Thesis (Ph. D.)--University of Texas at Austin, 2005. / Supervisor: Edward J. Buskey. Vita. Includes bibliographical references.

Thesis (M.S.)--University of Delaware, 2007. / Principal faculty advisor: Karl E. Wommack, Dept. of Plant & Soil Sciences. Includes bibliographical references.

Thesis (M.S.)--Baylor University, 2006. / Includes bibliographical references (p. 62-67).

The major constituents of the plankton, phytoplankton, cladocera, copepods and chaetognaths, sampled in the 1951 oceanographic survey of the British Columbia Inlets are reported in concentrations per cubic meter of water. Horizontal plankton tows sampled four depths, 5, 21, 32 and 47 feet, respectively. The distribution of each group is discussed in relation to the hydrographic data and the present theory of inlet circulation. The inlets investigated fall into two general groups, (a) those which are long and have a large freshwater discharge at the head and (b) those which have a small freshwater discharge and are short. The data from six inlets making up the former have been grouped together and are discussed as the Average Inlet. Those inlets making up the latter group are classified under the general heading of atypical inlets; each is discussed separately. In the Average Inlet the plankton volumes were the greatest at the mouth, particularly towards the surface. The concentration of plankton is shown to be a result of local phytoplankton production. In the absence of currents the phytoplankton are shown to be limited vertically by density. The zooplankton are divided into three groups on the basis of their response to the physical factors. The distribution of cladocera indicates that it is positively phototropic while that of the copepods and chaetognaths indicate that that they are negatively phototropic. The chaetognaths are found to be absent from all the atypical inlets, the cladocera from three. The copepods are concentrated at the depth which is associated with the compensation light intensity. Attention is drawn to the fact that this report is a qualitative description of the relationship between the distribution of the plankton and the physical oceanographic conditions. Future surveys will have to sample more extensively and intensively. / Science, Faculty of / Zoology, Department of / Graduate

The northern Strait of Georgia (NSG) and adjacent Malaspina Complex of inlets (MC) were studied to determine the effect of stratification on microplankton communities. The NSG was dominated by nanoflagellates in spring. There was no evidence of a vernal diatom bloom in the Strait, perhaps due to wind turbulence or microzooplankton grazing. In early summer regimes were conducive to diatom growth but the northern Strait was experiencing a "mild" red tide. By late summer, diatoms bloomed and prevailed, presumably, till the fall decline. Stratification was greatest in late summer, due chiefly to temperature, with reduced surface salinities on the east side from Fraser River runoff. At this time biological partitioning was pronounced, resulting in a mosaic of organismal groups. Although stratification had declined by early autumn, the mosaicism was maintained and strengthened. Diatoms were most abundant in the north and on the west side where stratification was least, in areas of tidal turbulence. Photosynthetic nanoflagellates and photosynthetic dinoflagellates favoured the more stratified east side. Ciliate distributions mirrored those of the nanoflagellates. The MC was thought to be a more stratified version of the NSG but it was found to be a fairly mixed water body due to tidal action. It was sheltered from winds which allowed the early blooming of diatoms. These were maintained for several months by a tidal jet through Malaspina Inlet that probably injected nutrients into the junction of Malaspina, Okeover, and Lancelot Inlets. Principal components analysis was used to reduce the dimensionality of the biological dataset, and canonical correlation analysis allowed the coupling of environmental data to the biological principal components. It was found that PCI reflected general biomass while PC's II and III were most often related to depth and location. These latter two were utilised to resolve the species information in three-dimensions. In general, nanoflagellates populated surface waters whereas diatoms tended to occupy deeper depths. Multiple regression analysis was performed on organismal groups to explore how biomass was affected by stratification, pycnocline depth, surface temperature (seasonality), nitrate, and grazing. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate

No description available.

This study was a comparative study of Plankton of Lake Dallas and the three main source streams. Based on the analysis of data, which was presented relative to the organisms taken from the lake and from the source streams, the results obtained are discussed, the Plankton seem to be largely autogenetic in Lake Dallas, the source streams Elm Fork and Clear Creek form a dilution process.

No description available.

The purpose of this investigation is to attempt to relate the distribution and periodicity of the plankton to the variations in the biological, chemical, and physical factors.

The present study investigated spatial and temporal relationships between fluctuations in the abundance of Atlantic salmon (Salmo salar L.) and plankton records from the Continuous Plankton Recorder (CPR) in the North Atlantic Ocean. Analyses that examined co-variation in time series of salmon pre-fishery abundance (PFA) from fishing nations on both sides of the North Atlantic revealed a high degree of common variation between neighbouring nations for abundance of one sea winter salmon (1SW) and a common decline in the long-term abundance trends for multi-sea winter salmon (MSW). An appraisal of the data attributes for a selection of plankton taxa sampled by the CPR, corresponding to seasonal abundance in specific regions, indicated that these data capture useful spatial and temporal information on the abundance of the sampled taxa. Spatial interpolations were carried out using Data-Interpolating Variational Analysis (DIVA) for planktonic taxa that have been proven to relate to Atlantic salmon in previous studies, namely Calanus finmarchicus, Euphausiacea and Hyperiidae. Geographical boundaries were established for distinct populations of Calanus finmarchicus and for distinct aggregations of species in the cases of the Euphausiacea and the Hyperiidae. This knowledge was enhanced with information on the likelihood of persistence of these populations obtained by analysing the coherency of their seasonal cycles of abundance. This study detected strong relationships, in the form of long-term correlations, between the three selected plankton taxa (Calanus finmarchicus, Euphausiacea, Hyperiidae) and the diatom component of phytoplankton. These results indicated that the population dynamics of plankton species assemblages in these regions are influenced by common biotic and abiotic factors. Significant relationships were found between pre-fishery abundance PFA estimates for post-smolt salmon and Hyperiid amphipods. The relationships detected were particularly strong for 1SWsalmon of British and Icelandic origin at a lag of 1 year, i.e. corresponding to effects on the early phase of migration at sea. Relationships detected corresponding to the Euphausiacea and Calanus finmarchicus were more prevalent at lag-0 after the first winter at sea i.e. they relate to effects on the adult salmon. The results corresponding to MSW salmon also provided some indication of carry-over effects from the early phase of migration on adult survival. This work provided support for the hypothesis that early marine mortality is critical to the overall dynamics of salmon populations. Such information on ecosystem interactions is needed to improve the current knowledge on factors relating to salmon survival at sea. This information can be used to fine-tune important parameters of predictive models for stock management or conservation of salmon, especially in the face of the pressures of climate change.