Browse by Archive
ScholarsArchive at Oregon State University
|
During Leg 168 of the Ocean Drilling Program, basalts were recovered by drilling and subsurface water was collected with
a water sampling tool at Hole 1026B on the east flank of Juan de Fuca Ridge. Microorganisms were found in both types of...
2000 (iso8601)
|
|
The pentacyclic tritcrpene
17β(H), 21β(H)-hop-22(29)-ene (diploptence) occurs
in sediments throughout the Columbia River
drainage basin and off the southern coast of
Washington state in concentrations comparable
to long-chain plantwax n-alkanes....
1992 (iso8601)
|
|
Detailed upper ocean profiles of 234Th in dissolved (< 10,000 Daltons), colloidal (10,000 Da–O.45 μm),
and particulate (>0.45 μm) forms were measured at a station (46º45′N, 126ºW) in the northeast Pacific
Ocean. On average, dissolved, colloidal,...
1995 (iso8601)
|
|
This study examines the impact of two decades of neoliberal policy
reform on food production and household livelihood security in
three West African countries. The rice sectors in The Gambia, Côte
d’Ivoire, and Mali are scrutinized as well as...
2010 (iso8601)
|
|
Benthic chamber measurements of the reactants and products involved with biogenic matter diagenesis (oxygen, ammonium, nitrate, silicate, phosphate, TCO₂, alkalinity) were used to define
fluxes of these solutes into and out of the sediments off...
1996-07-01 (iso8601)
|
|
We present a decade-long (1981–1990) high-resolution (subseasonal) record of Pb and Cd
concentrations and Pb isotopic composition in a series of 119 snow samples from a 6-m snow pit at
Summit, Greenland. Both metals show order of magnitude...
2000-05-30 (iso8601)
|
|
During SHEBA, thin ice and freshening of the Arctic Ocean surface in the Beafort Sea led to speculation that perennial sea ice was disappearing [McPhee et al., 1998]. Since 1987, we have collected salinity, δ¹⁸O and Ba profiles near the initial...
1999-08-01 (iso8601)
|
|
We model the response o f the climate system during Heinrich event 2 (H2) by employing an atmospheric general circulation model, using boundary conditions based on the concept of a "canonical" Heinrich event. The canonical event is initialized...
1999-02-27 (iso8601)
|
|
Many ocean regions important to the global carbon budget, including the equatorial Pacific Ocean, have low chlorophyll concentrations despite high levels of conventional nutrients. Iron may instead by the limiting nutrient, and elevated input of...
1995-12 (iso8601)
|
|
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...
2000-09 (iso8601)
|
|
Carbon isotopically based estimates of CO₂ levels have been generated from a record of the photosynthetic fractionation of ¹³C (≡εp) in a central equatorial Pacific sediment core that spans the last ~255 ka. Contents of ¹³C in phytoplanktonic...
1994-12 (iso8601)
|
|
We examine the utility of the uranium (U) content of planktonic foraminifera tests as an indicator of past changes in seawater U content. The U/Ca ratio in foraminifera from Atlantic and Caribbean cores in constant in the Holocene and decreases by...
1996-12 (iso8601)
|
|
Multiproxy geologic records of δ18O and Mg/Ca in fossil foraminifera from sediments under the Eastern Pacific Warm Pool (EPWP) region west of Central America document variations in upper ocean temperature, pycnocline strength, and salinity (i.e.,...
2006-08 (iso8601)
|
|
Pacific winter waters, a major source of nutrients and buoyancy to the Arctic Ocean, are thought to ventilate the Arctic's lower halocline either by injection (isopycnal or penetrative) of cold saline shelf waters, or by cooling and freshening...
2005-09-29 (iso8601)
|
|
Distributions of temperature, salinity, and barium in near-surface waters (depth ≤ 50 m) of the Laptev Sea and adjacent areas of the Arctic Ocean are presented for the summers of 1993, 1995, and 1996. The tracer data indicate that while fluvial...
2001-06-15 (iso8601)
|
|
Dissolved barium (Ba) was measured along transects across Fram and Denmark
Straits as part of the 1998 ARK-XIV/2 Polarstern expedition. Results are combined
with other available tracer observations to analyze water mass composition at Fram Strait....
2003-12-05 (iso8601)
|
|
In the Arctic Ocean, Pacific source water can be distinguished from Atlantic source
water by nitrate-phosphate concentration relationships, with Pacific water having higher
phosphate concentrations relative to those of nitrate. Furthermore,...
2003-04-12 (iso8601)
|
|
Female calanoid copepods of the family Calanidae can mature with either the juvenile and most typical female pattern of setation, termed trithek (T), or with the male pattern, termed quadrithek (Q). It was suggested by Fleminger (1985), but not...
2005-10-11 (iso8601)
|
|
Phytoplankton biomass in high-nitrate, low-chlorophyll (HNLC) ocean regions exhibits a pronounced stability: variation occurs only within a narrow range of values. The magnitude of this variation has profound ecological and geochemical...
2000-02-28 (iso8601)
|
|
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...
2002-07-31 (iso8601)
|
|
Degradation and release to solution of intracellular dimethylsulfoniopropionate (DMSP) from Emiliania huxleyi 370 was observed during grazing by the heterotrophic dinoflagellate Oxyrrhis marina in 24 h bottle incubations. Between 30 and 70 % of...
1994-08-11 (iso8601)
|
|
The concentrations of filamentous diazotroph Trichodesmium spp., present as free trichomes and in colonial assemblages, were measured at approximately monthly intervals at Stn ALOHA (22°45'N, 158°00'W) between October 1989 and December 1992. The...
1996-03-28 (iso8601)
|
|
In order to understand what controls the composition of suspended particulate material (SPM) in estuarine turbidity maxima (ETM), a set of SPM samples collected in the Columbia River and estuary (northwestern USA) during 3 seasons (fall 1990,...
1997-12-15 (iso8601)
|
|
The decomposition of marine plankton in two-chamber, seawater-filled microbial fuel cells (MFCs) has been
investigated and related to resulting chemical changes, electrode potentials, current efficiencies, and microbial
diversity. Six experiments...
2007-11 (iso8601)
|
|
Sequences of coastal zone color scanner (CZCS) images from the offshore region adjacent to Vancouver Island, Canada, have been analyzed to estimate the time rate of decorrelation of surface phytoplankton chlorophyll pigment patterns. In these...
1988-06-15 (iso8601)
|
