Filters: Tags: atmospheric deposition (chemical & particulate) (X)8 results (9ms)
Seasonal Atmospheric Nitrate and Ammonium Deposition along an Elevation Gradient in the Colorado Front Range using Ion Exchange Resin Columns (2018-2019)
Atmospheric deposition of reactive nitrogen (Nr) due to human activities can have measurable effects on ecosystem processing and export of nutrients, groundwater and surface-water quality. Rates of Nr deposition to lower-elevation forests immediately adjacent to the Denver/Boulder urban area, however, have only recently been measured. The focus of this study was to determine the extent of urban and agricultural N pollution transport to the Colorado Front Range. In conjunction with the Network for Urban Atmospheric Nitrogen Chemistry (NUANC) and the National Atmospheric Deposition Program (NADP), we measured wet-plus-dry Nr deposition and evaluated spatial and seasonal variations in N deposition along an elevational...
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.
These data are annual aeolian dust deposition calculations from vertical deposition at seven locations near the vicinity of Moab, Utah covering the period from 1999 to 2020. Data were collected by the U.S. Geological Survey Geosciences and Environmental Change Science Center (Denver, Colorado) and Southwest Biological Science Center (Moab, Utah) to "monitor sediment characteristics at sites selected to illuminate the relations between dust sources, present climate, and land use patterns" (Reheis 2003). The sites selected represent various land uses and land ownership including private land, multiple-use public lands, and restricted use National Parks. From 1999-2013 samples were sent to the Geosciences and Environmental...
Estimates of inorganic nitrogen deposition from precipitation for selected Chesapeake Bay Watersheds
This dataset contains estimates of the yearly sum of nitrogen atmospheric deposition of inorganic nitrogen in selected Chesapeake Bay watersheds from 1985-2012. Data for 1985-2012 were downloaded from the National Atmospheric Deposition Program.
Using wildland fire tracer molecules to investigate fire frequency and vegetative combustion sources archived in the Juneau Icefield of Alaska
The past decade includes some of the most extensive boreal forest fires in the historical record. Environmental drivers include warming temperatures, changing precipitation patterns, desiccation of thick organic soil layers, and increased ignition frequency from lightning. Wildland fires produce smoke aerosols that can travel thousands of kilometers, before blanketing the surfaces on which they fall, such as the Juneau Icefield of Alaska. This data release presents chemical constituent and physical particulate results from investigations of wildland fire smoke deposits and other atmospheric deposition characteristics stored in layers of ice in the Juneau Icefield of Alaska, USA (Tables 1 and 2). We drilled a series...
The data represent a shallow mercury chronology using sediment core from a playa lake system situated in a high-altitude setting in northwest Argentina. Archive samples were used from sediment core (LP07-1A) that was collected from a location (lat -22.362100°, lon -66.003600°) in the center of the playa-lake Laguna de Pozuelos in the dry season of 2007, when the water level was 2 to 3 cm. The samples were taken over 1 to 2 cm intervals and had been dried and homogenized. Sediment total mercury analyses were conducted by digesting sediment (0.30 g) in boiling concentrated nitric/sulfuric acid (ratio 3:1), followed by 12 hour oxidation with bromine monochloride, tin chloride reduction, gold amalgamation, and detection...
Urban sediment and fallout radionuclide input characteristics of Dead Run watershed in Catonsville, Maryland for 2017-2018 (ver. 1.1, March 2020)
This metadata record documents two comma delimited tables that contain information on fallout radionuclides and urban sediments within Dead Run watershed in Catonsville, Baltimore County, Maryland. Measurements include radiological activity for rainwater and sediment samples, sediment particle size information, suspended sediment concentration measurements, elemental composition of sediments, and sediment yields of paved surfaces. First posted - November 13, 2019 (available from author) Revised - March 19, 2020 (version 1.1)
Eolian dust constitutes most of the pedogenic material in latePleistocene and Holocene soils of many arid regions. Comparison ofthe compositions and influx rates of modern dust with the eoliancomponent of dated soils at 24 sites in southern Nevada andCalifornia yields information on: (1) the composition and influxrate of dust in late Pleistocene and Holocene soils, (2) paleoclimateand its effects on the genesis of aridic soils, especially withregard to "dust events", (3) the timing and relative contribution ofdust from playa sources versus alluvial sources, and (4) the effectsof accumulation of fines in soil horizons. The A and B horizons ofsoils formed on gravelly alluvial-fan deposits in the study area aresimilar...