Oceanography and Atmospheric Sciences and Meteorology Commons^™

Phytoplankton Blooms: Their Occurence And Composition Within Virginia's Tidal Tributaries, Harold G. Marshall, Todd A. Egerton

Biological Sciences Faculty Publications

Sporadic algal bloom development within a 10 year monitoring program in Virginia tidal tributaries of Chesapeake Bay is reviewed. These blooms were common events, characteristically producing a color signature to the surface water, typically short lived, occurring mainly from spring into autumn throughout different salinity regions of these rivers, and were produced primarily by dinoflagellates. The abundance threshold levels that would identify bloom status from a non-bloom presence were species specific, varied with the taxon's cell size, and ranged from ca. 10 to 10(4) cells mL(-1). Among the most consistent sporadic bloom producers were the dinoflagellates Akashiwo sanguinea, Cochlodinium …

Modeling Gag Grouper (Mycteroperca Microlepis) In The Gulf Of Mexico: Exploring The Impact Of Marine Reserves On The Population Dynamics Of A Protogynous Grouper, Robert D. Ellis

LSU Master's Theses

The gag grouper (Mycteroperca microlepis) population in the Gulf of Mexico supports both a commercial and recreational fishery but has experienced a decrease in the male to female sex ratio over the past thirty years. Protogynous fish populations naturally have a smaller male to female ratio than gonochoristic fish populations; however the decline in the gag population is such that sperm limitation may be occurring. In an effort to correct the decline in sex ratio, fishery managers have recently implemented two marine reserves designed specifically to protect gag spawning aggregations. Results from two population models (an age-structured model and an …

Cbod₅ Treatment And Nitrogen Transformations Of The Marshland Upwelling System In Intermediate And Saltwater Marshes, Lorna Anne Putnam

LSU Doctoral Dissertations

The marshland upwelling system (MUS) was designed to treat domestic wastewater from coastal dwellings where conventional methods are inadequate due to high water tables, poor hydraulic soil conditions, anaerobic soils, and saline groundwater. Currently there is no adequate treatment system available and coastal dwellings are contributing to water quality problems. This study focused on determining the treatment effectiveness of the MUS for organic matter and understanding the specific processes involved in nitrogen treatment.

The treatment of organic matter, measured as five-day carbonaceous biological oxygen demand (CBOD₅), was effective in field tests for both saltwater and intermediate marshes. Global …

Anthropogenic And Natural Perturbations On Lower Barataria Bay, Louisiana: Detecting Responses Of Marsh-Edge Fishes And Decapod Crustaceans, Agatha-Marie Fuller Roth

LSU Doctoral Dissertations

Barataria Bay, Louisiana is a dynamic estuary with ongoing disturbances that is in need of restoration. Development and validation of a lower Barataria Bay index of biotic integrity (IBI) for the summer season was the focus of my research. This IBI was created using 2005 data and evaluated with 2006 and 2007 data to demonstrate the feasibility of this approach in coastal Louisiana. The IBI successfully distinguished sites with differing levels of degradation using nine fish metrics. While pursuing this effort, two serendipitous events occurred when an oil spill then a hurricane impacted the study area. This gave me opportunities …

Biogenic Tracers Through The Holocene On The Alaskan Shelf, Carie A. Curry

OES Theses and Dissertations

Dramatic environmental changes in the Arctic Ocean have been observed for the last two decades including changing the amount of sea ice thickness and extent, and increased river discharge. In order to put these and other current day observations into historical context and perhaps reveal mechanisms controlling them, a suite of paleo-proxies were used to analyze two high resolution cores collected on the 2005 HOTRAX expedition. The goals of this research were: (1) develop an analytical method for determining biogenic calcite, (2) identify the major sources of biogenic matter into the system over the Holocene, and (3) assemble the history …