Filters: Tags: Methylmercury (X)
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Macroinvertebrate samples were collected from streams tributary to Honnedaga Lake and from the Middle Branch of the Black River during 2012-2016 and analyzed for methylmercury concentrations and for stable isotope ratios of nitrogen and carbon. Macroinvertebrates were identified in the field, and the level of taxonomic resolution varied from order to species; most taxa were identified to the family level. Specimens were field-processed into composite samples, field-frozen, and submitted to the mercury laboratory for freeze-drying and analysis. Subsamples were then submitted to the stable isotope laboratory for analysis of nitrogen and carbon isotope ratios. This database contains the resulting data and associated...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Ambient Monitoring,
Aquatic Biology,
Aquatic Community Health,
Ecosystem Health,
Environmental Health,
The small watershed approach is well-suited but underutilized in mercury research. We applied the small watershed approach to investigate total mercury (THg) and methylmercury (MeHg) dynamics in streamwater at the five diverse forested headwater catchments of the US Geological Survey Water, Energy, and Biogeochemical Budgets (WEBB) program. At all sites, baseflow THg was generally less than 1 ng L−1 and MeHg was less than 0.2 ng L−1. THg and MeHg concentrations increased with streamflow, so export was primarily episodic. At three sites, THg and MeHg concentration and export were dominated by the particulate fraction in association with POC at high flows, with maximum THg (MeHg) concentrations of 94 (2.56) ng L−1...
Categories: Publication;
Types: Citation;
Tags: Episodic transport,
Methylmercury,
Total mercury,
Watershed
The diversion of freshwater from the Mississippi River is intended to mitigate saltwater intrusion from the Gulf of Mexico and to lessen the concomitant loss of wetland areas. Though effective, freshwater diversion can affect wildlife and habitat; therefore, prediversion and postdiversion data collections are necessary to identify effects. The Davis Pond freshwater diversion area is located between the Mississippi River and Bayou Lafourche and extends to Barataria Bay Basin, Louisiana. Results and interpretations from the prediversion biomonitoring done in 2001- which included data on fish, eagles, and bivalves - are presented in the U.S. Geological Survey (USGS) Scientific Investigations Report 2008-5067, "Davis...
This dataset consists of concentration and isotopic data for a method designed to isolate and analyze methylmercury. Several matrices (lab-based, and natural) were tested to ensure that the method was capable of recovering methylmercury amendments. Additionally, natural matrices (plankton and sediment) with ambient methylmercury were also analyzed to ensure that the method could be successfully applied to natural matrices. Separation tests for sediment, water, and biotic matrices showed acceptable recoveries (98 ± 5%, n = 54) and reproducible δ202Hg isotope results (2SD < 0.15 ‰) down to 5 ng of MeHg. This dataset is part of a complimentary paper published in Analytical and Bioanalytical Chemistry (https://doi.org/10.1007/s00216-019-02277-0)...
Categories: Data;
Tags: Environmental Health,
Fox River, WI,
Geochemistry,
Lake Mendota, WI,
Lake Michigan,
The geospatial data presented here as ArcGIS layers denote landcover/landuse classifications to support field sampling efforts that occurred within the Cache Creek Settling Basin (CCSB) from 2010-2017. Manual photointerpretation of a National Agriculture Imagery Program (NAIP) dataset collected in 2012 was used to characterize landcover/landuse categories (hereafter habitat classes). Initially 9 categories were assigned based on vegetation structure (Vegtype1). These were then parsed into two levels of habitat classes that were chosen for their representativeness and use for statistical analyses of field sampling. At the coarsest level (Landcover 1), five habitat classes were assigned: Agriculture, Riparian, Floodplain,...
The Cache Creek Settling Basin (CCSB) is a 13.3 km2 leveed basin located at the terminal drainage of the Cache Creek watershed, immediately NE of the town of Woodland (Yolo County), California and approximately 18 km NW of Sacramento, California. The basin was constructed by the U.S. Army Corps of Engineers (completed in 1937 and modified in 1993) for the purpose of trapping suspended sediment transported from the upper Cache Creek watershed during high-flow events, thus preventing sediment from entering the Yolo Bypass, a larger downstream floodwater conveyance and agricultural zone. In addition to trapping suspended sediment, the CCSB also traps sediment-associated mercury (Hg), which is particularly elevated...
It is widely recognized that wetlands, especially those rich in organic matter and receiving appreciable atmospheric mercury (Hg) inputs, are important sites of methylmercury (MeHg) production. Extensive wetlands in the southeastern United States have many ecosystem attributes ideal for promoting high MeHg production rates; however, relatively few mercury cycling studies have been conducted in these environments. We conducted a landscape scale study examining Hg cycling in coastal Louisiana (USA) including four field trips conducted between August 2003 and May 2005. Sites were chosen to represent different ecosystem types, including: a large shallow eutrophic estuarine lake (Lake Pontchartrain), three rivers draining...
Categories: Publication;
Types: Citation;
Tags: Dissolved organic carbon,
Louisiana,
Mercury,
Methylmercury,
Sulphate,
This data release provides data for filter-passing total mercury, filter-passing methylmercury, particulate total mercury, particulate methylmercury, and dissolved organic carbon concentrations calculated for USGS station 254543080405401: Tamiami Canal at S-12D Near Miami, FL. Five site-specific regression models were developed using continuously measured temperature, turbidity, specific conductance and or fluorescence of chromophoric dissolved organic matter and concomitant discretely collected dissolved organic carbon samples to calculate continuous concentrations of mercury and carbon.
Categories: Data;
Tags: Everglades,
S-12D,
Tamiami Trail,
USGS Science Data Catalog (SDC),
Water Quality,
Samples were collected at or near baseflow conditions. Water pH and specific conductance were measured in the field, with specific conductance also measured in the laboratory and calculated based on the ionic strength of samples based on laboratory analyses. Water samples were collected for laboratory analyses using a peristaltic pump with silicon tubing. Samples were filtered through a reusable plexiglass filter holder with nylon screws using 0.45µm polyethersulfone membranes that were rinsed with approximately 20mL of sample water prior to collection. Splits were also collected unfiltered to determine trace metal concentrations associated with suspended sediments. The filtration apparatus was rinsed with deionized...
Categories: Data;
Types: Citation;
Tags: East Fork South Fork Salmon River,
Idaho,
Stibnite,
USGS Science Data Catalog (SDC),
Valley County,
The movement of mercury (Hg) from the atmosphere to the biosphere occurs by both wet and dry deposition to solid surfaces, water, and vegetation. Most of the annual dry atmospheric Hg deposition in deciduous forests is believed to originate from litterfall which consists mainly of dead leaves that fall to the earth’s surface, primarily during the autumn and winter seasons. Atmospheric Hg reaches an annual maximum concentration in leaves at the time of leaf fall. Analysis of litterfall samples helps to quantify total annual atmospheric Hg deposition to forests when combined with precipitation Hg data. This data set is derived from litterfall samples collected during 2017-18 and 2018-19 at 27 selected National Atmospheric...
Categories: Data;
Tags: Ambient Monitoring,
Ecology,
Ecosystem Health,
Ecosystem Health,
Environmental Health,
Mercury (Hg) was measured in stream water and precipitation in the Loch Vale watershed in Rocky Mountain National Park, Colorado, during 2001–2002 to investigate processes controlling Hg transport in high-elevation ecosystems. Total Hg concentrations in precipitation ranged from 2.6 to 36.2 ng/L and showed a strong seasonal pattern with concentrations that were 3 to 4 times higher during summer months. Annual bulk deposition of Hg was 8.3 to 12.4 μ g/m2 and was similar to deposition rates in the Midwestern and Northeastern U.S. Total Hg concentrations in streams ranged from 0.8 to 13.5 ng/L and were highest in mid-May on the rising limb of the snowmelt hydrograph. Stream-water Hg was positively correlated with dissolved...
Categories: Publication;
Types: Citation;
Tags: atmospheric deposition,
dissolved organic carbon,
methylmercury,
snowmelt,
watershed budge
This dataset includes mercury and other constituent concentration and physical properties data for surface sediment, pore water and surface water collected as part of the South San Francisco Bay Salt Pond Restoration Phase 1 (2010 to 2018) studies. The overarching focus of these studies was to monitor mercury (Hg) biogeochemistry in both sediment and water in response to management actions associated with the conversion of former salt producing ponds to contemporary wetland habitat. The two primary management actions included the breaching of Pond A6 during December 2010, and the construction and operation of an adjustable tidal control structure (TCS) associated with the Pond A5/A7/A8 Complex beginning in June...
Categories: Data;
Tags: Alviso Slough,
Alviso, CA,
Environmental Health,
Geochemistry,
Mountain View, CA,
This dataset includes shallow surface sediment (top 0–2 cm interval) constituent concentration data (primarily) and microbial methylmercury production potential rate data (limited) collected from the Cache Creek Settling Basin (CCSB), Yolo County, California, between April 2010 and July 2017. The dataset includes up to 706 observations (including field replicates) per sediment parameter, reflecting 93 unique sampling locations, with each location having been sampled from 1 to 28 times (excluding field replicates) over this 8-year period. There were four spatially intensive field campaigns conducted (February–March 2013, May 2013, October–November 2014, and January–March 2015), during which at least 90 sites were...
Mercury (Hg) was measured in stream water and precipitation in the Loch Vale watershed in Rocky Mountain National Park, Colorado, during 2001–2002 to investigate processes controlling Hg transport in high-elevation ecosystems. Total Hg concentrations in precipitation ranged from 2.6 to 36.2 ng/L and showed a strong seasonal pattern with concentrations that were 3 to 4 times higher during summer months. Annual bulk deposition of Hg was 8.3 to 12.4 μ g/m2 and was similar to deposition rates in the Midwestern and Northeastern U.S. Total Hg concentrations in streams ranged from 0.8 to 13.5 ng/L and were highest in mid-May on the rising limb of the snowmelt hydrograph. Stream-water Hg was positively correlated...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Water, Air, & Soil Pollution,
atmospheric deposition,
dissolved organic carbon,
methylmercury,
snowmelt,
Survival and size of mayflies at each life stage, as well as MeHg concentrations in diatoms and mayflies exposed to low and high MeHg concentrations and a range of selenomethione (SeMet) concentrations.
The geospatial data presented here as ArcGIS layers denote landcover/landuse classifications to support field sampling efforts that occurred within the Cache Creek Settling Basin (CCSB) from 2010-2019. Manual photointerpretation of a National Agriculture Imagery Program (NAIP) dataset collected in 2012 was used to characterize landcover/landuse categories (hereafter habitat classes). Initially 9 categories were assigned based on vegetation structure (Vegtype1). These were then parsed into two levels of habitat classes that were chosen for their representativeness and use for statistical analyses of field sampling. At the coarsest level (Landcover 1), five habitat classes were assigned: Agriculture, Riparian,...
This dataset includes bird species, invertebrate order and family, sample identification codes, capture date, latitude, longitude, habitat, site name, bird age, total mercury concentrations in bird blood, and methylmercury concentrations in whole body aquatic invertebrates.
Categories: Data;
Tags: Aquatic Biology,
Black Butte Mine,
Cottage Grove Lake,
Ecology,
Environmental Health,
Coastal communities are uniquely vulnerable to sea-level rise (SLR) and severe storms such as hurricanes. These events enhance the dispersion and concentration of natural and anthropogenic chemicals and pathogenic microorganisms that could adversely affect the health and resilience of coastal communities and ecosystems in coming years. The U.S. Geological Survey has developed the Sediment-Bound Contaminant Resiliency and Response (SCoRR) strategy to define baseline and post-event sediment-bound environmental health (EH) stressors. These data document the major element chemistry, major and trace chemical composition, total sulfur content, inorganic and organic carbon for soil and sediment samples from selected stations...
This dataset describes biomass and methylmercury concentrations in zooplankton, other invertebrates, fish, and coarse and fine detritus samples collected at the outflow locations of Brownlee and Oxbow Reservoirs in the Snake River Hells Canyon Complex. Based on the sampling locations, the sampled materials were presumed to have flowed through the dam turbines or over the spillway, thereby representing biological export from the reservoirs. Samples were collected biweekly at each location over a sixteen-month period, June 2018 – September 2019. Sampling and analysis methods are described in the Processing Steps section of the metadata.
This dataset includes laboratory analyses of surface water samples and sediment trap material collected from (1) locations upstream, downstream, and within the Hells Canyon Complex (Idaho, Oregon) of the Snake River, (2) tributaries of the Snake River, and (3) two reservoirs near Boise, Idaho, from 2014 to 2021. The study area spans approximately 232 river miles of the Snake River and includes: two sites on the main stem of the Snake River upstream of the Hells Canyon Complex (Snake River mile 447.6 and 345.6), six sites within Brownlee Reservoir (Snake River mile 318, 314, 310, 305, 300, and 286), one site within Oxbow Reservoir (Snake River mile 273), two sites within Hells Canyon Reservoir (Snake River mile 252...
Categories: Data,
Data Release - Under Revision;
Tags: Brownlee Dam,
Hells Canyon,
Idaho,
Oregon,
Oxbow Dam,
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