Life Sciences Commons^™

Vertical Distribution Of Phytoplankton Populations Along The Northeastern Continental Shelf Margin Of The United States, Bruce Burwell Wagoner

Biological Sciences Theses & Dissertations

A study of phytoplankton vertical distribution at six stations along the northeast continental shelf of the United States was conducted in April 1984.

A total of 168 taxa were identified from nine phylogenetic groups collected at depths up to 150 m. Highest cell concentrations and cell volumes were in the upper 30 m. Greatest cell concentrations were produced by diatoms and a pico-nanoplankton component, with cell volumes mainly the product of diatoms and dinoflagellates. A high degree of variability was observed between phylogenetic groups within each station, but less variability was noted for phylogenetic categories at different stations.

Little difference …

Interactions Between Aquatic Chromogenic Bacteria And Pathogenic Vibrio Spp., John Louis Harris

Biological Sciences Theses & Dissertations

Interactions between populations inhabiting an ecosys­tem are responsible, in large part, for determining which species coexist in that ecosystem. In this study, interac­tions between selected Vibrio species, V. alginolyticus and V. anguillarum, and marine heterotrophic, chromogenic bac­teria in aquatic microcosms were investigated. The ultimate goal of this project was to evaluate the feasibility of ex­ ploiting competitive interactions as a means to biologically control growth of the pathogenic marine bacteria, V. alginolyticus and V. anguillarum. In the majority of ex­periments (14/16), if chromogenic species were allowed to develop stable populations before a Vibrio spp. was intro­duced into a …

Seasonal Phytoplankton Assemblages In The Nansemond River, Virginia, Cindy Eleanor Shomers

Biological Sciences Theses & Dissertations

A monthly phytoplankton study was conducted on the Nansemond River from November 1984 to October 1985. Light microscopy was utilized to characterize the resident populations, their cell concentrations and to provide a general comparison to other regional studies of river systems considered more polluted. The results divided the flora into two major categories. The first group was a pico-nanoplankton component composed of Cyanobacteria and Chlorophycean cells 1-10 um in diameter. The second group was a microplankton assemblage of Bacillariophyceae, Dinophyceae, Cryptophyceae, Chlorophyceae, Cyanobacteria and Euglenophyceae. The pico-nanoplankton had a unimodal abundance pattern with peak concentrations occurring in spring. The microplankton …

A Simple Solid-Phase Electrophoretic Procedure For The Separation Of Plasmid Dna, Linda Ann Simurra

Biological Sciences Theses & Dissertations

A method was developed for extraction of plasmid DNA from bacterial cells embedded in agarose blocks. Cell - containing blocks were treated with various lysing reagents and inserted into the wells of an agarose gel. Upon electrophoresis the plasmid DNA migrated out of the embedding block and into the gel leaving intact chromosomal DNA in the well. This method was tested with various organisms and found to be effective for plasmid isolation. In comparison to "traditional" procedures, this new method is less tedious since chemical separation of plasmids is not required prior to electrophoresis. Also, a higher yield of plasmid …