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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...
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...
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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...
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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)...
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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,...
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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...
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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.
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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...
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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...
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...
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This dataset includes field hydrologic measurements and laboratory analyses of surface and pore waters, sediments, benthic plants/biofilms, and biota along the Middle Snake River upgradient of the Hells Canyon Complex. The study region for this work focuses on a section of the Snake River heavily utilized for agriculture, with complex systems of irrigation diversion and return drainage, spanning 164 km above the Hells Canyon Complex (Idaho, Oregon). The goal of this study was to identify potential loading sources of methylmercury from the upgradient Snake River into the reservoir complex, with a focus on the tributaries, irrigation return drains, and riparian zones adjacent to agricultural lands along the river....
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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...
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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...
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 Î&frac14; 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...
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This USGS data release evaluates the impact of historical mining sites on water quality using samples collected in late July 2021 from Big Creek tributaries Coin Creek, Smith Creek, and Monumental Creek in Valley County, Idaho. These data were collected to support a fisheries mining impact assessment in the Middle Fork Salmon River. Specific conductance, pH, and stream temperature were measured in the field. Analyses include major cations and anions, alkalinity, trace metals, total mercury, and methylmercury.
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.
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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,...
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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.
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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.


map background search result map search result map Methylmercury Concentrations in Largemouth Bass from the Davis Pond Freshwater Postdiversion Sampling (2007-2009) Water and Sediment Geochemistry Data from the Vicinity of Yellow Pine, Idaho, 2014-2015 Shallow Sediment Geochemical Data for the Cache Creek Settling Basin, Yolo County, California, 2010–17 Habitat Maps for the Cache Creek Settling Basin, Yolo County, California Mercury speciation and other constituent data for surface sediment and water associated with the South San Francisco Bay Salt Pond Restoration, 2010-18 Total Mercury and Methylmercury in Riparian Songbirds and Aquatic Invertebrates from the Willamette Valley, Oregon, 2013-2014 Isolation of Methylmercury Using Distillation and Anion-Exchange Chromatography for Isotopic Analyses in Natural Matrices Data Release Methylmercury and associated data in macroinvertebrates from tributaries of Honnedaga Lake and from the Middle Branch Black River in New York. Calculated mercury and carbon concentrations, USGS station 254543080405401: Tamiami Canal at S-12D Near Miami, Florida, 2013-2017 Mercury and Methylmercury Concentrations in Litterfall Samples Collected at Selected National Atmospheric Deposition Program Sites during 2017 to 2019 Survival, growth, behavior and mercury concentrations of mayflies exposed to elevated dietary methylmercury and aqueous selenium Shallow Sediment Geochemistry in a Mercury-Contaminated Multi-Habitat Floodplain: Cache Creek Settling Basin, Yolo County, California (version 2.0, August 2021) Habitat Maps for the Cache Creek Settling Basin, Yolo County, California Biomass and methylmercury concentrations in biweekly biological samples from Brownlee and Oxbow Reservoir outflows, Snake River Hells Canyon Complex (Idaho-Oregon), 2018-2019 Water chemistry data from the Big Creek and Monumental Creek tributaries of the Lower Middle Fork Salmon River, Idaho, 2021 Hydrological, Chemical, and Biological Characterization of the Snake River and Associated Tributaries and Irrigation Drains from River Mile 448 to 346, 2022 Calculated mercury and carbon concentrations, USGS station 254543080405401: Tamiami Canal at S-12D Near Miami, Florida, 2013-2017 Survival, growth, behavior and mercury concentrations of mayflies exposed to elevated dietary methylmercury and aqueous selenium Habitat Maps for the Cache Creek Settling Basin, Yolo County, California Shallow Sediment Geochemistry in a Mercury-Contaminated Multi-Habitat Floodplain: Cache Creek Settling Basin, Yolo County, California (version 2.0, August 2021) Habitat Maps for the Cache Creek Settling Basin, Yolo County, California Shallow Sediment Geochemical Data for the Cache Creek Settling Basin, Yolo County, California, 2010–17 Mercury speciation and other constituent data for surface sediment and water associated with the South San Francisco Bay Salt Pond Restoration, 2010-18 Biomass and methylmercury concentrations in biweekly biological samples from Brownlee and Oxbow Reservoir outflows, Snake River Hells Canyon Complex (Idaho-Oregon), 2018-2019 Water chemistry data from the Big Creek and Monumental Creek tributaries of the Lower Middle Fork Salmon River, Idaho, 2021 Water and Sediment Geochemistry Data from the Vicinity of Yellow Pine, Idaho, 2014-2015 Methylmercury Concentrations in Largemouth Bass from the Davis Pond Freshwater Postdiversion Sampling (2007-2009) Methylmercury and associated data in macroinvertebrates from tributaries of Honnedaga Lake and from the Middle Branch Black River in New York. Hydrological, Chemical, and Biological Characterization of the Snake River and Associated Tributaries and Irrigation Drains from River Mile 448 to 346, 2022 Total Mercury and Methylmercury in Riparian Songbirds and Aquatic Invertebrates from the Willamette Valley, Oregon, 2013-2014 Isolation of Methylmercury Using Distillation and Anion-Exchange Chromatography for Isotopic Analyses in Natural Matrices Data Release Mercury and Methylmercury Concentrations in Litterfall Samples Collected at Selected National Atmospheric Deposition Program Sites during 2017 to 2019