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Lake Powell retains most of the phosphorus that it receives, leading to downstream phosphorus limitation. These data were compiled to examine controls on phosphorus cycling below Lake Powell in the Colorado River and from storm inputs from the Paria River. Objectives of our study were to determine how several forms of phosphorus, both organic and inorganic, were cycled under varying dissolved oxygen concentrations and pH, reflecting the range of values observed in the river over the years. These data represent nitrogen, phosphorus, calcium, and carbon concentrations, water quality parameters (pH, dissolved oxygen, temperature), sediment composition, total protein, and extracellular enzyme activity (alkaline phosphatase)....
Categories: Data; Tags: Aquatic Biology, Arizona, Colorado River, Ecology, Geochemistry, All tags...
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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...
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These data were compiled for a study that investigated the effects of drought seasonality and plant community composition in a dryland ecosystem. In 2015 U.S. Geological Survey ecologists recorded vegetation and soil moisture data in 36 experimental plots which manipulated precipitation in two plant community types. The experiment consisted of three precipitation treatments: control (ambient precipitation), cool-season drought (-66% ambient precipitation November-April), and warm-season drought (-66% ambient precipitation May-October), applied in two plant communities (perennial grasses with or without a large shrub, Ephedra viridis) over a three-year period. These data were collected from 2015 to 2022 near Canyonlands...
Categories: Data; Tags: Achnatherum hymenoides, Botany, C3 photosynthesis, C4 photosynthesis, Canyonlands National Park, All tags...
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Nitrogen, phosphorus, and suspended-sediment loads, and changes in loads, in rivers across the Chesapeake Bay watershed have been calculated using monitoring data from the nine Chesapeake Bay River Input Monitoring (RIM) stations for the period 1985 through 2015. Nutrient and suspended-sediment loads and changes in loads were determined by applying a weighted regression approach called WRTDS (Weighted Regression on Time, Discharge, and Season). Yields (represents the mass of constituent transported from a unit area of a given watershed) are used to compare the export loads from one basin to another. Yield results are obtained by dividing the annual load (pounds) of a given constituent by the respective watershed...
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This USGS Data Release represents the data used to develop multiple linear regression models for estimating the loads of total nitrogen in small streams. Recursive partitioning and random forest regression were used to assess 85 geospatial, environmental, and watershed variables across 636 small (less than 585 square kilometers) watersheds to determine which variables are fundamentally important to the estimation of annual loads of total nitrogen. These data support the following publication: Kronholm, S.C., Capel, P.D., and Terziotti, Silvia, 2016, Statistically extracted fundamental watershed variables for estimating the loads of total nitrogen in small streams: Environmental Modeling and Assessment, 10 p., http://dx.doi.org/10.1007/s10666-016-9525-3.
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These data were compiled to improve our understanding of how water, carbon (C), nitrogen (N), and phosphorus (P) interact to regulate below ground carbon cycling. Objective(s) of our study were to evaluate how soil heterotrophic carbon cycling responded to inputs of water, C, N, and P individually and interactively on the Colorado Plateau. These data represent soil microbial and CO2 respiration responses to amendments of carbon, nitrogen, phosphorous, and water. Soils were collected at a study site located in Arches National Park in southeastern Utah on 14 August 2017 and again on 17 July 2018 from the upper 10 cm of the soil profile in open spaces among plant canopies after the biological soil crust layer (< 1...
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Nitrogen, phosphorus, and suspended-sediment loads, and changes in loads, in rivers across the Chesapeake Bay watershed have been calculated using monitoring data from the Chesapeake Bay Nontidal Network (NTN) stations for the period 1985 through 2018 Nutrient and suspended-sediment loads and changes in loads were determined by applying a weighted regression approach called WRTDS (Weighted Regression on Time, Discharge, and Season). A recently published extension of WRTDS allows users to separate these estimates into high- and low-flow conditions. This data release contains (1) a table of daily high- and low-flow concentration and load estimates for NTN stations between 1985 - 2018 and (2) an R file that contains...
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This data set consists of monthly averages of soil and litter properties. Rows are grouped in the following order: year, month, vegetation type, plot ID. Within a single month five plots were sampled within each of the 2 vegetation types (10 plots total). Columns F+ represent individual measurements.
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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...
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The accretion history of fringing salt marshes located on the south shore of Cape Cod is reconstructed from sediment cores collected in low and high marsh vegetation zones. These marshes are micro-tidal, with a mean tidal range of 0.442 m. Their location within protected embayments and the absence of large rivers results in minimal sediment supply and a dominance of organic matter contributions to sediment peat. Age models based on 210-lead and 137-cesium are constructed to evaluate how vertical accretion and carbon burial rates have changed over the past century. The continuous rate of supply age model was used to age date 11 cores (10 low marsh and 1 high marsh) across four salt marshes. Both vertical accretion...
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This dataset includes input and output data from streamflow and water-quality regression models used to characterize streamflow and water-quality conditions in the Upper White River Basin, Colorado, from 2000 to 2020. All input data, including discrete and continuous streamflow records and discrete concentrations of inorganic nitrogen, total nitrogen, and total phosphorus, were compiled from the U.S. Geological Survey (USGS) National Water Information System (NWIS) database. Input data were used in multiple models including Maintenance of Variance Extension Type 2 (MOVE.2) and Weighted Regressions on Time, Discharge, and Season (WRTDS) to estimate continuous streamflow records, daily concentrations and loads, and...
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This dataset includes high-frequency sensor data collected during four consecutive summers from buoys deployed at main channel and backwater sites in Pool 8 of the Upper Mississippi River from 2015-2018. It also includes the event-specific concentration-discharge metrics (hysteresis and slope) calculated by combining the water quality sensor data with discharge data from a nearby USGS gage in Winona, MN (05378500). High-frequency sensor data were collected using water quality buoys (PISCES monitoring platforms; EMM350 Water Monitoring Pontoon Platform | ysi.com | ysi.com; Yellow Springs, Ohio) set up with EXO2 Multiparameter Sondes (YSI, Inc, Yellow Springs, Ohio) to monitor hourly or bi-hourly concentrations of...
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Nitrogen, phosphorus, and suspended-sediment loads, and changes in loads, in rivers across the Chesapeake Bay watershed have been calculated using monitoring data from the Chesapeake Bay Nontidal network (NTN) stations for the period 1985 through 2018. Nutrient and suspended-sediment loads and changes in loads were determined by applying a weighted regression approach called WRTDS (Weighted Regression on Time, Discharge, and Season). Yields (represents the mass of constituent transported from a unit area of a given watershed) are used to compare the export loads from one basin to another. Yield results are obtained by dividing the annual load (pounds) of a given constituent by the respective watershed area (acres)...
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This child page contains 34 csv files, site_qw_nuts, which contain observations of nitrate plus nitrite as nitrogen (npnN), total nitrogen (TN), total phosphorus (TP) for each site . Each file includes date of observation, measured value of water-quality constituent, remark code for the measured value, and site name. Availability of observations of water-quality constituents depended upon collecting agency and varied by site and constituent. Not all sites had observations for all constituents. The format of the csv file (date format and column headings) is designed to meet the specific requirements of file format for R-QWTREND. If csv files are opened directly in excel, the format of the data can change. To ensure...
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This U.S. Geological Survey data release presents tabular data on nitrogen concentrations and loads for multiple nitrogen species, and river discharge data used in the analysis of data collected from October 1994 to September 2016. Data on flow and nitrogen concentrations were analyzed using the USGS EGRET R package, and the method of WRTDS (Weighted Regression on Time Discharge and Season). Data and outputs summarized are for water-quality data collected from 18 water-quality monitoring stations in the Long Island Sound watershed. Specific data in tabular format for this release include: calculated annual nitrogen concentration and loads, calculated annual flow-normalized nitrogen concentrations and loads by water...
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This data release consists of the data used to develop SPAtially Referenced Regression On Watershed(SPARROW) attributes models for estimating loads of total phosphorus and total nitrogen in Tennessee streams. These data support the publication containing the Tennessee SPARROW models results (Hoos and others, 2019) and include model input used in the South Atlantic-Gulf Drainages and Tennessee River Basin (SAGT) nutrient SPARROW models (Hoos and McMahon, 2009; Garcia and others, 2011) as well as model input for river basins in Tennessee not included in the domain of the published SAGT SPARROW models. Also included in this data release are model coefficients, the software required to execute the Tennessee SPARROW...
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This data release consists of the data used to develop SPAtially Referenced Regression On Watershed(SPARROW) attributes models for estimating loads of total phosphorus and total nitrogen in Tennessee streams. These data support the publication containing the Tennessee SPARROW models results (Hoos and others, 2019) and include model input used in the South Atlantic-Gulf Drainages and Tennessee River Basin (SAGT) nutrient SPARROW models (Hoos and McMahon, 2009; Garcia and others, 2011) as well as model input for river basins in Tennessee not included in the domain of the published SAGT SPARROW models. Also included in this data release are model coefficients, the software required to execute the Tennessee SPARROW...
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Permafrost (perennially frozen) and active-layer (seasonally thawed) soils varying in soil carbon (C) and nitrogen (N) content and radiocarbon age were collected from three sites in interior Alaska to determine potential release of dissolved organic carbon (DOC), total dissolved N (TDN), dissolved organic nitrogen (DON), and dissolved inorganic nitrogen (DIN) upon thaw. Soil cores were cut into 15 cm thick sections, and deep active-layer (15-30 cm above the permafrost boundary) and shallow permafrost (15-30 cm below the permafrost boundary) sections were thawed and leached with deionized water. Soil leachates were analyzed for DOC, TDN, nitrate (NO3-), and ammonium (NH4+) concentrations, dissolved organic matter...
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Nitrogen, phosphorus, and suspended-sediment loads, and changes in loads, in major rivers across the Chesapeake Bay watershed have been calculated using monitoring data from the Chesapeake Bay River Input Monitoring Network (RIM) stations for the period 1985 through 2017. Nutrient and suspended-sediment loads and changes in loads were determined by applying a weighted regression approach called WRTDS (Weighted Regression on Time, Discharge, and Season). The load results represent the total mass of nitrogen, phosphorus, and suspended sediment that was exported from each of the RIM watersheds.
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This data release consists of the data used to develop SPAtially Referenced Regression On Watershed(SPARROW) attributes models for estimating loads of total phosphorus and total nitrogen in Tennessee streams. These data support the publication containing the Tennessee SPARROW models results (Hoos and others, 2019) and include model input used in the South Atlantic-Gulf Drainages and Tennessee River Basin (SAGT) nutrient SPARROW models (Hoos and McMahon, 2009; Garcia and others, 2011) as well as model input for river basins in Tennessee not included in the domain of the published SAGT SPARROW models. Also included in this data release are model coefficients, the software required to execute the Tennessee SPARROW...


map background search result map search result map Data on annual total nitrogen loads and watershed characteristics used to develop a method to estimate the total nitrogen loads in small streams Effects of Flood Inundation and Invasion by Phalaris arundinacea on Nitrogen Cycling in an Upper Mississippi River Floodplain Forest data Chesapeake Bay Nontidal Network 2005-2014: Average Yields Collection, analysis, and age-dating of sediment cores from salt marshes on the south shore of Cape Cod, Massachusetts, from 2013 through 2014 Chesapeake Bay River Input Monitoring Network 1985-2017: Annual loads Dissolved organic carbon and nitrogen release from boreal Holocene permafrost and seasonally frozen soils of Alaska Names of 10-digit hydrologic unit code (HUC10) watersheds in the state of Tennessee Shapefile of stream reaches used in Tennessee SPARROW models Great Lakes Restoration Initiative Project 49 Fox River Basin 2016 and 2017 Data Nitrogen concentrations and loads and seasonal nitrogen loads in selected Long Island Sound tributaries, water years 1995-2016 Scenario calculator for Tennessee SPARROW nutrient models Chesapeake Bay Nontidal Network 1985-2018: Average annual yields Water-quality data for nitrate plus nitrite, total nitrogen, and total phosphorus for sites in Red River of the North basin, 1970–2017 Chesapeake Bay Nontidal Network 1985 – 2018: Daily High-Flow and Low-Flow Concentration and Load Estimates (ver. 1.1, November 2021) CO2 concentrations and microbial biomass data derived from incubation experiments on soils collected at Arches National Park in 2017 and 2018 Input and ouput data from streamflow and water-quality regression models used to characterize streamflow and water-quality conditions in the Upper White River Basin, Colorado, from 2000-2020 Great Lakes Restoration Initiative: Nutrient cycling in riverbed sediment in the Maumee River Basin, 2021 Data (ver. 2.0, March 2024) Phosphorus, nitrogen, carbon, calcium, pH, and dissolved oxygen data from incubations of Colorado River water and sediment and associated ambient river water measurements Continuous water quality sensor data from the main channel and a backwater of the Upper Mississippi River from 2015-2018 Plant composition, shrub biomass, and soil biogeochemistry from an experimental drought treatment on the Colorado Plateau Plant composition, shrub biomass, and soil biogeochemistry from an experimental drought treatment on the Colorado Plateau Collection, analysis, and age-dating of sediment cores from salt marshes on the south shore of Cape Cod, Massachusetts, from 2013 through 2014 Input and ouput data from streamflow and water-quality regression models used to characterize streamflow and water-quality conditions in the Upper White River Basin, Colorado, from 2000-2020 Continuous water quality sensor data from the main channel and a backwater of the Upper Mississippi River from 2015-2018 Nitrogen concentrations and loads and seasonal nitrogen loads in selected Long Island Sound tributaries, water years 1995-2016 Great Lakes Restoration Initiative: Nutrient cycling in riverbed sediment in the Maumee River Basin, 2021 Data (ver. 2.0, March 2024) Phosphorus, nitrogen, carbon, calcium, pH, and dissolved oxygen data from incubations of Colorado River water and sediment and associated ambient river water measurements Dissolved organic carbon and nitrogen release from boreal Holocene permafrost and seasonally frozen soils of Alaska Great Lakes Restoration Initiative Project 49 Fox River Basin 2016 and 2017 Data Water-quality data for nitrate plus nitrite, total nitrogen, and total phosphorus for sites in Red River of the North basin, 1970–2017 Chesapeake Bay Nontidal Network 2005-2014: Average Yields Chesapeake Bay River Input Monitoring Network 1985-2017: Annual loads Chesapeake Bay Nontidal Network 1985 – 2018: Daily High-Flow and Low-Flow Concentration and Load Estimates (ver. 1.1, November 2021) Chesapeake Bay Nontidal Network 1985-2018: Average annual yields Names of 10-digit hydrologic unit code (HUC10) watersheds in the state of Tennessee Shapefile of stream reaches used in Tennessee SPARROW models Scenario calculator for Tennessee SPARROW nutrient models Data on annual total nitrogen loads and watershed characteristics used to develop a method to estimate the total nitrogen loads in small streams