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Found 10 records similar to Historic mercury and heavy metal deposition in Kejimkujik National Park, Nova Scotia reconstructed from lake sediment cores
The Experimental Lakes Area (ELA), in Ontario, Canada, is a sensitive region for heavy metal contamination, such as mercury, in part due to long-range atmospheric deposition from global and regional industrial regions. The region is remote from industrial centres, but is downwind of major pollution sources in North America and Canada, and historically had numerous gold mining sites. Supplemental Information
The Climate Change and Air Pollution (CCAP) program was established in 2016 to identify the severity and extent of adverse impacts of current and future air emissions on aquatic ecosystems to support regulatory actions and policy development. The program includes a number of components, including identifying, monitoring and defining air quality and greenhouse gas (GHG) concerns; improving our understanding of the short- and long-term effects of atmospheric pollutants on the environment; developing a plan to combat climate change; and monitoring and reducing both domestic and transboundary emissions of GHGs.
The Flin Flon copper–zinc smelter is a site of concern as it has been the largest single source of atmospheric mercury emissions in Canada until operations ceased on July 1, 2010. The smelting and mining activities resulted in mercury contamination to the local environment. Elevated levels of mercury and other trace metals were found in soil humus, peat, plants, fish and sediment cores. The Flin Flon smelter of the Hudson Bay Mining and Smelting Company is located near the Manitoba–Saskatchewan border, 600 km Northwest of Winnipeg and over 400 km away from other major industrial complexes.This study examined nine lakes (Nekik, Douglas, Loucks, Phantom, McClurg, Cleaver, Naosep, Hamel, and Meridian) each lake was located at varying differences within 75 km of the smelter stack these lakes were selected for sediment coring analysis and heavy metal deposition trends.
Lake sediment cores were collected from several locations in Canada as part of the historic mercury and heavy metal deposition trend, analysis, and research component of the Clean Air Regulatory Agenda/Climate Change and Air Pollutant (CARA/CCAP) and Oil Sands Monitoring (OSM) programs. The reason sediment core analysis is used for research purposes is the bottom of a lake can act as a record of the contaminants and all other materials which have fallen into the lake over time. The lake water acts as both a sorting device and as a preservative since the deposits fall in chronological order and if not subject to dredging are not normally otherwise disturbed by humans. In areas where depositional histories are complex, including changing contributions from local, regional and global sources, multiple dated lake sediment cores are useful tools for examining response of not only aquatic ecosystems, but their surrounding landscapes through time to changing emission/deposition scenarios.
Recent and historical deposition of mercury (Hg) are examined over a broad geographic area from southwestern Northwest Territories to Labrador and from the U.S. Northeast to northern Ellesmere Island using dated sediment cores from 50 lakes (18 in midlatitudes (41-50 degrees North), 14 subarctic (51-64 degrees North) and 18 in the Arctic (65-83 degrees North)). Objectives were to quantify latitudinal and longitudinal trends of anthropogenic mercury deposition in eastern and northern North America, to investigate variations in mercury deposition, to examine relationships with lake area, catchment/lake area ratio and sedimentation rates, and to compare results with model predictions. Distinct increases of mercury over time were observed in 76% of Arctic, 86% of subarctic and 100% of midlatitude cores. Subsurface maxima in mercury depositional fluxes were observed in only 28% of midlatitude lakes and 18% of arctic lakes, indicating little recent reduction of inputs.
Measurements of gaseous elemental mercury (GEM), gaseous oxidized mercury (GOM) and particulate bound mercury on PM2.5 (referred to as PBM2.5) were collected by Environment and Climate Change Canada from August to September 2013 at the Wood Buffalo Environmental Association (WBEA) Air Monitoring Station (AMS) 13 – Fort McKay South, and at WBEA AMS 4 – Buffalo Viewpoint. Monitoring resumed at WBEA AMS 13 in September 2014 with two speciated mercury instruments and is ongoing. One speciated mercury instrument monitors GEM, GOM, and PBM2.5; the second speciated mercury instrument monitors GEM, GOM, and mercury on PM10 (referred to as PBM10). These data are the first atmospheric speciated mercury measurements to be reported in the oil sands region.
Ambient concentrations of speciated mercury (Hg) have been measured at many locations across Canada. Mercury in the atmosphere is measured in three operationally-defined forms - gaseous elemental mercury (GEM), reactive gaseous mercury (RGM), and particulate-bound mercury (PBM). Under most conditions, GEM (or Hg0) is the predominant species in the air (~95-99%), while RGM and PBM concentrations are typically two orders of magnitude lower, i.e., <5% of the total atmospheric mercury concentration (Schroeder and Munthe, 1998). Reactive gaseous mercury is thought to consist of compounds such as HgCl2, HgBr2, Hg(OH)2 (Lin and Pehkonen, 1999), although the exact composition is unknown.
The atmospheric monitoring subcomponent of the Northern Contaminants Program (NCP) studies long-range transport of anthropogenic organic pollutants in air (AOPA), mercury, and chemicals of emerging arctic concern from around the globe. This subcomponent includes three NCP Core Monitoring Projects, namely “Northern Contaminants Air Monitoring: Organic Pollutant Measurements”, “Mercury Measurements at Alert and Little Fox Lake”, and “Passive Air Sampling Network for Organic Pollutants and Mercury”. Long-term air measurements of contaminants are collected continuously throughout the year. In addition, there are several passive air sampling stations across the Arctic.
The Canadian Air and Precipitation Monitoring Network (CAPMoN), operated by Environment and Climate Change Canada (ECCC), is designed to study the regional patterns and trends of atmospheric pollutants such as acid rain, smog, particulate matter and mercury, in both air and precipitation. The network began operating in 1983. CAPMoN updated and replaced two older networks known as the Canadian Network for Sampling Precipitation (CANSAP) and the Air and Precipitation Network (APN). The integration of APN as part of CAPMoN extended the data record as far back as 1978.
Measurements of gaseous elemental mercury (GEM), gaseous oxidized mercury (GOM) and particulate bound mercury on PM2.5 (referred to as PBM) are currently collected by Environment and Climate Change Canada at a Wood Buffalo Environmental Association (WBEA) Air Monitoring Station (AMS). Preliminary, three-hour averaged speciated mercury data from the oil sands region are available for WBEA AMS 13 – Fort McKay South, located near Fort McKay, Alberta. There are no Environment and Climate Change Canada or Canadian Council of Ministers of the Environment (CCME) air quality guidelines, nor Alberta Ambient Air Quality Objectives for speciated Hg measurements. The monitoring follows the established Canadian Air and Precipitation Monitoring Network (CAPMoN) standard operating procedures.
The Common loon is a highly visible water bird inhabiting many of the lakes within Kejimkujik and the greater park ecosystem. It is a top predator in freshwater ecosystems in the area and is sensitive to a variety of stressors, including mercury bio-accumulation, acidification, water level fluctuation and human disturbance. The monitoring program tracks loon population status, by recording the number of adult pairs and number of chicks on focal lakes at Kejimkujik. Monitoring occurs twice annually in June and August using field observations from volunteers and park staff.