John Crusius (Former Employee)
Science and Products
Filter Total Items: 40
Continuous resistivity profiling data from the upper Neuse River Estuary, North Carolina, 2004-2005 Continuous resistivity profiling data from the upper Neuse River Estuary, North Carolina, 2004-2005
The Neuse River Estuary in North Carolina has suffered impacts of eutrophication in recent years. As part of a larger project to better constrain nutrient budgets in the estuary, field investigations were performed to study occurrence and discharge of fresh and brackish ground water and nutrients beneath the estuary itself (fig. 1). A Continuous Resistivity Profiling (CRP) system...
Authors
VeeAnn A. Cross, John F. Bratton, Emile M. Bergeron, Jeff K. Meunier, John Crusius, Dirk Koopmans
Submarine ground-water discharge: nutrient loading and nitrogen transformations Submarine ground-water discharge: nutrient loading and nitrogen transformations
Eutrophication of coastal waters due to nonpoint source land-derived nitrogen (N) loads is a worldwide phenomenon and perhaps the greatest agent of change altering coastal ecology (National Research Council, 2000; Howarth and others, 2000). Within the United States, a majority of estuaries have been determined to be moderately to severely impaired by eutrophication associated with...
Authors
Kevin D. Kroeger, Peter W. Swarzenski, John Crusius, John F. Bratton, Matthew A. Charette
Processes influencing the transport and fate of contaminated sediments in the coastal ocean — Boston Harbor and Massachusetts Bay Processes influencing the transport and fate of contaminated sediments in the coastal ocean — Boston Harbor and Massachusetts Bay
No abstract available.
Authors
P. Soupy Alexander, Dann S. Blackwood, Jonathan Borden, Michael A. Casso, John Crusius, Joanne Goudreau, Linda H. Kalnejais, Paul J. Lamothe, William R. Martin, Marinna A. Martini, Sandra M. Milbert, Richard R. Rendigs, Frederick L. Sayles, Richard P. Signell, Page C. Valentine, John C. Warner
Putting radon to work: identifying coastal ground-water discharge sites Putting radon to work: identifying coastal ground-water discharge sites
No abstract available.
Authors
John Crusius, John F. Bratton, Matt Charette
Coastal iron fluxes to surface waters of the NE Pacific: A driver of the marine ecosystem and carbon cycle Coastal iron fluxes to surface waters of the NE Pacific: A driver of the marine ecosystem and carbon cycle
No abstract available.
Authors
John Crusius, J.L. Nielsen
Submarine groundwater discharge to a small estuary estimated from radon and salinity measurements and a box model Submarine groundwater discharge to a small estuary estimated from radon and salinity measurements and a box model
Submarine groundwater discharge was quantified by a variety of methods for a 4-day period during the early summer of 2004, in Salt Pond, adjacent to Nauset Marsh, on Cape Cod, USA. Discharge estimates based on radon and salinity took advantage of the presence of the narrow channel connecting Salt Pond to Nauset Marsh, which allowed constructing whole-pond mass balances as water flowed in...
Authors
John Crusius, D. Koopmans, John F. Bratton, M.A. Charette, K.D. Kroeger, P. Henderson, L. Ryckman, K. Halloran, John A. Colman
A preliminary evaluation of nutrient and ground-water fluxes to the Neuse River Estuary, North Carolina A preliminary evaluation of nutrient and ground-water fluxes to the Neuse River Estuary, North Carolina
No abstract available.
Authors
Timothy B. Spruill, John F. Bratton, John Crusius, Beth M. Wrege, G. Strickland
Submarine ground-water discharge and its role in coastal processes and ecosystems Submarine ground-water discharge and its role in coastal processes and ecosystems
Submarine ground-water discharge (SGD) has recently been recognized as a phenomenon that can strongly influence coastal water and geochemical budgets and drive ecosystem change. For example, the discharge of nutrient-enriched ground water into coastal waters may contribute significantly to eutrophication and blooms of harmful algae. Similarly, the quantity of SGD can also directly affect...
Authors
Peter W. Swarzenski, John F. Bratton, John Crusius
Export production in the subarctic North Pacific over the last 800 kyrs: No evidence for iron fertilization? Export production in the subarctic North Pacific over the last 800 kyrs: No evidence for iron fertilization?
The subarctic North Pacific is a high nitrate-low chlorophyll (HNLC) region, where phytoplankton growth rates, especially those of diatoms, are enhanced when micronutrient Fe is added. Accordingly, it has been suggested that glacial Fe-laden dust might have increased primary production in this region. This paper reviews published palaeoceanographic records of export production over the...
Authors
S.S. Kienast, I.L. Hendy, John Crusius, Thomas F. Pedersen, S.E. Calvert
Influence of natural organic matter source on copper speciation as demonstrated by Cu binding to fish gills, by ion selective electrode, and by DGT gel sampler Influence of natural organic matter source on copper speciation as demonstrated by Cu binding to fish gills, by ion selective electrode, and by DGT gel sampler
Rainbow trout (Oncorhynchus mykiss, 2 g) were exposed to 0−5 μM total copper in ion-poor water for 3 h in the presence or absence of 10 mg C/L of qualitatively different natural organic matter (NOM) derived from water spanning a large gradient in hydrologic residence time. Accumulation of Cu by trout gills was compared to Cu speciation determined by ion selective electrode (ISE) and by...
Authors
C.D. Luider, John Crusius, R.C. Playle, P.J. Curtis
Influence of northwest Pacific productivity on North Pacific Intermediate Water oxygen concentrations during the Bølling-Ållerød interval (14.7-12.9 ka) Influence of northwest Pacific productivity on North Pacific Intermediate Water oxygen concentrations during the Bølling-Ållerød interval (14.7-12.9 ka)
Elevated productivity in the northwest Pacific is suggested as a new possible control driving past intervals of low-O2 intermediate water along the western continental margin of North America. According to this mechanism, O2 consumption would occur near the site of formation of North Pacific Intermediate Water (NPIW), due to increased respiration of organic carbon in response to a high
Authors
John Crusius, Thomas F. Pedersen, Stephanie Kienast, Lloyd D. Keigwin, Laurent Labeyrie
Bioturbation depths, rates and processes in Massachusetts Bay sediments inferred from modeling of 210Pb and 239 + 240Pu profiles Bioturbation depths, rates and processes in Massachusetts Bay sediments inferred from modeling of 210Pb and 239 + 240Pu profiles
Profiles of 210Pb and 239 + 15 cm depth or that biodiffusive mixing mediated by other organisms is occurring at depth. Additional constraints from surficial sediment 234Th data suggest that in this half of the cores, the vast majority of the present-day flux of recent, nuclide-bearing material to these core sites is transported over a timescale of a month or more to a depth of a few...
Authors
John Crusius, Michael H. Bothner, Christopher K. Sommerfield
Science and Products
Filter Total Items: 40
Continuous resistivity profiling data from the upper Neuse River Estuary, North Carolina, 2004-2005 Continuous resistivity profiling data from the upper Neuse River Estuary, North Carolina, 2004-2005
The Neuse River Estuary in North Carolina has suffered impacts of eutrophication in recent years. As part of a larger project to better constrain nutrient budgets in the estuary, field investigations were performed to study occurrence and discharge of fresh and brackish ground water and nutrients beneath the estuary itself (fig. 1). A Continuous Resistivity Profiling (CRP) system...
Authors
VeeAnn A. Cross, John F. Bratton, Emile M. Bergeron, Jeff K. Meunier, John Crusius, Dirk Koopmans
Submarine ground-water discharge: nutrient loading and nitrogen transformations Submarine ground-water discharge: nutrient loading and nitrogen transformations
Eutrophication of coastal waters due to nonpoint source land-derived nitrogen (N) loads is a worldwide phenomenon and perhaps the greatest agent of change altering coastal ecology (National Research Council, 2000; Howarth and others, 2000). Within the United States, a majority of estuaries have been determined to be moderately to severely impaired by eutrophication associated with...
Authors
Kevin D. Kroeger, Peter W. Swarzenski, John Crusius, John F. Bratton, Matthew A. Charette
Processes influencing the transport and fate of contaminated sediments in the coastal ocean — Boston Harbor and Massachusetts Bay Processes influencing the transport and fate of contaminated sediments in the coastal ocean — Boston Harbor and Massachusetts Bay
No abstract available.
Authors
P. Soupy Alexander, Dann S. Blackwood, Jonathan Borden, Michael A. Casso, John Crusius, Joanne Goudreau, Linda H. Kalnejais, Paul J. Lamothe, William R. Martin, Marinna A. Martini, Sandra M. Milbert, Richard R. Rendigs, Frederick L. Sayles, Richard P. Signell, Page C. Valentine, John C. Warner
Putting radon to work: identifying coastal ground-water discharge sites Putting radon to work: identifying coastal ground-water discharge sites
No abstract available.
Authors
John Crusius, John F. Bratton, Matt Charette
Coastal iron fluxes to surface waters of the NE Pacific: A driver of the marine ecosystem and carbon cycle Coastal iron fluxes to surface waters of the NE Pacific: A driver of the marine ecosystem and carbon cycle
No abstract available.
Authors
John Crusius, J.L. Nielsen
Submarine groundwater discharge to a small estuary estimated from radon and salinity measurements and a box model Submarine groundwater discharge to a small estuary estimated from radon and salinity measurements and a box model
Submarine groundwater discharge was quantified by a variety of methods for a 4-day period during the early summer of 2004, in Salt Pond, adjacent to Nauset Marsh, on Cape Cod, USA. Discharge estimates based on radon and salinity took advantage of the presence of the narrow channel connecting Salt Pond to Nauset Marsh, which allowed constructing whole-pond mass balances as water flowed in...
Authors
John Crusius, D. Koopmans, John F. Bratton, M.A. Charette, K.D. Kroeger, P. Henderson, L. Ryckman, K. Halloran, John A. Colman
A preliminary evaluation of nutrient and ground-water fluxes to the Neuse River Estuary, North Carolina A preliminary evaluation of nutrient and ground-water fluxes to the Neuse River Estuary, North Carolina
No abstract available.
Authors
Timothy B. Spruill, John F. Bratton, John Crusius, Beth M. Wrege, G. Strickland
Submarine ground-water discharge and its role in coastal processes and ecosystems Submarine ground-water discharge and its role in coastal processes and ecosystems
Submarine ground-water discharge (SGD) has recently been recognized as a phenomenon that can strongly influence coastal water and geochemical budgets and drive ecosystem change. For example, the discharge of nutrient-enriched ground water into coastal waters may contribute significantly to eutrophication and blooms of harmful algae. Similarly, the quantity of SGD can also directly affect...
Authors
Peter W. Swarzenski, John F. Bratton, John Crusius
Export production in the subarctic North Pacific over the last 800 kyrs: No evidence for iron fertilization? Export production in the subarctic North Pacific over the last 800 kyrs: No evidence for iron fertilization?
The subarctic North Pacific is a high nitrate-low chlorophyll (HNLC) region, where phytoplankton growth rates, especially those of diatoms, are enhanced when micronutrient Fe is added. Accordingly, it has been suggested that glacial Fe-laden dust might have increased primary production in this region. This paper reviews published palaeoceanographic records of export production over the...
Authors
S.S. Kienast, I.L. Hendy, John Crusius, Thomas F. Pedersen, S.E. Calvert
Influence of natural organic matter source on copper speciation as demonstrated by Cu binding to fish gills, by ion selective electrode, and by DGT gel sampler Influence of natural organic matter source on copper speciation as demonstrated by Cu binding to fish gills, by ion selective electrode, and by DGT gel sampler
Rainbow trout (Oncorhynchus mykiss, 2 g) were exposed to 0−5 μM total copper in ion-poor water for 3 h in the presence or absence of 10 mg C/L of qualitatively different natural organic matter (NOM) derived from water spanning a large gradient in hydrologic residence time. Accumulation of Cu by trout gills was compared to Cu speciation determined by ion selective electrode (ISE) and by...
Authors
C.D. Luider, John Crusius, R.C. Playle, P.J. Curtis
Influence of northwest Pacific productivity on North Pacific Intermediate Water oxygen concentrations during the Bølling-Ållerød interval (14.7-12.9 ka) Influence of northwest Pacific productivity on North Pacific Intermediate Water oxygen concentrations during the Bølling-Ållerød interval (14.7-12.9 ka)
Elevated productivity in the northwest Pacific is suggested as a new possible control driving past intervals of low-O2 intermediate water along the western continental margin of North America. According to this mechanism, O2 consumption would occur near the site of formation of North Pacific Intermediate Water (NPIW), due to increased respiration of organic carbon in response to a high
Authors
John Crusius, Thomas F. Pedersen, Stephanie Kienast, Lloyd D. Keigwin, Laurent Labeyrie
Bioturbation depths, rates and processes in Massachusetts Bay sediments inferred from modeling of 210Pb and 239 + 240Pu profiles Bioturbation depths, rates and processes in Massachusetts Bay sediments inferred from modeling of 210Pb and 239 + 240Pu profiles
Profiles of 210Pb and 239 + 15 cm depth or that biodiffusive mixing mediated by other organisms is occurring at depth. Additional constraints from surficial sediment 234Th data suggest that in this half of the cores, the vast majority of the present-day flux of recent, nuclide-bearing material to these core sites is transported over a timescale of a month or more to a depth of a few...
Authors
John Crusius, Michael H. Bothner, Christopher K. Sommerfield