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Full-Text Articles in Physical Sciences and Mathematics

Histopathological Assessment And Comparison Sedimentation And Phosphate Stress On The Staghorn Coral, Acropora Cervicornis, Erin Christine Hodel Dec 2007

Histopathological Assessment And Comparison Sedimentation And Phosphate Stress On The Staghorn Coral, Acropora Cervicornis, Erin Christine Hodel

HCNSO Student Theses and Dissertations

Traditional coral reef monitoring efforts lack assessment of coral health at tissue and cellular levels. This thesis investigated tissue, cellular, and gross morphological responses of the Caribbean staghorn coral, Acropora cervicornis, to elevated sedimentation and phosphate using state-of-the-art histological techniques. Branch fragments of A. cervicornis were collected offshore Broward County, FL, acclimated for 12 weeks, subjected to a 4-week experimental period, and given a 1-week recovery period in laboratory aquaria. Treatments consisted of high doses (200 mg cm-2 day-1) of sedimentation (S), phosphate (4 μM) (P), and a combination of these two (S + P), in …


Limb Regeneration After Multiple Autotomy And Coxae Removal In The Blue Crab Callinectes Sapidus, Jennifer Ambler Oct 2007

Limb Regeneration After Multiple Autotomy And Coxae Removal In The Blue Crab Callinectes Sapidus, Jennifer Ambler

OES Theses and Dissertations

This study investigated limb regeneration in the juvenile blue crab, Callinectes sapidus, specifically the role of the coxa and pedal nerve innervation of the regenerative limb bud over time. The coxa is a leg segment that has been defined as the source of positional, cellular, and neuronal information needed for limb regeneration in brachyuran crabs. This study indicates that removal of coxae under regenerative and non-regenerative conditions did not deter limb regeneration. The coxa is not the exclusive location of limb regenerative information since limbs re-grew with normal positional and functional arrangement in 86% of crabs showing regeneration at removal …


Interactions Between Phytoplankton And Bacteria In The Uptake Of Organic Compounds, Andrea Michel Rocha Apr 2007

Interactions Between Phytoplankton And Bacteria In The Uptake Of Organic Compounds, Andrea Michel Rocha

OES Theses and Dissertations

The most common methods for estimating bacterial productivity are [3H]-leucine and [3H]-thymidine incorporation. Uptake of these compounds has been attributed primarily to bacteria; however, because dissolved organic nitrogen may be an important N source for some phytoplankton, the use of these compounds to estimate bacterial productivity needs to be reexamined. In order to ascertain whether phytoplankton could compete with bacteria on relevant timescales and thereby bias bacterial productivity estimates in estuaries, I examined the ability of cultured phytoplankton and size-fractionated natural populations to take up leucine and thymidine in systems seasonally dominated by phytoplankton mixotrophs. In …


Feeding Ecology Of Atlantic Menhaden (Brevoortia Tyrannus) In Chesapeake Bay, Patrick D. Lynch Jan 2007

Feeding Ecology Of Atlantic Menhaden (Brevoortia Tyrannus) In Chesapeake Bay, Patrick D. Lynch

Dissertations, Theses, and Masters Projects

No abstract provided.


Hypoxia And Macoma Balthica: Ecological Effects On A Key Infaunal Benthic Species, William Christopher Long Jan 2007

Hypoxia And Macoma Balthica: Ecological Effects On A Key Infaunal Benthic Species, William Christopher Long

Dissertations, Theses, and Masters Projects

Hypoxia, low dissolved oxygen, is an important environmental stressor in estuarine systems. In this dissertation, I examine the effects of hypoxia on the macrobenthic communities of the York and Rappahannock Rivers, Chesapeake Bay, USA, and in particular its effects on the infaunal clam Macoma balthica. A survey of the macrobenthic community was performed using box-coring before and after hypoxia in 2003 and 2004 in both rivers. Hypoxia was associated with a change in the macrobenthic community towards smaller, shorter-lived, opportunistic species; and a substantial decrease in biomass. M. balthica recruited into all areas of the river but suffered local extinction …


Inactive Sulfide Mounds Of The Manus Basin: Invertebrate Composition And Potential For A Chemoautotrophic Food Web, Kristin Lynn Erickson Jan 2007

Inactive Sulfide Mounds Of The Manus Basin: Invertebrate Composition And Potential For A Chemoautotrophic Food Web, Kristin Lynn Erickson

Dissertations, Theses, and Masters Projects

No abstract provided.


Biogeochemistry And Phytoplankton Dynamics In The Ross Sea, Antarctica, Amy Rebecca Shields Jan 2007

Biogeochemistry And Phytoplankton Dynamics In The Ross Sea, Antarctica, Amy Rebecca Shields

Dissertations, Theses, and Masters Projects

The Ross Sea, Antarctica seasonal phytoplankton bloom is one of the largest in the Southern Ocean. This project focuses on the biological pump, which removes carbon from the surface ocean to the deep ocean through the settling of particulate organic matter, the advection of dissolved organic carbon, and active flux due to vertical migration of zooplankton. The objective of this study was to focus on three interrelated components of the biological pump including sedimentation, photosynthetic rates and grazing. The study was conducted in coordination with the Interannual Variability in the Antarctic-Ross Sea program, which covered the time period between 2001--2005. …


Trophic Ecology And Growth Dynamics Of Striped Bass (Morone Saxatilis) In Chesapeake Bay, With Reference To Mycobacteriosis, Kathleen Anne Mcnamee Jan 2007

Trophic Ecology And Growth Dynamics Of Striped Bass (Morone Saxatilis) In Chesapeake Bay, With Reference To Mycobacteriosis, Kathleen Anne Mcnamee

Dissertations, Theses, and Masters Projects

No abstract provided.


Comparison Of Fish Assemblages Between Mitigation Boulder Reef And Neighboring Natural Hardbottom In Broward County, Florida, Usa, Jessica A. Freeman Jan 2007

Comparison Of Fish Assemblages Between Mitigation Boulder Reef And Neighboring Natural Hardbottom In Broward County, Florida, Usa, Jessica A. Freeman

HCNSO Student Theses and Dissertations

A beach renourishment project was initiated in May 2005 and completed in February 2006 to restore 11.1 km of shoreline in Broward County, Florida, USA. For mitigation of predicted nearshore hardbottom burial, a boulder reef totaling 3.6 ha was deployed in 2003. To examine the replacement value of the mitigation relative to fishes, this study compared fish assemblages on boulder reef to those on adjacent natural hardbottom. Twenty-five natural hardbottom sites and twenty-five boulder reef sites were surveyed six times between March 2005 and August 2007. Two non-destructive visual census methods, a transect count (30 m long x 2 m …


Surface Associated Amoebae On The Ctenophore, Mnemiopsis Sp., Connie S. Versteeg Jan 2007

Surface Associated Amoebae On The Ctenophore, Mnemiopsis Sp., Connie S. Versteeg

HCNSO Student Theses and Dissertations

Previous work by Moss et al. (2001) reported surface associated protists on the ctenophore Mnemiopsis sp. They frequently observed the ciliate Trichodina ctenophorii and a Flabellula-like amoeba attached to the comb plate surface. They noted that the ciliate and the amoeba were found on the subsagittal, subtentacular, and the auricular comb plates. The amoeba had a maximum width of about 15 μm and cells were crescent shaped. Ultrastructural evidence suggested that these protists were parasites although the exact nature of the association remained to be determined. This was the background for the present study.

The present investigation documented the …