Life Sciences Commons^™

Marine Tardigrades From South Carolina, Usa, Paul J. Bartels, Lilvia J. Bradbury, Diane R. Nelson

Journal of the South Carolina Academy of Science

Until now, there have been only three studies of marine tardigrades from South Carolina, USA. The Fall 2015 invertebrate zoology class from Warren Wilson College collected four sediment samples from Huntington Beach State Park: shallow beach sand, deep beach sand, shallow salt marsh sediment, and deep salt marsh sediment. No tardigrades were found in the salt marsh, but two species were found in the beach samples. Batillipes pennaki Marcus, 1946 was found in shallow and deep beach sand, and three specimens of a potentially new species of Stygarctus Schulz, 1951 were found in the deep beach sand at groundwater level. …

Causes And Consequences Of Individual Phenotypic Differences In Brachyuran Crabs With A Focus On Behavior, Benjamin A. Belgrad

Theses and Dissertations

Individual variation defines almost every morphological, physiological, and behavioral aspect of populations and is a fundamental component of many ecosystem processes. Recent work indicates that accounting for these individual differences can enhance our ability to predict community responses to environmental disturbances which is becoming increasingly important in an era of extraordinary global change. However, our understanding of how different individual characteristics are connected to each other and governed by the environment remains limited.

This study sought to evaluate the relationship between individual behavior, physiological condition, and local habitat for Brachyuran crabs as well as the subsequent strength of their predator-prey …

The Energetic Consequences Of Temperature Variation And Sequential Autotomization For The Stone Crab, Menippe Spp., Eric R. Hancock

Theses and Dissertations

The stone crab, Menippe spp., is harvested in a claw only fishery along the Gulf and southeastern Atlantic coasts of the United States. As climate change continues to warm these areas, crabs are forced to cope with higher water temperatures and lower dissolved O2 concentrations. These altered environmental conditions may influence crab energetics by altering both energy intake and expenditure. To inform fishery sustainability as well as prepare for a potential range expansion of the crab, this study investigates the energetic intake and expenditure of individual stone crabs. Crabs were found to respire 80 and 69% more following the loss …

Differential Response Of Coral Symbiotic Dinoflagellates To Bacterial Toxins That Produce Bleaching In Stony Corals, Diego L. Gil-Agudelo, Yael Ban-Haim, Eugene Rosenberg, Garriet W. Smith

Journal of the South Carolina Academy of Science

Bleaching of corals and other organisms with symbiotic zooxanthellae is a worldwide phenomenon with increasing importance due to global warming scenarios. Bleaching has been historically related to changes in the environment, especially water temperature increase, that stress corals and provoke the release of zooxanthellae. The discovery of Vibrio shilonii, a bacterium causing bleaching under thermal stress in corals of the Mediterranean Sea has changed our thinking about the cause (or explanation) for bleaching of corals worldwide. During this study, we evaluated the effect of a proline rich toxin, extracted from Vibrio shilonii, on zooxanthellae obtained from: Oculina patagonica from the …

Air- Sea Interactions And Ocean Dynamics In The Southwest Tropical Indian Ocean, Jessica Maureen Burns

Theses and Dissertations

The Southwest Tropical Indian Ocean (SWTIO) features a unique, seasonal upward lift of the thermocline, which is known as the Seychelles-Chagos Thermocline Ridge (SCTR; 55°E-65°E, 5°S-12°S). It is known that a high correlation exists between the depth of the thermocline and sea surface temperature (SST; a key ingredient for tropical cyclogenesis). With a particular focus on 2012/2013, this study reveals the dynamic properties of the SCTR that play an important role in the modulation of tropical cyclones in the SWTIO. Phenomena including Indian Ocean Dipole (IOD) and El Niño Southern Oscillation (ENSO) are also well correlated to cyclogenesis through changes …

Marine Phosphorus Biogeochemistry Ecological Insights From Analytical Chemistry, Douglas W. Bell

Theses and Dissertations

The supply of phosphorus (P) directly impacts the growth and speciation of marine microbes (i.e., phytoplankton, bacteria, Archaea). In turn, microbial communities shape the magnitude and rate of marine biogeochemical cycles, ultimately affecting global climate and food production. This dynamic reflects the continuum of temporal and spatial scales at which the marine P cycle operates. However, linking multiple scales of cycling remains a consistent challenge. The primary objective of my dissertation was to gain insight into marine P biogeochemistry, by means of analytical chemistry, at the molecular and environmental scales of cycling. The first component of my research was to …

Molecular Exploration Of Bioavailable Dissolved Organic Matter Across Aquatic Ecosystems, Yuan Shen

Theses and Dissertations

Dissolved organic matter (DOM) in aquatic ecosystems is a large reservoir of reduced carbon that is mostly resistant to degradation. A small fraction of DOM cycles relatively quickly and is biologically utilized on timescales of days to months. This bioavailable DOM (BDOM) supports aquatic food webs, drives major elemental cycles, and is coupled to atmospheric CO2. Despite wide-ranging importance, bioavailability of DOM and its linkages to ecosystem properties (e.g., primary production, nutrients) are poorly characterized, particularly at the ecosystem level. Bioassay experiments are commonly used to determine BDOM, but this approach alters conditions and has limited spatial and temporal coverage. …

Wind Driven Shelf Circulation: Effects Of Shoreline Orientation, Bathymetry, And Surface Cooling, Xiaodong Wu

Theses and Dissertations

The dynamic region extending from the inner- to outer-shelf is the nearshore region where an accurate understanding of the development of cross-shore flows is important as they control the exchange of constituents (e.g., pollutants, larvae, heat and biota) between the coastline and the open ocean. These flows are driven by a variety of forces, including wind and buoyancy. The wind forcing relevant to shelf circulation broadly falls within the synoptic scale of storm events, consisting of frontal systems (cold and warm fronts) and tropical storms. The buoyancy on the shelf is characterized by a vertical stratification or a pronounced cross-shore …

Development Of A Sandwich Hybridization Assay For The Harmful Cyanobacteria Microcystis Spp., Nicole M. Dearth

Theses and Dissertations

Cyanobacteria are responsible for the largest number of harmful blooms (HABs) worldwide. HABs caused by the genus Microcystis pose public health threats because they often occur within close proximity to humans and produce microcystin (hepatotoxin), which can contaminate drinking water and recreational areas. Novel molecular techniques facilitate monitoring, ‘early warnings’ of HAB events, and appropriate management responses. Sandwich hybridization assay (SHA), the technique considered here, directly (no amplification) identifies and quantifies planktonic species using ribosomal RNA (rRNA)-targeted oligonucleotides. This project developed SHA for Microcystis 16S rRNA and validated the assay using laboratory cultures and samples from a multi-specific cyanobacteria bloom …

The Influence Of Phytoplankton Size And Community Composition On Carbon Cycling And Planktonic Food Webs In The Sargasso Sea, Bridget Elise Cotti-Rausch

Theses and Dissertations

The Sargasso Sea is a dynamic physical environment located in the western North Atlantic where strong seasonal variability combines with forcing by mesoscale (~100 km) eddies. These drivers determine nutrient, light, and temperature regimes, and ultimate the size, composition and productivity of the phytoplankton community. My general objective was to determine how the structure and function of planktonic communities affected carbon export from the surface ocean in the Sargasso Sea. On four cruises (2011 and 2012; one eddy per cruise), I investigated links between water column structure, plankton community composition, size, and primary production (PP). I then combined PP data …