Observations on various types of wetlands, terrestrial environments, and vascular plants for 102 sites visited in 2012 and located on Lake Saint-Pierre are included in this dataset. Since the 1970s, Environment and Climate change Canada (ECCC) has been monitoring changes in wetlands under the State of the St. Lawrence River Monitoring program of the St. Lawrence Action Plan.

Black carbon is a short-lived, small aerosol (or airborne) particle linked to both climate warming and adverse health effects. It is emitted from incomplete combustion of carbon-based fuels (i.e., fossil fuels, biofuels, wood) in the form of very fine particulate matter. Black carbon is not emitted on its own, but as a component of particulate matter less than or equal to 2.5 micrometres in diameter (PM2.5). As a member of the Arctic Council, Canada has committed to producing an annual inventory of black carbon emissions. This data will serve to inform Canadians about black carbon emissions and provide valuable information for the development of air quality management strategies. The data used to compile the report originate from sections of the Air Pollutant Emission Inventory (APEI) specifically fine particulate matter (PM2.5) emissions from combustion-related sources.

Observations on various types of wetlands, terrestrial environments, and vascular plants for 55 sites visited in 2012 and located in in the Boucherville Islands are included in this dataset. Since the 1970s, Environment and Climate Change Canada (ECCC) has been monitoring changes in wetlands under the State of the St. Lawrence River Monitoring program of the St. Lawrence Action Plan.

The transition from tadpole to frog (metamorphosis) and gender differentiation are tightly controlled by the endocrine systems and hormones, where exposure to even low concentrations of certain environmental contaminants can change normal hormone processes that have severe effects on biological development and thus the production of healthy, reproductively capable individuals. We will assess the effects of potential endocrine disrupting CMP3 priority substances, where tadpoles are exposed to environmentally relevant concentrations in water or sediment and assessed for effects on time to metamorphosis, growth, gender, expression of genes involved in development and sexual differentiation and histology of thyroid and gonadal tissue.

The Duck Lake (Saskatchewan) Geolysimeter precipitation intercomparison data are from a co-located precipitation gauge and deep groundwater observation well. The data published here are event based intercomparisons, collected between 2010 and 2016, binned into rain and snow events. Snowfall data observed by the precipitation gauge have been adjusted for wind bias using the SPICE (Solid Precipitation InterComparison Experiment) transfer functions (Kochendorfer et al., 2017a) and included for intercomparison. The data is described by Smith et al. (2017b) in https://www.hydrol-earth-syst-sci-discuss.net/hess-2017-174/ . Both data sets (gauge precipitation and well water level observations) have been quality controlled and processed.

Drainage of surface water on Arctic landscapes that are underlain by continuous permafrost is limited, thus such areas are characterized by an abundance of diverse aquatic habitats that support a variety of fish and wildlife. On the Arctic Coastal Plain, shallow tundra ponds (hereafter wetlands), in particular, provide important invertebrate forage for breeding shorebirds, which rely on an abundance of local arthropods for successful reproduction. Unlike wetlands in more southern locations, however, there is a lack of basic ecological information about Arctic wetland invertebrate fauna, and factors that regulate their abundance are poorly understood. This type of knowledge will be necessary to accurately predict how wetland-dependent wildlife will respond to changing environmental conditions across the Arctic.

Mercury has been increasing in some marine birds in the Canadian Arctic over the past several decades. To evaluate the potential reproductive impact of mercury exposure, eggs of two species of arctic-breeding seabirds, the thick-billed murre and arctic tern, were dosed with graded concentrations of methylmercury and artificially incubated in the laboratory to determine species differences in sensitivity. Based on the dose-response curves, the median lethal concentrations (LC50) for thick-billed murre and arctic tern embryos were calculated. Compared with published LC50 values for other avian species, the murres and terns had a medium sensitivity to methylmercury exposure.

Sediment methylation and demethylation rates were measured by short-term incubations of stable isotopes of inorganic and methylmercury in sediment cores. Methylmercury photodemethylation rates were performed, during which water samples were incubated in the field under different treatments. Some bottles were spiked with methylmercury or complexing agents and scavengers. Labile concentrations of methylmercury were measured in water and sediment using DGT (Diffusive Gradient in Thin Film) samplers. Characterization of the microbial community in sediment and quantification of targeted microbes potentially involved in MeHg cycling were performed using qRT-PCR approaches, cloning and library analyses combined with gel electrophoresis techniques. Methylmercury bioaccumulation at the base of the food web was examined by collecting filamentous benthic algae and chironomid larvae from nearshore and offshore areas in the study lakes.

There are 341 listed contaminated sites in the National Capital Region under federal jurisdiction. Many of these sites are still active, and at various stages of remedial action. Continued monitoring of contaminants is of interest to the National Capital Commission who manages the greatest proportion of these sites. Semi-aquatic furbearers are considered sentinel species of ecosystem health and could provide valuable data for post-mitigation monitoring. Through an already established collaboration with conservation officers of the NCC, carcasses will be submitted for contaminant analyses at the NWRC and wildlife health assessments at the CWHC, and the University of Alberta.