Research in Dr. Quinlan’s Lab

Aquatic Ecology, Limnology, Paleolimnology

Freshwater aquatic ecosystems are currently affected by multiple anthropogenic stressors. These stressors include recent climate change, acid rain, contaminant pollution, nutrient enrichment (eutrophication), land-use change (vegetation clearance for agriculture, urbanization etc), reservoir/impoundment construction and exotic species invasions, to name a few. Environmental monitoring programs of aquatic systems that are based on an ecological perspective (simultaneous monitoring of biological, chemical and physical variables) are relatively new as early programs were designed to monitor the impacts of acidic deposition in the 1970s. As a consequence, long-term ecological datasets (>20 yrs data) are extremely rare and located primarily in geographic regions downwind of major acidic deposition (north-eastern USA and central Ontario region of Canada). This lack of long-term ecological data presents difficulties in answering some basic questions that are important to consider when assessing the ecological impacts of stressors: What are ‘natural’ or pre-disturbance conditions of the ecosystem? What is the natural variability of the system? It is possible to obtain this long-term data through proxy methods, such as through examination of paleoecological data archived in lake and pond sediments. Sediments are natural archives of ecological data, with a host of physical, chemical, and biological variables providing insights into past aquatic ecosystem conditions.

My area of research specialization involves examining the chitinous subfossil remains of midges (Diptera: Chironomidae; “chironomids”) in lake and pond sediments, to generate paleoecological assessments of past aquatic ecosystem changes. However, my research interests are broad, as I am interested in a breadth of paleoecological and ecological methods (including “real-time” environmental monitoring) and indicators (including algae (e.g. diatoms) and zooplankton (e.g. Daphnia and Chaoborus)) to examine aquatic ecosystem responses to a variety of human-induced stressors. My research interests, and the projects undertaken by my graduate students, encompass numerous types of aquatic systems, ranging from embayments of the Laurentian Great Lakes in southern Canada to shallow ponds in the northern tip of the Canadian High Arctic.

Recent publications and submitted manuscripts:

Quinlan, R & Smol, JP, accepted. The living Chaoborus assemblage can be assessed using subfossil mandibles. Freshwater Biology

Quinlan, R & Smol, JP. 2010. The use of Chaoborus subfossil mandibles in the development of paleoecological inference models of hypolimnetic oxygen. Journal of Paleolimnology 44: 43-50.

Paterson, AM, Quinlan, R, Clark, BJ & Smol, JP. 2009. Assessing hypolimnetic oxygen concentrations in Canadian Shield lakes: deriving management benchmarks using two methods. Lake and Reservoir Management 25: 313-322

Quinlan, R, Hall, RI, Paterson, AM, Cumming, BF and Smol, JP.  2008.  Long-term assessments of ecological effects of anthropogenic stressors on aquatic ecosystems from paleoecological analyses: challenges to traditional perspectives of lake management.  Canadian Journal of Fisheries and Aquatic Sciences 65:  933-944.

Brodersen, KP & Quinlan, R. 2006. Midges as paleoindicators of lake productivity, eutrophication and hypolimnetic oxygen. Quaternary Science Reviews 25: 1995-2012.

Quinlan, R, Douglas, MSV & Smol, JP, 2005. Food web changes in Arctic ecosystems related to climate warming. Global Change Biology 11: 1381-1386.

Current graduate students in Dr. Quinlan’s lab

Dr. Quinlan is on sabbatical for 2010-2011, and will not be accepting new students until May or September 2011 entry.

Raymond Biastock, PhD Candidate

The examination of patterns in the limnological and biological differences of Arctic lakes and ponds as a function of their position in the landscape.

Using a hierarchical classification of Arctic aquatic systems to select study areas, I will sample the physical, chemical, and biological traits of lakes and ponds. I aim to determine the relative influences of local, watershed-specific factors vs. regional, climate-mediated factors on aquatic ecosystem functioning and structure. With estimates of the relative importance of regional-scale factors on freshwater ecosystems, it would be possible to estimate the relative effects of predicted future climate warming on Arctic lake, pond and river ecosystems.

Christopher Luszczek, PhD Candidate

An assessment of the composition, structure and variation of benthic communities in Canadian Arctic lakes and ponds

I will examine the variables responsible for structuring aquatic macroinvertebrate communities Across mainland Nunavut. I will determine whether community composition primarily represents habitat-scale variables (such as littoral substrate) or landscape-scale variables (such as climate, surrounding watershed vegetation and geology). As such, these research findings have important implications for rapid ecosystem assessment and creating biomonitoring programs. This research will hopefully provide valuable information for better understanding ecosystem functioning in these sparsely studied Arctic systems

Andrew Medeiros, PhD Candidate

A biogeographic examination of climate driven impacts to Arctic aquatic systems

http://www.inuk.ca

Kristin Wazbinski, MSc Candidate

Paleolimnological analysis of nutrient enrichment for criteria development in New Jersey and New York lakes

Kristin will be assessing the impact of anthropogenic stressors in freshwater lakes in the north eastern part of the United States (New Jersey and New York State), using paleolimnological approaches (stratigraphic analyses of chironomid-inferred changes in hypolimnetic anoxia, Daphnia inferred changes in fish abundances). By determining pre-disturbance conditions via paleolimnology, it is possible to evaluate remediation goals by State Agencies tasked with evaluating and maintaining water quality in State freshwater resources.

Past students in Dr. Quinlan’s lab

Fatemeh Panahi Dorcheh, MSc, September 2007

Inferring past fish abundance from Daphnia ephippia size in south-central Ontario lakes

Fatemeh processed surficial intervals of sediment cores from 50 lakes located in the Sudbury and Muskoka-Haliburton regions of south-central Ontario. An inference model was developed using the dorsal length of subfossil Daphnia ephippia as a proxy indicator of fish abundance (expressed as planktivorous fish CPUE).

Armin Namayandeh, MSc, January 2009

Diversity and distribution of benthic invertebrates in lakes and ponds of Nunavut, Canada

Armin examined patterns in benthic macroinvertebrates in a suite of lakes and ponds in the vicinity of Rankin Inlet and Iqaluit, Nunavut. Shoreline samples of benthic invertebrates were collected using 500-µm mesh D-nets, and community composition of these samples was analyzed using multivariate statistics (e.g. Redundancy Analysis, RDA) to determine which environmental gradients are primarily responsible for structuring macroinvertebrate communities in these water bodies.

Danielle Rodé, MSc, August 2009

A paleolimnological approach to assessing the sustainability of the Lake Simcoe cold-water fishery based on historic habitat quality and fish abundances

Danielle used a paleolimnological approach to determine how hypolimnetic dissolved oxygen concentrations and fish abundances have changed in Lake Simcoe since European settlement. Historic hypolimnetic oxygen levels were quantified using a chironomid-based inference model. Fish abundances were reconstructed using subfossil Daphnia ephippia as indicators of past planktivorous predation pressure (as a proxy for fish abundance). The purpose of this research is to determine if current rehabilitation goals to remediate Lake Simcoe water quality represent natural historic conditions of the lake system.

Sarah Payne – Honours thesis, BIOL 4000 8.0, April 2010

Effects of a 2007 pesticide influx on the macroinvertebrate community of Spencer Creek, Dundas, ON from 2008-2009

Luana Sciullo – Honours thesis, BIOL 4000 8.0, April 2007

Reconstructing the abundance and predation intensity of planktivorous fish in Leech Lake, Ontario, using historical changes in Daphnia ephippia as a paleoindicator

Christine Gibson – Honours thesis, BIOL 4000 8.0, August 2006

Examining the relationship between chironomid communities and environmental gradients of Wapusk National Park, northern Manitoba

Jan Moryk – Honours thesis, BIOL 4000 8.0, August 2006

Changes in zooplankton communities in Lake Opeongo, Algonquin Park, in response to changes in summer water temperatures

Mark Townsend – Honours thesis, BIOL 4000 3.0, December 2005

A comparison of different methodologies designed to assess ecological recovery in freshwater ecosystems