Marine Biology Commons^™

Effects Of Epiphyte Load On Optical Properties And Photosynthetic Potential Of The Seagrasses Thalassia Testudinum Banks Ex König And Zostera Marina L, Lisa A. Drake, Fred C. Dobbs, Richard C. Zimmerman

OES Faculty Publications

The biomass and optical properties of seagrass leaf epiphytes were measured to evaluate their potential impact on the photosynthetic performance of the seagrasses Thalassia testudinum Banks ex König (turtlegrass) and Zostera marina L. (eelgrass). Turtlegrass was obtained from oligotrophic waters near Lee Stocking Island, Bahamas; eelgrass was collected from a eutrophic environment in Monterey Bay, California. Leaf–epiphyte loads were characterized visually and quantified using measurements of their phospholipid biomass. Light absorption and reflectance of the intact epiphyte layer were determined spectrophotometrically. Turtlegrass epiphytes from the oligotrophic site absorbed a maximum of 36% of incident light in peak chlorophyll absorption …

Extracellular Enzyme Activity And Uptake Of Carbon And Nitrogen Along An Estuarine Salinity And Nutrient Gradient, Margaret R. Mulholland, Cindy Lee, Patricia M. Gilbert

OES Faculty Publications

Amino acid oxidation (AAO) and peptide hydrolysis (PH) are processes affecting the recycling of organic material and nutrients. We compared extracellular AAO and PH rates to C and N uptake rates along estuarine gradients of salinity, nutrients and productivity in the Pocomoke River, a subestuary of the Chesapeake Bay. This estuary is seasonally depleted in inorganic N, and rich in dissolved organic material (DOM) throughout the year. AAO, PH, and N uptake rates measured in 1999 and 2000 were not limited to particular size fractions measured, or to auto- or heterotrophic groups of organisms. At a station near the turbidity …

The Role Of Physical, Chemical, And Microbial Heterogeneity On The Field-Scale Transport And Attachment Of Bacteria, Brian J. Mailloux, Mark E. Fuller, Tullis C. Onstott, James Hall, Hailiang Dong, Mary F. Deflaun, Sheryl H. Streger, Randi K. Rothmel, Maria Green, Donald J. P. Swift, Jon Radke

OES Faculty Publications

A field-scale bacterial transport experiment was conducted at the Narrow Channel Focus Area of the South Oyster field site located in Oyster, Virginia. The goal of the field experiment was to determine the relative influence of subsurface heterogeneity and microbial population parameters on flow direction, velocity, and attachment of bacteria at the field scale. The field results were compared with results from laboratory-scale column experiments to develop a method for predicting field-scale bacterial transport. The field site is a shallow, sandy, unconfined, aerobic aquifer that has been characterized by geophysical, sedimentological, and hydrogeological methods. Comamonas sp. strain DA001 and a …

Demographic Assessment Of The Blue Crab (Callinectes Sapidus) In Chesapeake Bay Using Extractable Lipofuscins As Age Markers, Se-Jong Ju, David H. Secor, H. Rodger Harvey

OES Faculty Publications

The blue crab (Callinectes sapidus) plays an important economic and ecological role in estuaries and coastal habitats from the Gulf of Mexico to the east coast of North America, but demographic assessments are limited by length-based methods. We applied an alternative aging method using biochemical measures of metabolic byproducts (lipofuscins) sequestered in the neural tissue of eyestalks to examine population age structure. From Chesapeake Bay, subsamples of animals collected from the 1998-99 (n-769) and 1999-2000 (n=367) winter dredge surveys were collected and lipofuscin was measured. Modal analysis of the lipofuscin index provided separation into three modes, whereas carapace-width …

Shallow-Water Reefs In Transition: Examples From Belize And The Bahamas, H. Allen Curran, Benjamin J. Greenstein

Arts & Sciences Faculty Publications

The plight of coral reefs throughout the Caribbean region has been widely reported by reef scientists. A variety of causes has lead to reefal decline, particularly in shallow waters. This study compares the responses of shallow-water reefs in Belize and the Bahamas to outbreaks of white­ band disease (WBD) and traces changes on these reefs to the early 2000s.

Prior to the mid-1980s, reef ridges of the Pelican Cays of Belize were constructed of luxu­ riant stands of Acropora cervicomis. As else­ where, this species suffered massive mortality in mid-1980s owing to WBD, and dead A. cervicor­ nis substrates were …

Isolation And Characterisation Of Microsatellites In The Asian Arowanas, Scleropages Formosus, Janethi Sivananthan

Student Works (2000-2009)

The Asian Arowana (Scleropages /ormosusu) is a primitive freshwater fish form the Jurassic era. It is very hardy and can live a good half century. Its low fecundity rate (about 30 eggs per batch), coupled with habitat degradation, threaten the future survivability of this fish (Khan et al., 1996). It was once close to extinction. In this study, microsatellites were used to study the allele frequencies, heterozygosity as well as the genetic differences among varieties. To identify microsatellite loci without the expense of library screening, a new strategy has been proposed by Fisher et al. (1996). This approach, called the …