A5085979996- Marine and coastal ecosystems
- Isotope Analysis in Ecology
- Climate change and permafrost
- Arctic and Antarctic ice dynamics
- Geology and Paleoclimatology Research
- Aquatic Ecosystems and Phytoplankton Dynamics
- Microbial Community Ecology and Physiology
- Fish Ecology and Management Studies
- Polar Research and Ecology
- Cryospheric studies and observations
- Methane Hydrates and Related Phenomena
- Environmental DNA in Biodiversity Studies
- Marine Biology and Ecology Research
- Aquatic Invertebrate Ecology and Behavior
- Peatlands and Wetlands Ecology
- Indigenous Studies and Ecology
- Marine Bivalve and Aquaculture Studies
- Marine animal studies overview
- Biocrusts and Microbial Ecology
- Marine and fisheries research
- Atmospheric chemistry and aerosols
- Marine and coastal plant biology
- Environmental Toxicology and Ecotoxicology
- Tree-ring climate responses
- Genomics and Phylogenetic Studies
Université du Québec à Chicoutimi
2015-2024
Center for Northern Studies
2015-2024
Université Laval
2014-2023
Université de Montréal
2016-2023
Université du Québec à Montréal
2023
Ecological Society of America
2020
John Wiley & Sons (United States)
2020
GDG Environnement
2018
University of Jyväskylä
2010-2016
Université du Québec
2010
Abstract. The Arctic is a water-rich region, with freshwater systems covering about 16 % of the northern permafrost landscape. Permafrost thaw creates new ecosystems, while at same time modifying existing lakes, streams, and rivers that are impacted by thaw. Here, we describe current state knowledge regarding how affects lentic (still) lotic (moving) systems, exploring effects both thermokarst (thawing collapse ice-rich permafrost) deepening active layer (the surface soil thaws refreezes...
Abstract Interactions between climate change and UV radiation are having strong effects on aquatic ecosystems due to feedback temperature, radiation, greenhouse gas concentration. Higher air temperatures incoming solar increasing the surface water of lakes oceans, with many large warming at twice rate regional temperatures. Warmer oceans changing habitats species composition marine ecosystems. For some, such as corals, may become too high. Temperature differences deep waters becoming...
Abstract Climate change and permafrost thaw are unlocking the vast storage of organic carbon held in northern frozen soils. Here, we evaluated effects thawing ice‐rich on dissolved matter (DOM) freshwaters by optical analysis 253 ponds across circumpolar North. For a subset waters subarctic Quebec, also quantified contribution terrestrial sources to DOM pool stable isotopes. The measurements showed higher proportion lower algal affected permafrost. composition was largely dominated (mean...
This review provides a synthesis of limnological data and conclusions from studies on ponds small lakes at our research sites in Subarctic Arctic Canada, Alaska, northern Scandinavia, Greenland. Many these water bodies contain large standing stocks benthic microbial mats that grow relatively nutrient-rich conditions, while the overlying column is nutrient-poor supports only low concentrations phytoplankton. Zooplankton biomass can, however, be substantial supported by grazing as well...
Abstract The ice‐cover period in lakes is increasingly recognized for its distinct combination of physical and biological phenomena ecological relevance. Knowledge gaps exist where research areas hydrodynamics, biogeochemistry biology intersect. For example, density‐driven circulation under ice coincides with an expansion the anoxic zone, but abiotic biotic controls on oxygen depletion have not been disentangled, while heterotrophic microorganisms migrating phytoplankton often thrive at...
Summary 1. Shallow lakes and ponds are a major component of the northern landscape often contain high zooplankton biomass despite clear waters that poor in phytoplankton. 2. In this study we quantified food sources feeding rates shallow two contrasting high‐latitude biomes: subarctic forest tundra (Kuujjuarapik, Quebec) arctic polar desert (Resolute, Nunavut). Five substrate types were tested (beads, bacteria, picophytoplankton, filamentous plankton microbial mats). Special attention was...
We addressed the extent to which autochthonous and allochthonous carbon sources contribute zooplankton diet throughout year in oligotrophic subarctic Lake Saanajärvi. Optical measures of dissolved organic matter (DOM) indicated high water discharge associated terrestrial DOM during winter low inputs summer. Bulk particulate (POM) showed δ 13 C values consistent with DOM. The most positive POM (−27‰) occurred winter, when heterotrophic bacteria nanoflagellates peaked abundance; isotopically...
While many laboratory and field studies show that zooplankton are negatively affected when exposed to high intensities of ultraviolet radiation (UVR), most also indicate well adapted cope with large variations in their UVR exposure the pelagic zone lakes. The response mechanisms diverse efficient may explain success richness freshwater optically variable waters. no single behavioural or physiological protection mechanism seems be superior, while several unexplained contradictory patterns...
Shortening winter ice-cover duration in lakes highlights an urgent need for research focused on under-ice ecosystem dynamics and their contributions to whole-ecosystem processes. Low temperature, reduced light consequent changes autotrophic heterotrophic resources alter the diet long-lived consumers, with consequences metabolism winter. We show a survival experiment that copepod Leptodiaptomus minutus boreal lake does not survive five months under ice without food. then report seasonal...
Northern lakes are ice-covered for a large part of the year, yet our understanding microbial diversity and activity during winter lags behind that ice-free period. In this study, we investigated under-ice metabolism Verrucomicrobia in seasonally temperate boreal regions Quebec, Canada using 16S rRNA sequencing, metagenomics metatranscriptomics. Verrucomicrobia, particularly V1, V3 V4 subdivisions, were abundant periods. A genomes reconstructed from Quebec lake metagenomes. Several associated...
Abstract Winter is an important season for many limnological processes, which can range from biogeochemical transformations to ecological interactions. Interest in the structure and function of lake ecosystems under ice on rise. Although limnologists working at polar latitudes have a long history winter work, required knowledge successfully sample conditions not widely available relatively few receive formal training. In particular, deployment operation equipment below 0°C temperatures pose...
Significance Freshwater ice is being lost at an accelerating rate with global warming. Yet the ecological implications of shortening ice-covered seasons remain largely unexplored due to a historical lack freshwater research in winter. We provide innovative experimental study that realistically reproduces warming effects on timing onset address consequences for lake food webs. find later ice-on sustains photosynthesis longer, permitting greater accumulation high-quality fat reserves primary...
Abstract Millions of lakes worldwide are distributed at latitudes or elevations resulting in the formation lake ice during winter. Lake affects transfer energy, heat, light, and material between their surroundings creating an environment dramatically different from open‐water conditions. While this fundamental restructuring leads to distinct gradients ions, dissolved gases, nutrients throughout water column, surprisingly little is known about effects on ecosystem processes food webs,...
In the subarctic region, climate warming and permafrost thaw are leading to emergence of ponds an increase in mobility catchment carbon. As carbon terrestrial origin is increasing freshwaters resource pool supporting their microbial communities metabolism changing, with consequences overall aquatic productivity. By sampling different water bodies for a one complete year we show how algal compounds vary range differential organic quality linked bacterial community composition. We that...
Abstract Accumulation of carotenoid pigments in copepods has often been described as a plastic adaptation providing photoprotection against ultraviolet radiation (UVR). However, reports seasonal maxima winter, when UVR is low, challenge the proposed driving role UVR. Therefore, we here evaluate mechanistic connection between and pattern copepod pigmentation. We assessed carotenoids, fatty acid content reproduction Leptodiaptomus minutus along with exposure, water temperature, phytoplankton...
Abstract Around 50% of the world's lakes freeze seasonally, but duration ice‐cover is shortening each year and this likely to have broad limnological consequences. We sampled freshwater ice underlying water in 19 boreal polar evaluate whether lake contains an inoculum algae, nutrients, carbon that may contribute ecosystem productivity. Boreal Arctic differed (6 vs. >10 months), thickness (70 190 cm), quality (predominantly snow black ice), all lakes, there were consistent differences...
ABSTRACT Teleost gill mucus has a highly diverse microbiota, which plays an essential role in the host’s fitness and is greatly influenced by environment. Arctic char ( Salvelinus alpinus ), salmonid well adapted to northern conditions, faces multiple stressors Arctic, including water chemistry modifications, that could negatively impact microbiota dynamics related health. In context of increasing environmental disturbances, we aimed characterize taxonomic distribution transcriptionally...
Abstract Arctic freshwaters are facing multiple environmental pressures, including rapid climate change and increasing land___use activities. Freshwater plankton assemblages expected to reflect the effects of these stressors through shifts in species distributions changes biodiversity. These may occur rapidly due short generation times high dispersal capabilities both phyto___ zooplankton. Spatial patterns contemporary trends diversity throughout circumpolar region were assessed using data...
Shallow high‐latitude lakes and ponds are usually characterized by an oligotrophic water column overlying a biomass‐rich, highly productive benthos. Their pelagic food webs often contain abundant zooplankton but the importance of benthic organic carbon versus seston as their sources has been little explored. Our objectives were to measure δ 13 C 15 N isotopic signatures particulate matter (POM) in shallow bodies northern Canada determine relative transfer this material other aquatic...
1. Subarctic ponds are seasonal aquatic habitats subject to short summers but often have surprisingly numerous planktonic consumers relative phytoplankton productivity. Because subarctic low pelagic productivity a high biomass of benthic algae, we hypothesised that mats provide complementary and important food source for the zooplankton. To test this, used combination fatty acid stable isotope analyses evaluate nutritional content their contributions diets crustacean zooplankton in 10...
Summary Generalist fish species commonly act as important links between littoral and pelagic habitats food‐web compartments in lakes. However, diet habitat may depend significantly on seasonal availability of, qualitative differences between, prey size. Despite increasing interest dynamics, little is known about the changes in, or trophic pathways supporting generalist high‐latitude We used stomach contents together with analyses of stable carbon nitrogen isotopes fatty acids to study winter...