Search Results - "Carignan, Richard"

Seasonal methylmercury dynamics in water draining three beaver impoundments of varying age by Roy, Virginie, Amyot, Marc, Carignan, Richard

“…We monitored water chemistry including unfiltered and filtered total mercury (THg), total methylmercury (TMeHg) and redox‐sensitive species in three beaver…”
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Historical Perspective of Industrial Lead Emissions to the Atmosphere from a Canadian Smelter by Gallon, Céline, Tessier, André, Gobeil, Charles, Carignan, Richard

“…Dated sediment cores from four remote Canadian Shield headwater lakes, where atmospheric deposition has been the only input of anthropogenic Pb, situated along…”
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Beaver Ponds Increase Methylmercury Concentrations in Canadian Shield Streams along Vegetation and Pond-Age Gradients by Roy, Virginie, Amyot, Marc, Carignan, Richard

“…Beaver impoundments flood forested areas and may be important production sites for methylmercury (MeHg) because of the resulting enhanced microbial activity…”
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Can pelagic net heterotrophy account for carbon fluxes from eastern Canadian lakes? by Dubois, Kristal, Carignan, Richard, Veizer, Ján

“…Lakes worldwide are commonly oversaturated with CO 2, however the source of this CO 2 oversaturation is not well understood. To examine the magnitude of the C…”
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Seasonal methylmercury dynamics in water draining three beaver impoundments of varying age by ROY, Virginie, AMYOT, Marc, CARIGNAN, Richard

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Mercury concentrations in fish from forest harvesting and fire-impacted Canadian Boreal lakes compared using stable isotopes of nitrogen by Garcia, Edenise, Carignan, Richard

“…otal mercury (Hg)concentration was determined in several piscivorous and nonpiscivorous species of fish from 38 drainage lakes with clear‐cut, burnt, or…”
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Spatial Analysis of Production by Macrophytes, Phytoplankton and Epiphyton in a Large River System under Different Water-Level Conditions by Vis, Chantal, Hudon, Christiane, Carignan, Richard, Gagnon, Pierre

“…Relative contributions by macrophytes, epiphyton and phytoplankton to total primary production was estimated in a large (~300 km²) widening of the St. Lawrence…”
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Planktonic Production and Respiration in Oligotrophic Shield Lakes by Carignan, Richard, Planas, Dolors, Vis, Chantal

“…A precise oxygen method was used to measure primary production, community respiration and to determine the importance of exogenous organic carbon as an energy…”
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Thallium diagenesis in lacustrine sediments by Laforte, Lucie, Tessier, André, Gobeil, Charles, Carignan, Richard

“…Dated sediment cores and porewaters from two Canadian Shield lakes, located 40 km from Québec City (L. Tantaré) and 25 km downwind from an important smelter in…”
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Automated Determination of Carbon Dioxide, Oxygen, and Nitrogen Partial Pressures in Surface Waters by Carignan, Richard

“…An automated system capable of accurate determinations of O2, CO2, and N2partial pressures (p) in surface waters is described. The system is composed of a…”
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Seasonal and Inter-Annual Variations in Methyl Mercury Concentrations in Zooplankton from Boreal Lakes Impacted by Deforestation or Natural Forest Fires by Garcia, Edenise, Carignan, Richard, Lean, David R. S

“…We compared the effects of natural and anthropogenic watershed disturbances on methyl mercury (MeHg) concentration in bulk zooplankton from boreal Shield…”
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Geochemistry of trace metals associated with reduced sulfur in freshwater sediments by Huerta-Diaz, Miguel Angel, Tessier, André, Carignan, Richard

“…Porewater concentration profiles were determined for Fe, trace elements (As, Cd, Co, Cu, Mn, Ni, Pb, Zn), sulfide, SO 4 and pH in two Canadian Shield lakes…”
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Recognition of nutrient and light limitation in turbid mixed layers: Three approaches compared in the Parani floodplain (Argentina) by Carignan, Richard, Planas, Dolors

“…The potential difficulties of testing for nutrient limitation in turbid mixed layers are illustrated by comparing the outcome of three different approaches (in…”
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Decoupling of pelagic and littoral food webs in oligotrophic Canadian Shield lakes by Bertolo, Andrea, Carignan, Richard, Magnan, Pierre, Pinel-Alloul, Bernadette, Planas, Dolors, Garcia, Edenise

“…The importance of top-down effects of piscivorous fish on phytoplankton in natural oligotrophic lakes is still debated. In this study, we analyzed patterns in…”
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Soil Organic Sulfur Dynamics in a Coniferous Forest by Houle, Daniel, Carignan, Richard, Ouimet, Rock

“…Sulfate microbial immobilization and the mineralization of organic S were measured in vitro in soil horizons (LFH, Ae, Bhf, Bf and C) of the Lake Laflamme…”
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Metal Deposition Chronologies in Boreal Shield Lakes: Distinguishing Anthropogenic Signals from Diagenetic Effects by Carignan, Richard, Tessier, Andre, Rancourt, Lise

“…Accurate metal deposition records in lake sediments are necessary to assess their present human health and ecological risk and to evaluate the effects of…”
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A Field Study of Metal Toxicity and Accumulation by Benthic Invertebrates; Implications for the Acid-Volatile Sulfide (AVS) Model by Hare, Landis, Carignan, Richard, Herta-Diaz, Miguel A.

“…The toxicity and accumulation of Cd from sediment by benthic invertebrates was measured along a Cd gradient created in nature. The efficacy of acid-volatile…”
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Macroinvertebrates on Eichhornia crassipes roots in two lakes of the Paraná River floodplain by POI DE NEIFF, A, CARIGNAN, R

“…Changes in the abundance, biomass and in the relativeproportions of functional feeding groups ofmacroinvertebrates were studied for 17 months duringlow and…”
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Use of X-Ray Images and a Contrasting Agent to Study the Behavior of Animals in Soft Sediments by Charbonneau, Patrick, Hare, Landis, Carignan, Richard

“…We developed a means of observing and recording the burrowing behavior of animals in soft sediments by using X-ray images. The poor contrast between animal…”
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Metal Deposition Chronologies in Boreal Shield Lakes: Distinguishing Anthropogenic Signals from Diagenetic Effects by Carignan, Richard, Tessier, André, Rancourt, Lise

“…Accurate metal deposition records in lake sediments are necessary to assess their present human health and ecological risk and to evaluate the effects of…”
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