Search Results - "Ullman, William J."

Direct Determination of Total and Fresh Groundwater Discharge and Nutrient Loads from a Sandy Beachface at Low Tide (Cape Henlopen, Delaware) by Hays, Rebecca L., Ullman, William J.

“…Total groundwater discharge from a sandy seepage site to the Delaware Bay at Cape Henlopen, Delaware, was determined together with the associated nutrient…”
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Ecological consequences of ground water discharge to Delaware Bay, United States by Miller, D.C, Ullman, W.J

“…Submarine ground water discharge to the ocean has the potential to create estuarine conditions near the point of discharge, thereby dramatically altering local…”
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Coupled surface-subsurface hydrologic measurements reveal infiltration, recharge, and discharge dynamics across the swash zone of a sandy beach by Heiss, James W., Puleo, Jack A., Ullman, William J., Michael, Holly A.

“…Swash‐groundwater interactions affect the biogeochemistry of beach aquifers and the transport of solutes and sediment across the beachface. Improved…”
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Swash zone moisture dynamics and unsaturated infiltration in two sandy beach aquifers by Heiss, James W., Ullman, William J., Michael, Holly A.

“…The intertidal zone of coastal aquifers is a dynamic region of mixing between saline surface water and fresh groundwater. Groundwater circulation in this zone…”
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Atmospheric nitrogen inputs to the Delaware Inland Bays: the role of ammonia by Scudlark, Joseph R., Jennings, Jennifer A., Roadman, Megan J., Savidge, Karen B., Ullman, William J.

“…A previous assessment of nitrogen loading to the Delaware Inland Bays indicates that atmospheric deposition provides 15–25% of the total, annual N input to…”
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Hydrophysical and Hydrochemical Controls of Cyanobacterial Blooms in Coursey Pond, Delaware (USA) by Andres, A. Scott, Main, Christopher R., Pettay, D. Tye, Ullman, William J.

“…Noxious cyanobacterial blooms are common in many ponds in the mid‐Atlantic Coastal Plain. In Delaware, blooms normally occur between July and October, yet no…”
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Hydrologic Shifts Create Complex Transient Distributions of Particulate Organic Carbon and Biogeochemical Responses in Beach Aquifers by Kim, Kyra H., Michael, Holly A., Field, Erin K., Ullman, William J.

“…Biogeochemical reactions within intertidal zones of coastal aquifers have been shown to alter the concentrations of terrestrial solutes prior to their…”
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Assessment of the suitability of Durafet-based sensors for pH measurement in dynamic estuarine environments by Gonski, Stephen F., Cai, Wei-Jun, Ullman, William J., Joesoef, Andrew, Main, Christopher R., Pettay, D. Tye, Martz, Todd R.

“…The suitability of the Honeywell Durafet to the measurement of pH in productive, high-fouling, and highly-turbid estuarine environments was investigated at the…”
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Spatial Patterns of Groundwater Biogeochemical Reactivity in an Intertidal Beach Aquifer by Kim, Kyra H., Heiss, James W., Michael, Holly A., Cai, Wei‐Jun, Laattoe, Tariq, Post, Vincent E. A., Ullman, William J.

“…Beach aquifers host a dynamic and reactive mixing zone between fresh and saline groundwater of contrasting origin and composition. Seawater, driven up the…”
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In situ response of bay productivity to nutrient loading from a small tributary: The Delaware Bay-Murderkill Estuary tidally-coupled biogeochemical reactor by Voynova, Yoana G., Lebaron, Karine C., Barnes, Rebecca T., Ullman, William J.

“…A small, turbid and nutrient-rich tributary, the Murderkill Estuary, and a large estuarine ecosystem, the Delaware Bay, are tightly linked and form an…”
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Seasonal and Spatial Production Patterns of Dissolved Inorganic Carbon and Total Alkalinity in a Shallow Beach Aquifer by Kim, Kyra H., Heiss, James W., Michael, Holly A., Ullman, William J., Cai, Wei-Jun

“…Dissolved inorganic carbon (DIC) and total alkalinity (Alk T ) fluxes to the nearshore ocean can directly impact the rates of primary production, coral reef…”
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Water Level and Velocity Characteristics of a Salt Marsh Channel in the Murderkill Estuary, Delaware by Dzwonkowski, Brian, Wong, Kuo-Chuin, Ullman, William J

“…Dzwonkowski, B.; Wong, K.-C., and Ullman, W.J., 2014. Water level and velocity characteristics of a salt marsh channel in the Murderkill estuary, Delaware…”
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Dissolved Nutrient Fluxes through a Sandy Estuarine Beachface (Cape Henlopen, Delaware, U.S.A.): Contributions from Fresh Groundwater Discharge, Seawater Recycling, and Diagenesis by Rebecca L. Hays, Ullman, William J.

“…The sandy beachface at Cape Henlopen, Delaware, receives dissolved nutrient inputs from fresh upland groundwater and estuarine seawater and exports nutrients…”
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Groundwater mixing, nutrient diagenesis, and discharges across a sandy beachface, Cape Henlopen, Delaware (USA) by Ullman, William J, Chang, Bonnie, Miller, Douglas C, Madsen, John A

“…Groundwater and associated nutrients discharge from the beachface to the Delaware Estuary at Cape Henlopen, Delaware, and appear to contribute significantly to…”
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Intra- and inter-annual trends in phosphorus loads and comparison with nitrogen loads to Rehoboth Bay, Delaware (USA) by Volk, Jennifer A., Scudlark, Joseph R., Savidge, Karen B., Andres, A. Scott, Stenger, Robert J., Ullman, William J.

“…Monthly phosphorus loads from uplands, atmospheric deposition, and wastewater to Rehoboth Bay (Delaware) were determined from October 1998 to April 2002 to…”
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Direct determination of iodide in seawater by cathodic stripping square wave voltammetry by Luther, George W, Swartz, Christina Branson, Ullman, William J

“…A procedure for the direct determination of iodide in seawater is described. By use of cathodic stripping square wave voltammetry, it is possible to determine…”
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Simulated impacts of artificial groundwater recharge and discharge on the source area and source volume of an Atlantic Coastal Plain stream, Delaware, USA by Kasper, Joshua W, Denver, Judith M, McKenna, Thomas E, Ullman, William J

“…A numerical groundwater-flow model was used to characterize the source area and volume of Phillips Branch, a baseflow-dominated stream incising a highly…”
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Dissolved Nutrient Fluxes through a Sandy Estuarine Beachface (Cape Henlopen, Delaware, U.S.A.): Contributions from Fresh Groundwater Discharge, Seawater Recycling, and Diagenesis by Hays, Rebecca L., Ullman, William J.

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The temperature dependence of bytownite feldspar dissolution in neutral aqueous solutions of inorganic and organic ligands at low temperature (5–35°C) by Welch, Susan A., Ullman, William J.

“…The temperature dependence of silica release from bytownite, a Ca–Al-rich feldspar, was determined in solutions of inorganic and organic ligands at neutral pH…”
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Understanding the dynamic response of Durafet-based sensors: A case study from the Murderkill Estuary-Delaware Bay system (Delaware, USA) by Gonski, S. Fisher, Ullman, William J., Pettay, D. Tye, Booksh, Karl S., Martz, Todd R., Luther, George W., Cai, Wei-Jun

“…The use of Durafet-based sensors has proliferated in recent years, but their performance in estuarine waters (salinity < 20) where rapid changes in temperature…”
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