC scientists contributed to the research on acid rain in Ontario and subsequently recognized the importance of long-range atmospheric transport of acid emissions. Through the late 1970s and 1980s, DESC monitoring and research on the ecological impacts of acid rain contributed to the development of environmental regulations for reducing sulphur emissions across North America.

Beginning in the mid-1990s, research at DESC evolved to focus on the multiple and interacting environmental stressors that affect lakes. This new integrated scientific approach has enabled DESC scientists to better understand mechanisms driving lake responses to human activities. For example, we have learned that sulphur-containing compounds are now released into water bodies when rains follow extended periods of drought. These compounds re-acidify water bodies and have slowed anticipated recovery from acid rain; however, questions remain regarding the influence of climate warming on the frequency of droughts and subsequent re-acidification events.

DESC scientists have also learned that the water quality and ecology of Ontario’s inland lakes reflect watershed geology and vegetation, but human settlement, land-use, climate, colonization by non-native species, and chemical pollutants modify these influences. Ongoing research on these interacting stressors has uncovered a number of surprises. For example, calcium concentrations in Shield lakes are decreasing. Decades of acid loading, coupled with logging, have depleted watershed stores of calcium, and further decreases are predicted. Laboratory studies at DESC have shown that calcium loss is an important stressor for many aquatic species, especially when less calcium is combined with lower food availability and the warmer temperatures that are predicted in future climate change scenarios. Phosphorus, an important nutrient in lakes, is also decreasing. Less phosphorus means a decrease in algal production, but (surprisingly) a decrease in phosphorus can increase the frequency of short-term population explosions of some species (i.e., algal blooms).

Over the years, DESC study lakes and streams have changed. Periods of relative stability have been punctuated by rapid and dramatic shifts in condition. Significant biological changes have been observed in most lakes, and many of these changes are linked to climate. For example, the relative densities of some types of algae have increased over the years, and changes in shallow-water invertebrate communities have also been observed. These coherent multi-lake patterns suggest that regional factors, such as climate, are affecting the biota of Ontario’s inland lakes.

Collectively, observations made by Ministry and partner-agency staff at DESC indicate that climate change is affecting Ontario’s lakes now. Because of the complex interplay of multiple factors, individual lake responses are difficult to predict. Consequently DESC monitoring and reporting efforts no longer focus on single stressors, but now focus on the interacting impacts of multiple stressors. This multi-faceted monitoring and research approach is a model for DESC’s future direction: emerging issues will be detected early, before damage is irreversible, and this new knowledge will provide the foundation to develop scientifically sound policies that protect our inland waters.