The ASTIS database cites the following 7 publication(s) by Ed McCauley. Publications are listed from newest to oldest. Please tell us about publications that are not yet cited in ASTIS.
Arctic freshwater systems : trans-ecosystem integrators of climate and environmental change / Wrona, F.J. Prowse, T.D. McCauley, E. Peters, D. Flanagan, K. Gantner, K. di Cenzo, P.D. de Rham, L. Thompson, M. Mesquita, P. Hille, E. Moquin, P. Kokelj, S.
In: ArcticNet programme 2010 : annual scientific meeting, 14-17/12/2010, Ottawa, ON = ArcticNet programme 2010 : réunion scientifique annuelle, 14-17/12/2010, Ottawa, ON. - [Québec, Québec] : ArcticNet, 2010, p. 26-27
Abstract of a Topical Session presentation.
Indexed a PDF file from the Web.
One of the authors names, S. Kokelj was mis-spelled and appeared as S. Kokejl on the abstract.
ASTIS record 75307.
Projected changes/shifts in climatic regimes in the Arctic regions are expected to have far-reaching cascading impacts on the hydrology and ecology of northern/Arctic freshwater ecosystems. Freshwater systems are particularly sensitive to climate variability and change (CVC) because numerous hydro-ecological processes respond to even small changes in the climate and related cyrospheric regimes. Furthermore, hydrological and ecological processes may change either gradually or in an abrupt manner when environmental/ecosystem thresholds are exceeded. A significant amount of uncertainty still remains however, in predicting the direct and indirect physical, geochemical and ecological responses of arctic freshwater ecosystems to CVC. Under ArcticNet, we have been conducting a series of integrated hydrological and ecological studies assessing the impacts of landscape and freshwater-ice related cryospheric changes on the hydrology, geochemistry, and food web responses of upland Arctic lakes. Drawing upon examples from our and other relevant studies, I will discuss the importance of freshwater systems as trans-ecosystem integrators of climate and environmental change. In addition, I illustrate some of the major challenges involved in understanding and predicting impacts and responses at appropriate spatial and temporal scales and will provide some perspectives on future research directions. (Au)
F, E, J
Climate change; Environmental impacts; Food chain; Fresh-water ecology; Geochemistry; Hydrology; Lake ice; Lakes
Experimental warming increases CO2 saturation in a shallow prairie pond / Flanagan, K.M. McCauley, E.
(Aquatic ecology, v. 44, no. 4, Dec. 2010, p. 749-759, ill.)
ASTIS record 74596.
There is an urgent need to understand the effect of climate warming on the carbon dynamics of lakes and ponds in order to assess contributions to global carbon budgets. Currently, we are unable to predict how the exchange of carbon gases (i.e. CO2) across the air-water boundary and organic carbon storage in the sediments will be altered with realistic warming scenarios downscaled from climatic models. Given the prevalence of shallow systems and tight atmospheric coupling, we conducted a mesocosm experiment to test the impacts of warming on CO2 saturation in a shallow prairie pond. We outline and test three possible scenarios for the effect of warming on the CO2 saturation of ponds, resulting in either an increase, decrease or no net effect for CO2 saturation. We show that with approximately a two-degree (8C) increase in average water temperature, the pCO2 of the warmed mesocosms was nine times greater than the ambient temperature mesocosms by the end of the 5-week experiment. Changes in water colour (a measure of dissolved organic carbon) in warmed systems indicate that decomposition of organic matter in the sediments and water column was the main contributor to the increase in pCO2 in the warmed mesocosms. Our results show that with warming, the release of CO2 from shallow ponds to the atmosphere will increase and carbon storage in the sediments will decrease, altering the current functioning of shallow prairie ponds and influencing the contribution of ponds to the global carbon cycle. (Au)
J, E, F, H, I
Algae; Animal population; Bacteria; Biomass; Bottom sediments; Carbon cycling; Carbon dioxide; Chlorophyll; Climate change; Dissolved organic carbon; Effects monitoring; Fresh-water ecology; Lake-atmosphere interaction; Lakes; Mathematical models; Measurement; Phosphorus; Physical properties; Phytoplankton; Plant respiration; Primary production (Biology); Temperature; Testing; Water pH; Zooplankton
Climate change impacts on the CO2 dynamics of Arctic lakes / Flanagan, K. Thompson, M. Wrona, F. Prowse, T. McCauley, E. Peters, D.
In: ArcticNet programme 2009 : annual scientific meeting, 8-11/12/2009, Victoria, B.C. = ArcticNet programme 2009 : réunion scientifique annuelle, 8-11/12/2009, Victoria, B.C. - [Québec, Québec] : ArcticNet, 2009, p. 40-41
Abstract of a Topical Session presentation.
Indexed a PDF file from the Web.
ASTIS record 75306.
The complex and multifaceted perturbations caused by climate variability and change creates an impetus for research aimed at understanding the consequences for the ecology and hydrology of sensitive Arctic freshwater ecosystems. Climate change is anticipated to manifest in many ways for Arctic freshwater bodies including, changes to the physical structure of the ecosystem through the thawing of permafrost, altered inputs of nutrients and carbon to lakes, changes in length of growing season, and possibly changes in the species composition and food web structure. All of these alterations have the potential to affect the net balance of primary production and respiration in lakes, thereby altering the observed concentrations of ecologically important gases, such as, carbon dioxide (CO2). Changes to CO2 concentrations in Arctic lakes may have important consequences for the net carbon balance of Arctic ecosystems as a whole. In the terrestrial landscape, as Arctic permafrost thaws, carbon stored in the permafrost becomes bio-available for respiration, and carbon previously stored in the landscape for decades to millennia is released back into the atmosphere. There is a lack of knowledge about how the carbon flux rates of lakes, which are typically 'hot spots' in the landscape in terms of carbon turnover, are going to respond to permafrost degradation. Here we examine the open water dissolved CO2 concentrations of lakes experiencing large-scale permafrost degradation and slumping, and compare concentrations in these lakes to those in paired lakes unaffected by slumping. We find that the concentration of CO2 in the slumped lakes is significantly lower than the concentration of unaffected lakes. This result is surprising given the increased availability of carbon in the slumped lakes; however, it appears based on preliminary carbon isotope data that the carbon substrate in slumped lakes is in mineral carbonate form, rather than organic matter available for microbial degradation. In addition, matter available for microbial degradation. In addition, changes in the food web, macrophyte biomass and dissolved organic carbon presence may be altering the functioning of slumped lakes causing them to sequester more carbon dioxide. The impact of increased carbon sequestration of lakes affected by permafrost degradation may be counter-intuitive given the current observations in terrestrial systems and further investigation into the mechanisms controlling the shift in CO2 concentration are important for understanding carbon cycling on the Arctic landscape. These changes could dramatically alter the role of Arctic systems in terms of carbon storage and carbon sequestration, potentially having implications for carbon cycling at a global scale. (Au)
F, E, C, H, J
Biomass; Carbon cycling; Carbon dioxide; Carbonates; Climate change; Dissolved organic carbon; Environmental impacts; Food chain; Fresh-water ecology; Fresh-water flora; Growing season; Lakes; Mass wasting; Permafrost; Plant respiration; Primary production (Biology); Thawing
Hydro-ecological responses of Arctic tundra lakes to climate change and landscape perturbation : highlights and preliminary results / Wrona, F. Peters, D.L. Prowse, T.D. McCauley, E. Kokelj, S.V. Thompson, M.S. Mesquita, P.S. Dibike, Y.B. di Cenzo, P.D.
In: Arctic change 2008 : conference programme and abstracts, Québec (Qc), 9-12 December, 2008 = Arctic change 2008 : programme et résumés de la conference, Québec (Qc), 9-12 décembre 2008. - [Québec, Québec] : ArcticNet, 2008, p. 166
Abstract of a Topical Session presentation.
Indexed a PDF file from the Web.
ASTIS record 67041.
The Arctic Climate Impact Assessment (ACIA) concluded that the annual mean warming for the areas north of 60°N to be 3.7°C for the period 2070-2089. Arctic land areas are expected to display a warming that is more rapid than the global average in the cold season, a decrease in diurnal temperature range, a decrease in daily variability of surface air temperature in winter and an increase in daily variability in summer, and a decrease/degradation of the cryosphere (snow, permafrost and ice cover). Such significant changes/shifts in climatic regimes are expected to have far-reaching first- and second-order impacts on the hydrology and ecology of northern/Arctic freshwater ecosystems. Freshwater systems are particularly sensitive to climate variability and change (CVC) because numerous hydro-ecological processes respond to even small changes in the climate regime. Furthermore, hydrological and ecological processes may change either gradually or in an abrupt manner when environmental/ecosystem thresholds are exceeded. A significant amount of uncertainty still remains however, in predicting the direct and indirect physical, geochemical and ecological responses of arctic freshwater ecosystems to CVC. The lake-rich upland tundra landscape east of the Mackenzie River Delta, NT, contains aquatic ecosystems that are projected to be impacted by CVC and other environmental stressors (e.g., resource development) in the next few decades. Large-scale permafrost degradation (increased depth of seasonal active layer and/or landscape slumping) is predicted to increase with the effects of climate warming, along with enhanced addition of geochemical loadings (e.g., carbon, nitrogen, phosphorus) to the freshwater environment. In addition, changes in the timing and duration of lake-ice characteristics in conjunction with altered geochemical loadings are projected to dramatically affect under-ice and open-water oxygen regimes, 1° and 2° production relationships, and carbon flux. To investigate and reduce the uncertainties pertaining to the sensitivities and responses of Arctic tundra lakes to CVC and other environmental stressors, the ArcticNET project "Hydro-ecological Responses of Arctic Tundra Lakes to Climate Change and Landscape Perturbation" was designed to: (i) improve our regional understanding of the sensitivities/responses of the Mackenzie upland tundra lakes to CVC through integrated landscape-lake process and modelling studies; and (ii) develop and validate an integrated landscape-lake ice, hydro-ecological model applicable to cold regions/Arctic systems. This presentation provides an overview of the project design along with highlights and preliminary results. (Au)
F, J, C, G, E
Active layer; Atmospheric temperature; Biological productivity; Carbon; Climate change; Effects of climate on ice; Effects of climate on permafrost; Environmental impacts; Fresh-water ecology; Lake ice; Mathematical models; Nitrogen; Oxygen; Permafrost; Phosphorus; Temporal variations; Thawing; Thickness; Tundra ponds
Mackenzie Delta, N.W.T.
Carbon dynamics in lakes of the boreal forest under a changing climate / Benoy, G. Cash, K. McCauley, E. Wrona, F.
(Environmental reviews, v. 15, Mar. 2007, p. 175-189, ill., map)
ASTIS record 75303.
Water-covered lands comprise approximately 30% of the total area of the world's boreal forest biome. Most of these lands are peatlands (i.e., bogs and fens), which store over half of the total carbon in the biome. Because climate warming threatens to alter the carbon stocks of peatlands, much attention has been devoted to understanding the climatic and hydrologic conditions that affect peatland biogeochemistry. However, there are other aquatic systems that are widespread in the boreal forest that also process and store carbon, including lakes and ponds. Although non-peatland aquatic systems cover a much smaller portion of the boreal landscape, they still contain approximately 15% of the total carbon pool for the biome, much of it stored as either profundal or littoral sediments. Further, the carbon dynamics of boreal lakes are dynamically coupled to watershed processes. Excepting major disturbances to boreal catchments, such as forest fires and forest harvest, surface waters are the only locations of net loss of carbon to the atmosphere. Our objectives are to review what is known about factors that affect lake ecosystem carbon dynamics in the boreal forest and to identify areas of study that we deem to be profitable for forecasting the impacts of climate change on carbon pools and flux rates. We primarily focus on the boreal forest of North America, but recognize that our findings may also be relevant for boreal areas of Fennoscandia and Russia. The following research priorities are identified: (i) estimation of carbon pools in profundal and littoral sediments across the boreal forest, (ii) warming experiments that include quantification of ecosystem carbon dynamics in addition to measuring changes to aquatic food web structure, (iii) whole system experiments to understand the hydrologic and biogeochemical conditions by which allochthonous carbon is integrated into aquatic food webs, especially in the context of increased nutrient concentrations associated with a warmer, and possibly drier, climate, as forecast for the southern boreal forest, (iv) watershed-scale assessment of carbon budgets for lakes that straddle transitional zones between the boreal forest and prairie-parkland, temperate forest or tundra, to detect evidence of ecosystem migration, and (v) integration of lacustrine carbon pools and flux rates into carbon budgets at scales that range from local watersheds to the boreal forest biome. (Au)
F, B, E, J, H, C, I
Algae; Atmospheric temperature; Biomass; Bottom sediments; Carbon; Carbon cycling; Carbon dioxide; Climate change; Effects of temperature on plants; Environmental impacts; Evaporation; Food chain; Fresh-water ecology; Groundwater; Hydrology; Lake-atmosphere interaction; Lakes; Methane; Peat; Plant distribution; Plant respiration; Plants (Biology); Precipitation (Meteorology); Primary production (Biology); Rivers; Runoff; Soils; Taiga ecology; Temperature; Trophic levels; Watersheds; Wetlands; Zooplankton
Canada; Canadian Arctic
Climate change : the potential for latitudinal effects on algal biomass in aquatic ecosystems / Flanagan, K.M. McCauley, E. Wrona, F. Prowse, T.
(Canadian journal of fisheries and aquatic sciences, v. 60, no. 6, June 2003, p. 635-639, ill.)
ASTIS record 75300.
Arctic aquatic systems are considered to be highly susceptible to climate change. Both increases in temperature and nutrient input would be anticipated to alter primary production within these lakes. Consequently, understanding the current relationship between nutrients and productivity is crucial for predicting the effects of climate change. In this paper, we synthesize published data on algal biomass, total phosphorus, total nitrogen, maximum depth, altitude, longitude, and latitude to determine whether average algal biomass differs for temperate and arctic lakes. A total of 57 sources were used, resulting in data for 433 lake-years, ranging in latitudes from 41 to 79°N. Average algal biomass observed during the ice-free season increased significantly with phosphorous levels, but the latitude of the system had a significant negative impact on algal biomass. We briefly outline two major hypotheses, based on existing empirical evidence, for the lower algal yield found in higher latitude systems. The first hypothesis discusses bottom-up control and the influence of abiotic factors on algal biomass. The second hypothesis relates to food chain composition and top-down influences. The latitudinal effect on algal yield suggests that arctic lakes could dramatically increase in productivity if these systems experience increases in temperature and nutrient concentrations as predicted by climate change models. (Au)
H, I, F, J, E
Algae; Biomass; Chlorophyll; Climate change; Environmental impacts; Food chain; Fresh-water ecology; Growing season; Lake ice; Lakes; Nitrogen; Phosphorus; Phytoplankton; Plant distribution; Plant growth; Plant nutrition; Primary production (Biology); Seasonal variations; Solar radiation; Spatial distribution; Temperature; Thermal regimes; Trophic levels; Zooplankton
G081, G08, G06
Canadian Arctic; North American Arctic; North American Subarctic
Contaminant sources, distribution and fate in the Athabasca, Peace and Slave River basins, Canada / Wrona, F.J. Carey, J. Brownlee, B. McCauley, E.
(Journal of aquatic ecosystem stress and recovery, v. 8, no. 1, Nov. 2000, p. 39-51, ill., maps)
ASTIS record 75302.
Northern river ecosystems worldwide are under increasing environmental stress from degrading developments that influence water quality and associated ecological integrity. In particular, contaminant-related threats to these systems are rising from enhanced industrial and municipal effluent discharges along with elevated non-point source inputs related to land-use activities such as forestry, agriculture, mining and long-range atmospheric transport. In this regard, the contaminants program of the Northern River Basins Study (NRBS) in western Canada identified key contaminant sources to the Athabasca, Slave and Peace river basins (particularly related to pulp-mill developments) and assessed their environmental fate and distribution in water and sediments. The study also developed and employed new analytical approaches and generated improved models to predict contaminant transport and fate in the aquatic environment and related food webs. Consequently the study focused on those contaminant families identified in characterization studies as arising from key point- and non-point sources within the basins or as being of greatest toxicological significance. These included resin acids, polychlorinated dioxins and furans, polychlorinated biphenyls, chlorinated phenolics, polyaromatic hydrocarbons and selected heavy metals such as mercury. Low or non-detectable concentrations of a number of contaminant groups were found in the ambient water phase including chlorinated phenolics, some chlorinated dioxins and furans and some resin acids. For both suspended and depositional sediments, significant declines were observed over the study period for the major chlorinated contaminant groups tested, correlating directly with the implementation of improved effluent treatment in many of the pulp mills located in the basins. In general, the environmental levels of chlorinated organic and metal contaminants in water or sediments were low and within Canadian health or environmental guidelines. It is hoped that the approaches used and lessons learned from the NRBS will be of use to others assessing contaminant and multiple stressor issues in other large river ecosystems. (Au)
F, B, N, Q, J, E
Agronomy; Air pollution; Atmospheric chemistry; Bottom sediments; Chlorophenols; Cores; Databases; Dioxins; Environmental impacts; Food chain; Forestry; Fresh-water ecology; Furans; Heavy metals; Lake-atmosphere interaction; Lakes; Mathematical models; Mercury; Oil refineries; Oil sands; Organochlorines; PAHs; PCBs; Pollution; Pulp and paper industry; Risk assessment; Rivers; Runoff; Sewage disposal; Spatial distribution; Specifications; Suspended solids; Temporal variations; Toxicity; Water pollution; Water quality; Water treatment
Athabasca River region, Alberta; Peace River region, Alberta/British Columbia; Slave River region, Alberta/N.W.T.
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