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As an estimate of species-level differences in the capacity to take up different forms of N, we measured plant uptake of 15N-NH4+, 15N-NO3- and 15N, [1]-13C glycine within a set of herbaceous species collected from three alpine community types. Plants grown from cuttings in the greenhouse showed similar growth responses to the three forms of N but varied in the capacity to take up NH4+, NO3- and glycine. Glycine uptake ranged from approximately 42% to greater than 100% of NH4+ uptake; however, four out of nine species showed significantly greater uptake of either NH4+ or NO3- than of glycine. Relative concentrations of exchangeable N at the sites of plant collection did not correspond with patterns of N uptake among...
Recent evidence associates the persistence of invasive plant species with disturbance and fluctuations in distinct forms of mineral N in soils. We conducted soil and hydroponic experiments to investigate the influence of N form and availability on germination and seedling development of 2 invasive annual grasses, cheatgrass (Bromus tectorum) and medusahead (Taeniatherum caput-medusae) and 6 perennial grasses, bluebunch wheatgrass (Pseudoroegneria spicata), crested wheatgrass (Agropyron cristatum x A. desertorum), Sand Hollow and Seaman?s Gulch big squirreltail (Elymus multisetus), and Little Camas and Little Wood bottlebrush squirreltail (E. elymoides ssp. brevifolius and E. elymoides ssp. elymoides, respectively)....
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This product consists of one tabular dataset and associated metadata of water quality information related to rivers, streams, and reservoirs in the Upper Mississippi River watershed between 2012 and 2016. This data release is a part of a national assessment of freshwater aquatic carbon fluxes. Data consist of organic and inorganic carbon related species, carbon dioxide and methane gas fluxes calculated from manual chamber measurements, nitrogen species, carbon isotopes, oxygen isotopes, cations, anions, trace metals, and various in situ measurements including: pH, water temperature, air temperature, barometric pressure, dissolved oxygen, turbidity, fluorescent dissolved organic matter, and specific conductance....
Categories: Data, Project; Types: Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: Carbon, Fluorescent Dissolved Organic Matter (fDOM), Minnesota, Shingobee, Shingobee Headwaters Aquatic Ecosystems Project, All tags...
Freeze–thaw cycles can promote soil N losses as a result of microbial and root cell lysis; however, minimal freeze–thaw effects have typically been observed in studies that have imposed moderate temperature cycles. We conducted laboratory incubations on surface soil (top 3 cm) collected in a temperate old field from late fall through mid-winter to examine how variation in freeze–thaw amplitude, number, timing of collection, and freezing rate altered soil extractable N. We varied freeze–thaw amplitude by imposing minimum cycle temperatures of 0, −1, −2, −5, and −10°C for a series of either one or two cycles and held control samples constant at 3°C. We also examined the effects of freezing rates of 1, 3, and 30°C...
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CalHABMAP provides updates on current algal blooms and facilitates information exchange among HAB researchers, managers and the general public in California. A major component of this program is regional HAB monitoring. Water samples and net tows are collected once per week to monitor for HAB species and naturally occurring algal toxins. Water quality data including temperature, salinity, and nutrients are also collected.
Freeze–thaw cycles can promote soil N losses as a result of microbial and root cell lysis; however, minimal freeze–thaw effects have typically been observed in studies that have imposed moderate temperature cycles. We conducted laboratory incubations on surface soil (top 3 cm) collected in a temperate old field from late fall through mid-winter to examine how variation in freeze–thaw amplitude, number, timing of collection, and freezing rate altered soil extractable N. We varied freeze–thaw amplitude by imposing minimum cycle temperatures of 0, −1, −2, −5, and −10°C for a series of either one or two cycles and held control samples constant at 3°C. We also examined the effects of freezing rates...
Ammonium (NH4 +) is a major constituent of many contaminated groundwaters, but its movement through aquifers is complex and poorly documented. In this study, processes affecting NH4 + movement in a treated wastewater plume were studied by a combination of techniques including large-scale monitoring of NH4 + distribution; isotopic analyses of coexisting aqueous NH4 +, NO3 −, N2, and sorbed NH4 +; and in situ natural gradient 15NH4 + tracer tests with numerical simulations of 15NH4 +, 15NO3 −, and 15N2 breakthrough data. Combined results indicate that the main mass of NH4 + was moving downgradient at a rate about 0.25 times the groundwater velocity. Retardation factors and groundwater ages indicate that much of the...
Ammonium (NH4 +) is a major constituent of many contaminated groundwaters, but its movement through aquifers is complex and poorly documented. In this study, processes affecting NH4 + movement in a treated wastewater plume were studied by a combination of techniques including large-scale monitoring of NH4 + distribution; isotopic analyses of coexisting aqueous NH4 +, NO3 −, N2, and sorbed NH4 +; and in situ natural gradient 15NH4 + tracer tests with numerical simulations of 15NH4 +, 15NO3 −, and 15N2 breakthrough data. Combined results indicate that the main mass of NH4 + was moving downgradient at a rate about 0.25 times the groundwater velocity. Retardation factors and groundwater ages indicate that much of the...
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These metadata sets present the comprehensive geochemical composition of solid and water samples from the site of a 11.4ML (million liters) wastewater spill discovered in January, 2015. Analyses of a pipeline sample (analyses of select analytes), supplied by the North Dakota Department of Health are also included. The spill was near Blacktail Creek, north of Williston, ND. The leak was from a pipeline located approximately 70m from Blacktail Creek. The creek flows 17km before entering the Little Muddy River, a tributary to the Missouri River. The study included samples collected in waters upstream and downstream from Blacktail Creek in February and June 2015, June 2016, and June 2017. These data sets include field...
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Reactive nitrogen is transported from the atmosphere to the landscape as wet and dry deposition that contributes to annual nitrogen loads to the Chesapeake Bay. Estimates of atmospheric inorganic nitrogen deposition to the Chesapeake Bay watershed during 1950 to 2050 are presented, and are based on field measurements, model simulations, statistical relations, and surrogate constituents used for estimates. Wet atmospheric nitrogen deposition has generally been quantified from weekly precipitation sample collections, whereas dry atmospheric nitrogen deposition has been simulated by a model at an hourly time step.
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This data set represents National Atmospheric Deposition Program (NADP) National Trends Network average of annual precipitation-weighted mean atmospheric deposition for seven select constituents from years 1985-2014 compiled for two spatial components of the NHDPlus version 2 data suite (NHDPlusv2) for the conterminous United States; 1) individual reach catchments and 2) reach catchments accumulated upstream through the river network. The seven constiuents presented here are: Calcium, Nitrate, Sulfate, Inorganic Nitrogen, Magnesium, Ammonium, and Chloride. Units are kilograms per hectare. This dataset can be linked to the NHDPlus version 2 data suite by the unique identifier COMID. The source data was produced by...
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This product consists of multiple tabular datasets and associated metadata of water quality information related to rivers, streams, and lakes in the Yukon River watershed between 2014 and 2018. This data release is apart of the National Aeronautics and Space Administration (NASA) funded Arctic-Boreal Vulnerability Experiment (ABoVE) and is an assessment of water quality and greenhouse gas fluxes within the interior of Alaska. Sampling frequency varied across locations, with some sites sampled twice a year or more. Data consist of: organic and inorganic carbon related species, carbon dioxide and methane gas fluxes calculated from manual chamber measurements, nitrogen species, carbon isotopes, oxygen and deuterium...
Groundwater nitrification is a poorly characterized process affecting the speciation and transport of nitrogen. Cores from two sites in a plume of contamination were examined using culture-based and molecular techniques targeting nitrification processes. The first site, located beneath a sewage effluent infiltration bed, received treated effluent containing O2 (> 300 µM) and NH4+ (51–800 µM). The second site was 2.5 km down-gradient near the leading edge of the ammonium zone within the contaminant plume and featured vertical gradients of O2, NH4+, and NO3− (0–300, 0–500, and 100–200 µM with depth, respectively). Ammonia- and nitrite-oxidizers enumerated by the culture-based MPN method were low in abundance at both...
Volume-weighted mean concentrations of nitrate (NO3?), ammonium (NH4+), and sulfate (SO42?) in precipitation were compared at high-elevation sites in Colorado from 1992 to 1997 to evaluate emission source areas to the east and west of the Rocky Mountains. Precipitation chemistry was measured by two sampling methods, the National Atmospheric Deposition Program/National Trends Network (NADP/NTN) and snowpack surveys at maximum accumulation. Concentrations of NO3? and SO42? in winter precipitation were greater on the western slope of the Rockies, and concentrations of NO3? and NH4+ in summer precipitation were greater on the eastern slope. Summer concentrations in general were almost twice as high as winter concentrations....
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This data release provides estimates of monthly wet atmospheric deposition of total inorganic nitrogen (TIN)--the summation of nitrate (NO3) and ammonium (NH4) ions--for the conterminous United States from 1999 through 2020 in units of kilograms nitrogen per square kilometer per month with spatial reference ESPG 4326. The spatial resolution of the gridded data provided in this release is approximately 5 km. The source data used to provide wet deposition estimates include monthly atmospheric concentration data interpolated between National Atmospheric Deposition Program (NADP, 2022) observation stations and monthly precipitation estimates from the National Oceanic and Atmospheric Administration's ClimGrid data (NOAA,...
Nitrification and nitrate reduction were examined in an ephemeral drainage channel receiving discharge from coalbed natural gas (CBNG) production wells in the Powder River Basin, Wyoming. CBNG co-produced water typically contains dissolved inorganic nitrogen (DIN), primarily as ammonium. In this study, a substantial portion of discharged ammonium was oxidized within 50 m of downstream transport, but speciation was markedly influenced by diel fluctuations in dissolved oxygen (> 300 µM). After 300 m of transport, 60% of the initial DIN load had been removed. The effect of benthic nitrogen-cycling processes on stream water chemistry was assessed at 2 locations within the stream channel using acrylic chambers to conduct...
The biogeochemistry at the interface between sediments in a seasonally ponded wetland (slough) and an alluvial aquifer contaminated with landfill leachate was investigated to evaluate factors that can effect natural attenuation of landfill leachate contaminants in areas of groundwater/surface-water interaction. The biogeochemistry at the wetland-alluvial aquifer interface differed greatly between dry and wet conditions. During dry conditions (low water table), vertically upward discharge was focused at the center of the slough from the fringe of a landfill-derived ammonium plume in the underlying aquifer, resulting in transport of relatively low concentrations of ammonium to the slough sediments with dilution and...
Nitrogen translocation was measured in Cladonia portentosa during 2 yr growth in Scottish heathland. Translocation was predicted to occur if N is resorbed from senescent basal tissue and recycled within the thallus. (15)N was introduced into either the lower (TU thalli) or upper (TD thalli) 25 mm of 50-mm-long thalli as (15)N-NH(4) (+), (15)N-NO(3) (-) or (15)N-glycine. Labelled thalli were placed within intact lichen cushions, either upright (TU) or inverted (TD). Vertical distribution of label was quantified immediately following labelling and after 1 and 2 yr. Independently of the form of introduced label, (15)N migrated upwards in TU thalli, with new growth being a strong sink. Sink regions for (15)N during...
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This data release provides quantitative whole rock geochemical results from The Geysers vapor-dominated geothermal field in California. The concentrations of major elements are reported in oxide weight percent by wavelength dispersive x-ray fluorescence (WDXRF), the concentrations for sixty elements are reported in elemental weight percent (pct) or parts per million (ppm) from inductively coupled plasma-optical emission spectrometry-mass spectrometry ICP-OES-MS analysis, mercury is reported in ppm by cold vapor atomic absorption spectrometry (CVAAS), and ammonium in ppm from automated colorimetry analysis. The analyses show significant enrichment of volatile elements and elements such as sulfur, boron, arsenic,...
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This record describes a series of comma separated files containing mean rates of monthly total nitrogen (TN), ammonium (NH4), and nitrate atmospheric (NO3) wet deposition attributed to NHDPlus version 2 (NHDv2, Moore and Dewald, 2016)) catchments for the period of record, October, 2006 to September, 2017. Units are in kilograms per square kilometer (kg/km2).
map background search result map search result map Attributes for NHDPlus Version 2.1 Catchments and Modified Routing of Upstream Watersheds for the Conterminous United States: National Atmospheric Deposition Program (NADP) National Trends Network (NTN) 1985-2014 Water quality, quantity, and gas fluxes of the Upper Mississippi River basin (WY 2012-2016) Water quality and gas fluxes of Interior Alaska (2014-2018) Estimates of atmospheric inorganic nitrogen deposition to the Chesapeake Bay watershed, 1950-2050 Geochemistry Data from Samples Collected in 2015-2017 to study an OG wastewater spill in Blacktail Creek, North Dakota Harmful Algal Bloom (HAB) data collected by the Scripps Institution of Oceanography and made available by the Southern California Coastal Observing System (SCCOOS) Mean monthly atmospheric wet deposition attributed to NHDplus version 2, October 2006 through September 2017 Monthly inorganic nitrogen atmospheric wet deposition estimates for the conterminous United States, 1999 through 2020 The major, minor, and trace element geochemistry of mineral scales from The Geysers geothermal field, California, USA The major, minor, and trace element geochemistry of mineral scales from The Geysers geothermal field, California, USA Water quality and gas fluxes of Interior Alaska (2014-2018) Water quality, quantity, and gas fluxes of the Upper Mississippi River basin (WY 2012-2016) Estimates of atmospheric inorganic nitrogen deposition to the Chesapeake Bay watershed, 1950-2050 Harmful Algal Bloom (HAB) data collected by the Scripps Institution of Oceanography and made available by the Southern California Coastal Observing System (SCCOOS) Monthly inorganic nitrogen atmospheric wet deposition estimates for the conterminous United States, 1999 through 2020 Attributes for NHDPlus Version 2.1 Catchments and Modified Routing of Upstream Watersheds for the Conterminous United States: National Atmospheric Deposition Program (NADP) National Trends Network (NTN) 1985-2014 Mean monthly atmospheric wet deposition attributed to NHDplus version 2, October 2006 through September 2017