Index Catalog // ScholarsArchive@OSU

Creator:: Wheeler, Patricia A. and Kokkinakis, Steven A.
Abstract:: Seasonal and diel changes in nutrient concentrations and nitrogen assimilation rates were used to assess the effects of NH4+ on NO3- assimilation. Surface-water NO3- concentrations ranged from 6 to 17 μM while NH4+ concentrations ranged from 0 to 0.4 μM. Total N assimilation ranged from 84 to 732 nM d–1...
Resource Type:: Article

Creator:: Kirchman, David L., Keil, Richard G., and Wheeler, Patricia A.
Abstract:: The purpose of this study was to test the hypothesis that NH4+ uptake by heterotrophic bacteria in the subarctic Pacific is C limited. Addition of glucose (0.5–1.0 μM) stimulated NH4+ uptake in unfractionated water but had no effect on bacterial abundance. Glucose stimulation of NH4+ uptake was even greater in...
Resource Type:: Article

Creator:: Wheeler, Patricia A., Kirchman, David L., Landry, Michael R., and Kokkinakis, Steven A.
Abstract:: Diel periodicity in NH4+ uptake and regeneration in the nutrient-rich environment of the oceanic subarctic Pacific was examined. Surface water was incubated in large shipboard microcosms that allowed repeated sampling of the planktonic community for NH4+ cycling rates, bacterial production rates, and population densities of the dominant autotrophs and heterotrophs....
Resource Type:: Article

Creator:: Miller, Charles B., Frost, Bruce W., Wheeler, Patricia A., Landry, Michael R., Welschmeyer, Nicholas, and Powell, Thomas M.
Abstract:: It has been suggested that production in offshore waters of the subarctic Pacific is limited by availability of dissolved Fe. Although that is not yet adequately established, the functional consequences of the limitation (if it exists) can be characterized from the results of the Subarctic Pacific Ecosystem Research (SUPER) program....
Resource Type:: Article

Creator:: Kokkinakis, Steven A. and Wheeler, Patricia A.
Abstract:: Uptake of nitrogenous nutrients by microplankton off the Washington and Oregon coasts was measured during the 1985 upwelling period. Nitrogen uptake rates in low-NO3- waters (<5 μM) were 0.020–0.258 μmol N liter-1 h-1 and were primarily supported by regenerated nitrogen (71% of total uptake). Nitrogen uptake rates in high-NO3- waters...
Resource Type:: Article

Creator:: Fleischbein, Jane, Huyer, Adriana, 1945-, Smith, Robert L. (Robert Lloyd), 1935-, Kosro, P. Michael, 1951-, Wheeler, Patricia A., Peterson, W. T., Barth, Jack A., Sherr, Barry F., and Sherr, Evelyn
Abstract:: PURPOSE: To determine physical, plankton and nutrient/chemical conditions over the continental margin for climate change studies in NE Pacific. In particular, to make CTD and CTD/rosette and net tow stations along the Newport Hydro line, to make continuous bio-acoustic observations between the 50-500m. isobath, and to make continuous observations of...
Resource Type:: Technical Report

Creator:: Kokkinakis, Steven A. and Wheeler, Patricia A.
Abstract:: The stable isotope 15N was used to measure nitrogen uptake in the coastal upwelling region off Oregon and Washington, USA, where nitrate concentrations in the surface water ranged from 0.7 to 49.1 μM. Nanoplankton biomass (1 to 10 pm) was relatively more abundant at low-nitrate stations, while netplankton biomass (10...
Resource Type:: Article

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