Filters: Tags: Denitrification (X) > Categories: Data (X)
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This data set presents attributes of floodplain ecosystem characteristics including floodplain soil denitrification, floodplain soil biogeochemistry, floodplain vegetation, floodplain sedimentation, floodplain and channel morphometry, stream discharge and water quality, floodplain climate, floodplain physiographic region, and catchment land cover. Attributes are associated with 18 floodplains of the Chesapeake Bay watershed. For many of these attributes, mean values are summaries of multiple measurements made within each floodplain site.
Categories: Data;
Tags: Maryland,
Pennsylvania,
USGS Science Data Catalog (SDC),
Virginia,
West Virginia,
The Maumee River transports huge loads of nitrogen (N) and phosphorus (P) to Lake Erie. The increased concentrations of N and P are causing eutrophication of the lake, creating hypoxic zones, and contributing to phytoplankton blooms. It is hypothesized that the P loads are a major contributor to harmful algal blooms that occur in the western basin of Lake Erie, particularly in summer. The Maumee River has been identified by the United States Environmental Protection Agency as a priority watershed where action needs to be taken to reduce nutrient loads. This study quantified rates of biogeochemical processes affecting downstream flux of N and P by 1) measuring indices of potential sediment P retention and 2) measuring...
The Fox River transports elevated loads of nitrogen and phosphorus to Lake Michigan. The increased concentration of N and P causes eutrophication of the lake, creating hypoxic zones and damaging the lake ecosystem.To decrease loading, best management practices (BMPs) have been implemented in the uplands of the basin. Little work has been done, however, to reduce nutrient concentrations in the river. Rivers are capable of removing nutrients through biotic uptake and sediment burial and are able to remove N through denitrification. Identifying and managing these locations of increased nutrient cycling known as “hot spots” may be another mechanism for nutrient mitigation.Our objective was to identify hot spots of N...
Categories: Data;
Tags: Fox River Basin,
Green Bay,
Lake Michigan,
USGS Science Data Catalog (SDC),
agriculture,
The U.S. Geological Survey Toxic Substances Hydrology Program at Cape Cod has been investigating the fate and transport of a treated-wastewater, groundwater contaminant plume. A portion of the contaminated groundwater discharges into Ashumet Pond, a kettle hole, freshwater lake. A study was conducted from June 2013 to June 2015 to document transport, transformation, and discharge of dissolved inorganic nitrogen species (DIN; nitrate, nitrite, and nitrous oxide) from the contaminant plume to the lake, across the groundwater-surface water interface. As part of that study, in October 2014, two natural gradient tracer tests were conducted within the lake bed sediments using nitrite as a reactive tracer and bromide as...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Ashumet Pond,
Denitrification,
Environmental Health,
Geochemistry,
Groundwater-surface water interaction,
Twenty-eight sites that consisted of either predominantly agricultural land in the watershed, predominantly agricultural land in the watershed with natural land cover in the riparian zone, or predominantly natural land cover in the watershed were sampled three times during the growing season.
Groundwater data were collected in the spring and fall of 2008 from three sites representing different geological settings and biogeochemical conditions within the surficial glacial aquifer of Long Island, NY. Investigations were designed to examine the extent to which average vadose zone thickness in contributing watersheds controlled biogeochemical conditions and processes, including dissolved oxygen concentration (DO), oxidation-reduction potential (Eh), dissolved organic carbon concentration (DOC), and microbial dinitrogen (N2) production. Greatest N2 production was observed at the south shore of Long Island, which is characterized by a thin vadose zone, low DO and Eh, and relatively high DOC. Limited N2 production...
Categories: Data;
Types: Citation;
Tags: Geochemistry,
Great South Bay,
Hydrogeology,
Long Island Sound,
Long Island, NY, United States,
The Maquoketa River carries some of the highest sediment and nutrient loads in the Upper Mississippi River, contributing to eutrophication and hypoxic conditions in the Mississippi River and Gulf of Mexico. Floodplains provide the ability to remove and sequester, sediments, nitrogen, phosphorus, and carbon; however effectiveness of floodplains is limited by the extent and connection of the floodplain to the river. The confluence of the Maquoketa and Mississippi Rivers presents a unique study location because the delta at the confluence is heavily managed by a State-Federal-NGO partnership that has already taken action focusing on evaluating the impact of increased connectivity on numerous ecosystem services, including...
Categories: Data;
Tags: Green Island,
Iowa,
Maquoketa River,
USGS Science Data Catalog (SDC),
Upper Mississippi River,
The Maumee River transports huge loads of nitrogen (N) and phosphorus (P) to Lake Erie. The increased concentrations of N and P are causing eutrophication of the lake, creating hypoxic zones, and contributing to phytoplankton blooms. It is hypothesized that the P loads are a major contributor to harmful algal blooms that occur in the western basin of Lake Erie, particularly in summer. The Maumee River has been identified by the United States Environmental Protection Agency as a priority watershed where action needs to be taken to reduce nutrient loads. This study quantified rates of biogeochemical processes affecting downstream flux of N and P by 1) measuring indices of potential sediment P retention and 2) measuring...
Categories: Data,
Data Release - Revised;
Tags: Fort Wayne,
Indiana,
Maumee River,
Maumee River Basin,
Michigan,
Hydraulic connection between channels and floodplains (“connectivity”) is a fundamental determinant of ecosystem function in large floodplain rivers. Factors controlling material processing in these rivers depend not only on the degree of connectivity but also on the sediment conditions, nutrient loads and source. Nutrient cycling in the nutrient-rich upper Mississippi River (MISS) is relatively well studied, while that of less eutrophic tributaries is not (e.g., St Croix River; SACN). We examined components of nitrogen cycling in two floodplain rivers of contrasting nutrient enrichment and catchment land-use to test the hypothesis that N-cycling rates will be greater in the MISS with elevated nutrient-loads and...
Lake Superior is historically a nutrient poor lake that does not typically support significant cyanobacterial blooms. However, the lake has been experiencing an increase in blooms in the western portion of the basin recently. The largest blooms documented have occurred after recent major flooding events, indicating that nutrients transported to the lake during these events may be a source for the blooms. This study looks into the combination of streambed sediment-derived nutrient data during base flow conditions and suspended and settled sediment-derived nutrient data from storm events to provide information about nutrient transformation and storage in the river networks of the Bois Brule River and Siskiwit River...
Categories: Data;
Tags: Aquatic Biology,
USGS Science Data Catalog (SDC),
Upper Wisconsin,
Water Quality,
Western Lake Superior,
The Maumee River transports huge loads of nitrogen (N) and phosphorus (P) to Lake Erie. The increased concentrations of N and P are causing eutrophication of the lake, creating hypoxic zones, and contributing to phytoplankton blooms. It is hypothesized that the P loads are a major contributor to harmful algal blooms that occur in the western basin of Lake Erie, particularly in summer. The Maumee River has been identified by the United States Environmental Protection Agency as a priority watershed where action needs to be taken to reduce nutrient loads. This study quantified rates of biogeochemical processes affecting downstream flux of N and P by 1) measuring indices of potential sediment P retention and 2) measuring...
The U.S. Geological Survey Toxic Substances Hydrology Program at Cape Cod has been investigating the fate and transport of a treated-wastewater, groundwater contaminant plume. A portion of the contaminated groundwater discharges into Ashumet Pond, a kettle hole, freshwater lake. A study was conducted from June 2013 to June 2015 to document transport, transformation, and discharge of dissolved inorganic nitrogen species (DIN; nitrate, nitrite, and nitrous oxide) from the contaminant plume to the lake, across the groundwater-surface water interface. Groundwater, lakewater, lake sediment porewater, and sediment cores were collected and analyzed for DIN constituents as well as functional gene abundance for key N-cycle...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Ashumet Pond, Massachusetts,
Denitrification,
Geochemistry,
Groundwater-surface water interaction,
Hydrogeology,
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