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Lake Erie walleye (Stizostedion vitreum) recruitment fluctuates annually and depends partially on their diet and growth during their first year of life. To determine how age-0 walleye have responded to changes in prey species and abundance, larval and young of year walleye were collected from western Lake Erie in 2019 and 2014. Larval and young of year fish stomachs were extracted and dissected, with prey contents removed for later identification. All prey contents were identified to the lowest possible taxonomic level using a dissecting microscope and counted, with up to 20 prey items from each taxa per fish measured (0.01 mm) using a digital computer image analysis system. Zooplankton prey items were identified...
Nitrapyrin is a nitrification inhibitor that is co-applied with N-fertilizer in agroecosystems. Over the course of one year (March 2016 to June 2017), 192 water samples from seven streams across Iowa and Illinois were analyzed for nitrapyrin, its degradate 6-chloropicolinic acid (6-CPA), and three widely used herbicides acetochlor, atrazine, and metolachlor. Additional environmental samples were collected and analyzed in spring 2017: 63 water samples from eight subsurface drains, and 33 soil samples from a field in Iowa that received direct application of nitrapyrin (only for nitrapyrin and herbicides). Nitrapyrin was detected in all seven streams (56% detection) with concentrations ranging from 4 to 1,200 ng/L;...
We determined acute and chronic toxicity of sodium chloride (NaCl) and sodium sulfate (Na2SO4) to up to 7 freshwater species of different taxa in a hardness water of 40 mg/L as CaCO3 and evaluated the effect of 4 hardness waters (15, 30, 60, and 120 mg/L as CaCO3) on acute toxicity of NaCl and Na2SO4 to 3 sensitive species tested in the acute exposures. This data release reports results from acute and chronic exposures with Ceriodaphnia dubia (cerios), Chironomus dilutus (midge), Hyalella azteca (amphipod), Hyla versicolor (gray treefrog), Lampsilis abrupta (pink mucket), Lampsilis siliquoidea (fatmucket), and Pimephales promelas (fathead minnow. Date include survival, size, and other endpoints and associated water...
Categories: Data;
Tags: Aquatic Biology,
Columbia Environmental Research Center,
USGS Science Data Catalog (SDC),
aquatic biology,
bioassays,
Recent declines in Lake Whitefish population abundance has prompted research to identify underlying mechanisms controlling survival of early life stages in the Great Lakes. In Lake Erie, the recruitment bottleneck window determining year class strength of Lake Whitefish occurs during the first growing season, suggesting that availability of prey could be controlling year class strength. Therefore, spatial and seasonal larval Lake Whitefish distribution, diet, and environmental zooplankton (potential prey) were collected to evaluate larval Lake Whitefish diets at 31 locations in the western basin during 2017, 2018, and 2021. We removed gut tracks of larval lake whitefish and identified diet items to lowest possible...
Four dichloroacetamide herbicide safeners (AD-67, benoxacor, dichlormid, and furilazole) and two co-applied herbicides (acetochlor and metolachlor) were measured in water samples from 7 streams across Iowa and Illinois. Iowa water samples were collected from March 2016 to June 2017, and Illinois water samples were collected from September 2016 to June 2017. The compounds studied are applied to corn, and Iowa and Illinois are the two largest corn producing states in the U.S. The seven stream sites are all adjacent to agricultural fields in corn production. Water samples (1-L) were collected in amber glass bottles using a grab or depth weighted approach. With the exception of one site, Iowa River at Wapello (USGS...
Categories: Data;
Tags: Corn Belt region,
Environmental Health,
Illinois,
Iowa,
USGS Science Data Catalog (SDC),
Nitrapyrin, a nitrification inhibitor, 6-CPA, a nitrapyrin degradate, and three co-applied herbicides (acetochlor, atrazine, and metolachlor) were measured in surface drains from eights sites in Illinois. Water samples were collected from April to June 2017. The compounds studied are applied to corn, Illinois is one of the largest corn producing states in the U.S. Water samples (1-L) were collected in amber glass bottles using a grab or depth weighted approach. Water samples were filtered (0.7 micrometers), extracted via solid phase extraction (Oasis® MAX cartridge), and analyzed (nitrapyrin and herbicides by gas chromatography with mass-spectrometry; 6-CPA by liquid chromatography tandem mass-spectrometry).
Categories: Data;
Tags: Corn Belt region,
Illinois,
United States,
contaminant transport,
ecotoxicity,
Nitrapyrin, a nitrification inhibitor, 6-CPA, a nitrapyrin degradate, and three co-applied herbicides (acetochlor, atrazine, and metolachlor) were measured in water samples from seven streams across Iowa and Illinois. Iowa water samples were collected from March 2016 to June 2017, and Illinois water samples were collected from September 2016 to June 2017. The compounds studied are applied to corn, and Iowa and Illinois are the two largest corn producing states in the U.S. The seven stream sites are all adjacent to agricultural fields in corn production. Water samples (1-L) were collected in amber glass bottles using a grab or depth weighted approach. With the exception of one site, Iowa River at Wapello (USGS Site...
Nitrapyrin, a nitrification inhibitor, and three co-applied herbicides (acetochlor, atrazine, and metolachlor) were measured in soil samples from an agricultural field in Iowa. Samples were collected from three locations in the field before and after nitrapyrin application in April-May 2017. Soils were collected using a 5-inch pipe that was hammered into the ground. Soil samples were extracted using pressurized solvent extraction (with dichloromethane), clean-up via solid phase extraction (carbon and alumina sorbents), and analyzed by gas chromatography with mass-spectrometry.
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