A cruise of the R/V Yaquina off Oregon during June and July of
1968 provided data for a study of the relationships of hydrographic
and chemical parameters to estimates of biological activity. The
emphasis was on carbon and nitrogen reservoirs. Phytoplankton pigments,
nitrogen and C/N ratio were used along with...
A method for measuring food carbon assimilation in the copepod
Calanus finmarchicus was developed, using the diatom Ditylum
brightwelli as food. The amount of particulate food carbon ingested
was determined as the difference between CHN analyzer analyses for
particulate food carbon of pre- and post-grazed food suspensions.
The fraction of...
A simplified autoradiographic method for estimating species-specific
phytoplankton production rates in mixed natural communities
was evaluated in the laboratory and employed in the field. Laboratory
experiments were designed to test the reliability and variability of
the simplified method. Assays of ¹⁴C uptake by liquid scintillation
spectrometry were used to evaluate...
Large-volume (20-liter) bioassays were carried out in order to
assess the effects of major nutrients and micro-nutrients on
natural phytoplankton populations in water collected from a site
close to the mouth of Yaquina Bay, Oregon. Seven long-term
experiments were conducted during the years 1975-1976. A stripping
technique employing activated carbon...
A chemostatic system was developed for the long term studies
of population dynamics of chain forming diatoms. Vessel volume
rather than flow rate was varied in these systems to obtain different
growth rates at steady state in systems with an equal capacity to
produce.
Population level responses to high dilution...
Short-term changes in the distribution, surface to 10 meters, of
phytoplankton-associated trace metals (Fe, Mn, Cr, Zn, Co, Ni, and
Cu) were studied in the near-shore waters off Humboldt Bay,
California, through the summer of 1971. The depth distribution of
phytoplankton-associated trace metals was related to local hydrography.
During periods...
Global increases in ultraviolet-B radiation (UVBR:290-
320 nm) resulting from decreases in stratospheric ozone
concentration have the potential to alter marine primary
production and affect global climate and marine trophic
dynamics. Effects of UVBR on phytoplankton carbon fixation
were determined from open ocean exposure studies conducted
off the coast of...
The Columbia River Estuary was sampled during high (May-June), intermediate (July), and low (September-October) river flow seasons to further define the role of the ETM with respect to its effect on primary biomass and production, and to discover how this effect changes in space and time.
Strong ETMs were determined...
