Axenic cultures of 25 species of unicellular marine algae were tested for their ability to utilize nine common amino acids, supplied at high concentrations in batch culture, as a nitrogen source; most species were able to use several amino acids, although growth was often slower than on nitrate nitrogen. The...
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...
Using 15N-labeled NH4+, we assessed the time-course of NH4+ uptake, the parameters of saturation kinetics, and the rates of incorporation of NH4+ into trichloroacetic acid-insoluble material by Chesapeake Bay phytoplankton. The amount of NH4+ taken up by the phytoplankton increased linearly with time for 2 h for all samples growing...
Ammonium uptake and regeneration rates were measured in time course experiments with 15N as a tracer. Both ammonium uptake and regeneration rates measured over 12 to 18 h remained essentially constant. However, as the length of the incubations increased the amount of usable data decreased dramatically due to substrate depletion...
The stable isotopic signature of dissolved inorganic carbon (δ¹³CDIC) in the northeast Pacific Ocean is lower in near-surface waters by 1.1‰ relative to values predicted from global oceanic trends of δ¹³CDIC versus nutrients. A combination of anthropogenic carbon uptake from the atmosphere and thermodynamic, air-sea gas exchange processes in different...
The relationship between nitrogen (N) availability and the growth of macroalgae in a seasonal upwelling region (Yaquina Head, Oregon, USA) was investigated. Water column nutrient concentrations were relatively high and stable during the winter, decreased in early spring, and were highly variable in the summer and early fall. Periods of...
Insight into the dependence of benthic communities on biological and physical processes in nearshore pelagic environments, long considered a ``black box,'' has eluded ecologists. In rocky intertidal communities at Oregon coastal sites 80 km apart, differences in abundance of sessile invertebrates, herbivores, carnivores, and macrophytes in the low zone were...
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...
Chlorophyll a concentrations were measured as a function of depth from 28 to 48°N along 152°W in March 1991 with Whatman GF/F and 0.2‐µm Nuclepore filters. Surface Chl a concentrations measured with 0.2‐µm Nuclepore filters were up to fourfold higher than those measured with Whatman GF/F filters. The largest difference...
Observed changes in the nutrient levels in the halocline of the California Current during 2002 indicated a natural eutrophication that was accompanied by increased chlorophyll and oxygen in surface water. Decreased oxygen in the lower water column over the shelf indicated that much of the phytoplankton production was respired rather...
Analyzes subscription costs and impact factors for journals in which COAS faculty most frequently published from 1994-2003. Includes a spreadsheet with journal title, subscription cost, impact factor, publisher, information about whether the journal is published by a non-profit or commercial publisher, and cost per page.
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....
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....
The Coastal Ocean Advances in Shelf Transport (COAST) program conducted an
interdisciplinary study of coastal upwelling off central Oregon during summer 2001.
Two intensive field efforts during May–June and August 2001 were coordinated with
ocean circulation, ecosystem, and atmospheric modeling of the region. A primary
goal was to contrast the...
The relationship between iron and nitrate concentrations was examined off the coast of
Oregon during the upwelling season. Surface Fe and N (nitrate + nitrite) concentrations
measured underway by flow injection analysis ranged from <0.3 to 20 nmol L¯¹ and <0.1 to
30 mmol L¯¹, respectively. Total dissolvable Fe concentrations,...
Despite the importance of the spring phytoplankton bloom off Oregon as a food source for zooplankton, little is known about the sources of phytoplankton seed stock for the bloom or its timing. Experiments were conducted in the late winter to determine if the benthic boundary layer (BBL) could be a...
The uptake of methylammonium (MA) by Chesapeake Bay phytoplankton was measured in short term experiments by using the 14C radioisotope. This uptake was inversely related to ambient NH4+ concentrations, and the specificity for uptake of both substrates was demonstrated by competitive inhibition. At stations with low ambient NH4+, MA uptake...
PN-specific, absolute, and Chl a-specific nitrate uptake rates were measured during two upwelling seasons and one winter off Oregon. Although PN-specific and absolute uptake rates showed no dependence on nitrate concentration, Michaelis-Menten kinetics applied when the uptake rates were normalized to Chl a. Chl a-specific nitrate uptake rates were saturated...
The uptake rates of nitrate, ammonium, and urea were measured with a ¹⁵N technique during seven cruises in the marginal ice zone (MIZ) in the Barents Sea in 1984–1988. The results from all the cruises were pooled to obtain means for the prebloom, bloom, transition, and postbloom periods. New production—nitrate...
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...
We examined high-resolution cross-shelf distributions of particulate organic carbon
(POC) and dissolved O₂ during the upwelling season off the Oregon coast. Oxygen
concentrations were supersaturated in surface waters, and hypoxic in near-bottom
waters, with greatly expanded hypoxic conditions late in the season. Simplified time-dependent
mass balances on cross-shelf integrated concentrations...
The particulate and dissolved organic carbon and nitrogen data included in this report are
a complete version of all data for GLOBEC cruises 1997-2004. The nutrient and
chlorophyll data that correspond to this data set can be found in “Nutrient and Extracted
Chlorophyll Data from the GLOBEC Long-Term Observation Program,...
The particulate and dissolved organic carbon and nitrogen data included in this report are a complete version of all data for GLOBEC cruises 1997-2004. The nutrient and chlorophyll data that correspond to this data set can be found in "Nutrient and Extracted Chlorophyll Data from the GLOBEC Long-Term Observation Program,...
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 5 lines (off Newport, Heceta Head, Coos Bay, the Rogue River, OR. and Crescent
City, CA.), to make continuous...
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 4 lines (off Newport, Heceta Head, Coos Bay, OR. and Crescent City, CA.), to
deploy drifters at selected locations...
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 one line off Newport, OR, and to make continuous observations of currents using
ADCP and of surface-layer temperature, salinity...
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 5 lines (off Newport, Heceta Head, Coos Bay, the Rogue River and Crescent City, OR, to deploy drifters at...
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 5 lines (off Newport, Heceta Head, Coos Bay, the Rogue River, OR. and Crescent
City, CA., to make continuous...
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 5 lines (off Newport, Heceta Head, Coos Bay, the Rogue River, OR. and Crescent
City, CA.), to make continuous...
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...
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 5 lines (off Newport, Heceta Head, Coos Bay, the Rogue River, OR. and Crescent
City, CA.), to make continuous...
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...
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 5 lines (off Newport, Heceta Head, Coos Bay, the Rogue River, OR. and Crescent
City, CA.), to make continuous...
PURPOSE: To determine physical, plankton and nutrient/chemical conditions over the continental
margin for climate change studies in the NE Pacific. In particular, to make 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 currents...
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...
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 5 lines (off Newport, Heceta Head, Coos Bay, the Rogue River, OR. and Crescent
City, CA.), to make continuous...
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 5 lines (off Newport, Heceta Head, Coos Bay, the Rogue River, OR. and Crescent
City, CA.), to make continuous...
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, and to make continuous observations of currents using
ADCP and of surface-layer temperature, salinity and...
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, and to make continuous observations of currents using
ADCP and of surface-layer temperature, salinity and...
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 5 lines (off Newport, Heceta Head, Coos Bay, the Rogue River, OR. and Crescent
City, CA.), to deploy drifters...
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 5 lines (off Newport, Heceta Head, Coos Bay, OR. and Crescent City, CA.), to
deploy drifters at selected locations...
PURPOSE (W0408D): 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 3 lines (off Newport, Strawberry Hill and Heceta Head, OR.), and
to make continuous observations of currents...
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 4 lines (off Newport, Coos Bay, Crescent City and Eureka), to make additional
stations along a fifth line (off...
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 one lines off Newport, OR, and to make continuous observations of currents using ADCP and of surface-layer temperature, salinity...
Few studies have examined the partitioning of organic matter in upwelling systems, despite the fact that these systems play a key role in carbon and nitrogen budgets in the ocean. We examined the production and partitioning of phytoplankton-derived organic matter in deck incubations off Oregon during the upwelling season. During...
The data set presented here includes the discrete depth profile data and time series data
from the vertical profiling cruises carried out as a portion of the “Coastal Ocean Advances in Shelf Transport” (COAST) project. The primary purpose for collection of this data set was to calibrate the optical parameters...
Dissolved organic matter (DOM) production was examined in axenic batch cultures of five coastal diatom species. For Chaetoceros decipiens, dissolved organic carbon (DOC) accumulated beginning in late exponential growth as a result of increased cell density. For Cylindrotheca closterium, DOC actually decreased in late exponential growth and reached zero by...
Until recently, studies of the fate of primary production in coastal upwelling systems have focused mainly on export through sinking of particulate organic matter (POM). In week-long deck incubations conducted during the upwelling season off Oregon, a large accumulation of carbonrich (C:N ≥ 16) dissolved organic matter (DOM) occurred following...
Three cross‐shelf transects were conducted off northern Oregon in February, 2003, coincident with flooding of Coast Range rivers, to assess the riverine impact on coastal ocean biogeochemistry. During downwelling conditions, low salinity river‐influenced water was located in a narrow band near the coast and contained elevated macronutrient, iron, and organic...
On Oregon coastal rocky shores, filter‐feeders were relatively abundant and macrophytes were relatively scarce at Strawberry Hill, whereas opposite abundance patterns occurred at Boiler Bay. To determine whether nearshore oceanographic differences were associated with these patterns, we made shore‐based measurements of nutrient and Chl a concentrations. We used a three‐level...
Reports the work of the 2004/2005 Oregon State University Faculty Senate Task Force on Scholarly Communication. Report: Determines the current practices that impede an open and sustainable system of scholarly communication, citing data where necessary to substantiate the findings;
2. Determines actions that OSU faculty members, as authors, readers, reviewers,...
This project, part of the Northeast Pacific GLOBEC Long Term Observation Project (NEPGLOBEC-
LTOP), constitutes the first multi-year study of phytoplankton variability in the Oregon coastal
environment. The work divides into two studies: analysis of interseasonal change and analysis of detailed
changes within the summer upwelling period. In the first...
Dissolved C, N, P, and Si budgets for Tomales Bay, California, have been used to solve simultaneous stoichiometric equations which describe a plausible material balance for net organic matter reactions in the bay. Dissolved Si and P were both exported hydrographically. Dissolved C and fixed N were imported hydrographically. If...
This report is the eighth in a series that describe recent oceanographic observations within the California Current system, from Oregon to Baja California. The emphasis here is placed on the observations conducted concurrently by the CalCOFI (California Cooperative Oceanic Fisheries Investigations), IMECOCAL (Investigaciones Mexicanas de la COrriente de CALifornia), and...
This report summarizes physical and biological conditions in the California Current System (CCS), from Oregon to Baja California, in 2001 and 2002. The principal sources of the observations described here are the CalCOFI (California Cooperative Oceanic Fisheries Investigations), IMECOCAL (Investigaciones Mexicanas de la Corriente de California), and U.S. GLOBECLTOP (Global...
This report describes the state of the California Current System (CCS)—meteorological, physical, chemical, and biological—from January 2003 to the spring of 2004. The area covered in this report ranges from Oregon coastal waters to southern Baja California. Over the past year, most physical, chemical, and biological parameters were close to...
This report summarizes the recent state of the California Current System (CCS), primarily during the period of April 2004 to January 2005. The report is based on observations made between Oregon and Baja California by various ocean observing programs. The CCS was not forced by any coherent basin-wide processes during...
A pair of hydrographic sections, one north and one south of Cape Blanco at 42.9N, was sampled in five summers (1998–2000 and 2002–2003). The NH line at 44.6N lies about 130 km south of the Columbia River, and spans a relatively wide shelf off Newport, Oregon. The CR line at...
As part of the U. S. GLOBEC NorthEast Pacific
Program we made repeated seasonal hydrographic surveys in
the northern California Current system between July
1997 and September 2003. These surveys included sampling
along a pair of hydrographic sections, one north (at 44.6ºN)
and one south (at 41.9ºN) of Cape Blanco...
As part of the U. S. GLOBEC NorthEast Pacific Program we made repeated seasonal hydrographic surveys in the northern California Current system (Figure 1) between July 1997 and September 2003. These surveys included early spring sampling along a pair of hydrographic sections, one north (at 44.6ºN) and one south (at...
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...
Uptake of [14C]glycine by various size fractions of natural plankton communities was measured to determine if phytoplankton can compete effectively with other members of the plankton community for the free amino acids in seawater. The simultaneous occurrence of glycine uptake, plant pigments, and photosynthetic activity in the same size fractions,...
The second in a series of articles published in OSU This Week by members of the Faculty Senate Library Committee regarding threats to an open and sustainable system of scholarly communication and potential solutions. Article describes what journal impact factors are and how they are determined and makes recommendations for...
The relative contribution of various inorganic and organic forms of nitrogen to the nitrogen requirements of picoplankton was examined with 15N tracers. Size fractionation was used to measure uptake by <1-μM size microorganisms, and inhibitors of protein synthesis were used to separate procaryotic from eucaryotic nitrogen uptake, Picoplankton utilized mainly...
This project, part of the Northeast Pacific GLOBEC Long Term Observation Project (NEPGLOBEC-
LTOP), constitutes the first multi-year study of phytoplankton variability in the Oregon coastal
environment. The work divides into two studies: analysis of interseasonal change and analysis of detailed
changes within the summer upwelling period. In the first...
This project, part of the Northeast Pacific GLOBEC Long Term Observation Project (NEPGLOBEC-
LTOP), constitutes the first multi-year study of phytoplankton variability in the Oregon coastal
environment. The work divides into two studies: analysis of interseasonal change and analysis of detailed
changes within the summer upwelling period. In the first...