Oceanography Commons^™

Eukaryotic Microbes, Principally Fungi And Labyrinthulomycetes, Dominate Biomass On Bathypelagic Marine Snow, Alexander B. Bochdansky, Melissa A. Clouse, Gerhard J. Herndl

OES Faculty Publications

In the bathypelagic realm of the ocean, the role of marine snow as a carbon and energy source for the deep-sea biota and as a potential hotspot of microbial diversity and activity has not received adequate attention. Here, we collected bathypelagic marine snow by gentle gravity filtration of sea water onto μm filters from similar to 1000 to 3900 m to investigate the relative distribution of eukaryotic microbes. Compared with sediment traps that select for fast-sinking particles, this method collects particles unbiased by settling velocity. While prokaryotes numerically exceeded eukaryotes on marine snow, eukaryotic microbes belonging to two very distant …

The Effects Of Thermal Stress On Fluorescent Protein Expression In An Indo-Pacific Scleractinian Coral Species, Acropora Tenuis, Anna Knochel

Independent Study Project (ISP) Collection

The scleractinian coral species that so heavily define tropical coral reefs are increasingly threatened by anthropogenic global warming. Rising sea surface temperatures in combination with light stress causes the photosynthetic breakdown of the coral’s algal symbiont, Symbiodinium. Corals have developed a number of physiological responses to handle acute stressors, such as the production of ultraviolet-protecting amino acids, heat shock proteins, the ability to shift symbionts, and the production of fluorescent proteins. The latter has been thought to play a photoprotective role in the coral holobiont, and studies have shown evidence that corals orient these pigments to divert harmful light away …

Sea Surface Temperature Rises Shift Migration Patterns Due To Ecosystem Changes, Alexia Skrbic, Hesham El-Askary

Student Scholar Symposium Abstracts and Posters

The continuing climate change is negatively impacting ecosystems, specifically oceans which are declining and food webs are being altered by the increase of greenhouse gases. The increase of the carbon dioxide and other greenhouse gases is increasing sea surface temperature of the world’s oceans. Certain organisms lower on the food chain like phytoplankton and zooplankton are directly affected by the warming which alters how they process nutrients and their productivity. The limited amount of these primary producers in the oceans and specifically the location they inhabit directly affects all the organisms above them on the food chain. Several marine animals …

Modern Fair-Weather And Storm Sediment Transport Around Ship Island, Mississippi: Implications For Coastal Habitats And Restoration Efforts, Eve Rettew Eisemann

Master's Theses

The Mississippi – Alabama barrier island chain is experiencing accelerated sea level rise, decreased sediment supply, and frequent hurricane impacts. These three factors drive unprecedented rates of morphology change and ecosystem reduction. All islands in the chain have experienced land loss on the order of hectares per year since records began in the 1840s. In 1969, Hurricane Camille impacted as a Category 5, breaching Ship Island, and significantly reduced viable seagrass habitat. Hurricane Katrina impacted as a Category 3 in 2005, further widening Camille Cut. To better understand the sustainability of these important islands and the ecosystems they support, sediment …

Bloom Or Bust: Retrospective Analysis Of The Giant Jellyfish, Nemopilema Nomurai (Scyphozoa: Rhizostomeae), Ecology In The East Asian Marginal Seas, Naomi Yoder

Master's Theses

The Giant Jellyfish, Nemopilema nomurai, is a large-bodied bloom-forming jellyfish that occurs in the semi-enclosed basins of the East Asian Marginal Seas. N. nomurai has bloomed more frequently in the past 20 years than in any period previously recorded. In Japan, recent N. nomurai blooms were responsible for millions of dollars in lost revenue and equipment damage to commercial fisheries alone. This study statistically analyzed 21 environmental factors in connection with N. nomurai occurrence (using occurrence as a proxy for blooms). Eight factors resulted in a statistically significant or marginally significant (p ≤ 0.10), linear or non-linear relationship with …

Fish Diversity And Coral Health Of Tanzania's Reefs: A Comparative Study Between The Ushongo Village Reef And The Fungu Zinga Reef Over Time, Della Turque, Corinne Casper

Independent Study Project (ISP) Collection

The world’s oceans are becoming increasing acidic due to global climate change, posing a threat to marine ecosystems, including coral carbonate systems. Environmental threats are exacerbated by human development stressors as well: growing populations, dependency on marine resources, and unsustainable practices invaluable marine ecosystems at risk. Tanzania’s coral reef system extends for 3580 km2 (Muhando et al. 2008) near the Tanga region, serving over half a million people who are highly dependent on fishing and other marine resources as their livelihoods (Samoilys et. al. 2008). With Tanzania’s population rapidly growing, the unsustainable pressure on coral reefs for sustenance and livelihood …

The Effects Of Sub-Lethal Predation On The Reproductive Output Of Acanthaster Planci (Crown-Of-Thorns Starfish), Emily Mucha

Independent Study Project (ISP) Collection

Wide-scale declines in live coral cover have been observed throughout history. Modern day coral populations face a multitude of environmental disturbances, however one of the most devastating to the reefs in the Indo-Pacific is the crown-of-thorns starfish (Acanthaster planci), which feeds on the tissues of live corals. The rate at which these individuals feed combined with the explosion of populations in times of outbreak have been seen to exert some of the biggest pressures on coral reefs to date. Following recent episodes of crown-of-thorns starfish (COTS) outbreaks, research on the organism has become increasingly prevalent on the scientific …

The Effects Of Sub-Lethal Predation On The Reproductive Output Of Acanthaster Planci (Crown-Of-Thorns Starfish), Emily Mucha

Independent Study Project (ISP) Collection

Wide-scale declines in live coral cover have been observed throughout history. Modern day coral populations face a multitude of environmental disturbances, however one of the most devastating to the reefs in the Indo-Pacific is the crown-of-thorns starfish (Acanthaster planci), which feeds on the tissues of live corals. The rate at which these individuals feed combined with the explosion of populations in times of outbreak have been seen to exert some of the biggest pressures on coral reefs to date. Following recent episodes of crown-of-thorns starfish (COTS) outbreaks, research on the organism has become increasingly prevalent on the scientific …

Effects Of Temperature, Irradiance And Pco2 On The Growth And Nitrogen Utilization Of Prorocentrum Donghaiense, Zhangxi Hu, Margaret R. Mulholland, Ning Xu, Shunshan Duan

OES Faculty Publications

Environmental factors such as temp erature, irradiance, and nitrogen (N) supply affect the growth of Prorocentrum donghaiense, but the interactive effects of these physical factors and the effects of atmospheric CO₂ (pCO₂) on growth and N uptake have not been examined. We compared growth kinetics of P. donghaiense grown on 4 different N substrates (nitrate [NO₃ -], ammonium [NH₄ +], urea, and glutamic acid [glu]) with respect to temperature, irradiance, and pCO₂. Temperature (15 to 30°C) had a positive effect on growth (max. growth rates: 0.17 to 0.65 d …

A Highly Sensitive Underwater Video System For Use In Turbid Aquaculture Ponds, Chin-Chang Hung, Shih-Chieh Tsao, Kuo-Hao Huang, Hsu-Kunag Chang, Fred C. Dobbs

OES Faculty Publications

The turbid, low-light waters characteristic of aquaculture ponds have made it difficult or impossible for previous video cameras to provide clear imagery of the ponds' benthic habitat. We developed a highly sensitive, underwater video system (UVS) for this particular application and tested it in shrimp ponds having turbidities typical of those in southern Taiwan. The system's high-quality video stream and images, together with its camera capacity (up to nine cameras), permit in situ observations of shrimp feeding behavior, shrimp size and internal anatomy, and organic matter residues on pond sediments. The UVS can operate continuously and be focused remotely, a …

The Contribution Of Marine Aggregate-Associated Bacteria To The Accumulation Of Pathogenic Bacteria In Oysters: An Agent-Based Model, Andrew M. Kramer, J. Evan Ward, Fred C. Dobbs, Melissa L. Pierce

OES Faculty Publications

Bivalves process large volumes of water, leading to their accumulation of bacteria, including potential human pathogens (e.g., vibrios). These bacteria are captured at low efficiencies when freely suspended in the water column, but they also attach to marine aggregates, which are captured with near 100% efficiency. For this reason, and because they are often enriched with heterotrophic bacteria, marine aggregates have been hypothesized to function as important transporters of bacteria into bivalves. The relative contribution of aggregates and unattached bacteria to the accumulation of these cells, however, is unknown. We developed an agent-based model to simulate accumulation of vibrio-type bacteria …

Macrobenthic Communities In The Northern Gulf Of Mexico Hypoxic Zone: Testing The Pearson-Rosenberg Model, Shivakumar Shivarudrappa

Dissertations

The Pearson and Rosenberg (P-R) conceptual model of macrobenthic succession was used to assess the impact of hypoxia (dissolved oxygen [DO] ≤ 2 mg/L) on the macrobenthic community on the continental shelf of northern Gulf of Mexico for the first time. The model uses a stress-response relationship between environmental parameters and the macrobenthic community to determine the ecological condition of the benthic habitat. The ecological significance of dissolved oxygen in a benthic habitat is well understood. In addition, the annual recurrence of bottom-water hypoxia on the Louisiana/Texas shelf during summer months is well documented.

The P-R model illustrates the decreasing …

Temporal Variation In Optical Properties Of Chromophoric Dissolved Organic Matter (Cdom) In Southern California Coastal Waters With Nearshore Kelp And Seagrass, Catherine D. Clark, Warren J. De Bruyn, Paige Aiona

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Optical properties of chromophoric dissolved organic matter (CDOM) were measured in surf zone waters in diurnal field studies at a Southern California beach with nearshore kelp and seagrass beds and intertidal plant wrack. Absorption coefficients (aCDOM(300 nm)) ranged from 0.35 m21 to 3.7 m21 with short-term variability<1 h, increases at ebb and flood tides and higher values (6 m21) during an offshore storm event. Spectral slopes (S) ranged from 0.0028 nm21 to 0.017 nm21, with higher values after the storm; S was generally inversely correlated with aCDOM(300 nm). 3-D excitation–emission matrix spectra (EEMs) for samples with lower S values had humic-type peaks associated with terrestrial material (A, C), marine microbial material (M) and protein peaks, characteristic of freshly produced organic material. Samples with high S values had no or reduced protein peaks, consistent with aged material. Fluorescent indexes (f450/f500 >2.5, BIX>1.1) were consistent with microbial aquatic sources. Leachates of senescent kelp and seagrass had protein and humic-type EEM peaks. After solar simulator irradiation (4 h), protein peaks rapidly photochemically degraded, humic-type peak C increased in intensity and peak M disappeared. Optical characteristics of kelp leachates were most similar to field samples, …

Coastal Sediment Elevation Change Following Anthropogenic Mangrove Clearing, Heather Lyn Hayden, Elise F. Granek

Environmental Science and Management Faculty Publications and Presentations

Coastal mangrove forests along tropical shorelines serve as an important interface between land and sea. They provide a physical buffer protecting the coastline from erosion and act as sediment “traps” catching terrestrial sediment, thus preventing smothering of subtidal coral reefs. Coastal development that removes mangrove habitat may impact adjacent nearshore coral reefs through sedimentation and nutrient loading. We examined differences in sediment elevation change between patches of open-coast intact and anthropogenically cleared red mangroves (Rhizophora mangle) on the east side of Turneffe Atoll, Belize, to quantify changes following mangrove clearing. Samples were collected over a 24 month period at five …

Living On The Margin In The Anthropocene: Engagement Arenas For Sustainability Research And Action At The Ocean-Land Interface, B. C. Glavovic, K. Limburg, K-K. Liu, K-C. Emeis, H. Thomas, H. Kremer, B. Avril, J. Zhang, M. R. Mulholland, M. Glaser, D. P. Swaney

OES Faculty Publications

The advent of the Anthropocene underscores the need to develop and implement transformative governance strategies that safeguard the Earth's life-support systems, most critically at the ocean-land interface - the Margin. The seaward realm of the Margin is the new frontier for resource exploitation and colonization to meet the needs of coastal nations and humanity overall. Here, we spotlight the pivotal role of the Margin for planetary resilience and sustainability, highlight priority issues, and outline a research strategy which aims to: (a) better understand Margin social-ecological systems; (b) guide sustainable development of Margin resources; (c) design governance regimes to reverse unsustainable …

Heterotrophic And Autotrophic Contribution To Dinitrogen Fixation In The Gulf Of Aqaba, Eyal Rahav, Barak Herut, Margaret R. Mulholland, Natalia Belkin, Hila Elifantz, Ilana Berman-Frank

OES Faculty Publications

We evaluated the seasonal contribution of heterotrophic and autotrophic diazotrophy to the total dinitrogen (N₂) fixation in the photic zone of a pelagic station in the northern Gulf of Aqaba, Red Sea. N₂ fixation rates were highest during a Trichodesmium bloom in winter (0.7 nmol N l^-1 d^-1), decreased 7-fold 1 wk later throughout the upper 200 m (~0.1 nmol N l^-1) d^-1), and were significantly coupled with both primary and bacterial productivity. N₂ fixation rates were generally higher in the upper 200 m (~0.4 nmol N l^{-1 …}

New Tracer To Estimate Community Predation Rates Of Phagotrophic Protists, Alexander B. Bochdansky, Melissa A. Clouse

OES Faculty Publications

Predation of eukaryotic microbes on prokaryotes is one of the most important trophic interactions on Earth, representing a major mortality term and shaping morphology and composition of prokaryotic communities. Here we introduce and validate a new tracer to determine predation rates on prokaryotes. Minicells of Escherichia coli marked with a bright green fluorescent protein (GFP) vector have many operational advantages over previously used prey analogs such as fluorescently labeled bacteria. GFP-minicells are similar in size to naturally occurring bacteria from a variety of environments including the oligotrophic open ocean and the deep sea. They are relatively stable against microbial and …

Iron Deficiency Increases Growth And Nitrogen-Fixation Rates Of Phosphorus-Deficient Marine Cyanobacteria, Nathan S. Garcia, Feixue Fu, Peter N. Sedwick, David A. Hutchins

OES Faculty Publications

Marine dinitrogen (N²)-fixing cyanobacteria have large impacts on global biogeochemistry as they fix carbon dioxide (CO₂) and fertilize oligotrophic ocean waters with new nitrogen. Iron (Fe) and phosphorus (P) are the two most important limiting nutrients for marine biological N₂ fixation, and their availabilities vary between major ocean basins and regions. A long-standing question concerns the ability of two globally dominant N₂-fixing cyanobacteria, unicellular Crocosphaera and filamentous Trichodesmium, to maintain relatively high N₂-fixation rates in these regimes where both Fe and P are typically scarce. We show that under P-deficient …

How The Presence Of Plastic In The North Pacific Gyre Affects The Growth Of Thalassiosira Through Remote Sensing And Laboratory Replication, Jordynn Brennan, Hesham El-Askary

Student Scholar Symposium Abstracts and Posters

Through the use of remote sensing, we are able to determine the approximate location of the garbage patch in the North Pacific Gyre. Though remote sensing does not penetrate the surface of the ocean, monthly satellite images can be analyzed to determine the rate of growth or rate of decrease of certain parameters, such as atmospheric gases, phytoplankton, and dissolved organic matter. Over the past decade, data from the Goddard Earth Sciences Data and Information Services Center (Giovanni program) has shown a significant increase in dissolved organic matter and chlorophyll a content in the area of the North Pacific Garbage …

Protein Recycling In Bering Sea Algal Incubations, Eli K. Moore, H. Rodger Harvey, Jessica F. Faux, David R. Goodlett, Brook L. Nunn

OES Faculty Publications

Protein present in phytoplankton represents a large fraction of the organic nitrogen and carbon transported from its synthesis in surface waters to marine sediments. Yet relatively little is known about the longevity of identifiable protein in situ, or the potential modifications to proteins that occur during bloom termination, protein recycling and degradation. To address this knowledge gap, diatom-dominated phytoplankton was collected during the Bering Sea spring blooms of 2009 and 2010, and incubated under darkness in separate shipboard degradation experiments spanning 11 and 53 d, respectively. In each experiment, the protein distribution was monited over time using shotgun proteomics, …

A Comprehensive Evaluation Of C25 Highly Branched Isoprenoid Alkenes Of Marine Diatoms As Proxies For Sea Ice Extent In The Arctic Ocean, Tetiana Muniak

OES Theses and Dissertations

Sea Ice extent is one of the major factors regulating carbon cycling and ecosystem function in the modern Arctic Ocean. It is an essential component of climate models and is crucial for the evaluation of various oceanographic processes that influence a particular region. Yet it is also one of the most difficult attributes of the ocean with respect to our ability for its accurate reconstruction from paleo records. The lack of the detailed records prior to satellite information has encouraged the development of new proxy records for the reconstruction of past

sea ice conditions. In recent years, a new monounsaturated …

Spatial And Temporal Variability In Net Community Metabolism In The Middle Atlantic Bight, Georges Bank, And Gulf Of Maine: Observations Of Net Heterotrophic Phases In The Highly Productive Coastal Zone, Cory James Staryk

OES Theses and Dissertations

Net community metabolism (NCM), the balance between primary production and community respiration, was measured during two cruises, June 2011 and August 2012, in the Middle Atlantic Bight, Georges Bank and Gulf of Maine. Net heterotrophy was observed in Georges Bank and Gulf of Maine during the June 2011 cruise. During the August 2012 cruise, net heterotrophy was observed in the Middle Atlantic Bight and net autotrophy was observed in Georges Bank and the Gulf of Maine. Dark community respiration increased (DCR) with biomass and temperature. Gross community production (GCP) also increased with Chl a, bicarbonate uptake, and temperature. Net …

Fall 2014, Nsu Oceanographic Center

Currents

No abstract provided.

Spring 2014, Nsu Oceanographic Center

Currents

No abstract provided.

The Impact Of Multiple Nursery Areas On The Population Structure Of Atlantic Menhaden, Brevooria Tyrannus, Kristen A. Anstead

OES Theses and Dissertations

Understanding the population structure and patterns of connectivity in marine fishes is essential when making predictions about a species' resiliency and persistence in an increasingly changing environment. The Atlantic Menhaden Brevoortia tyrannus is a clupeid that plays a critical role in the marine food web and supports one of the largest fisheries on the US East Coast. In addition to a decrease in overall numbers and spawning stock biomass, recruitment levels have remained low since the 1990s. Menhaden use numerous estuaries along the Atlantic coast for juvenile development before recruiting to the adult population and the contribution of each of …

Monitoring Ship Noise To Assess The Impact Of Coastal Developments On Marine Mammals, Nathan D. Merchant, Enrico Pirotta, Tim R. Barton, Paul M. Thompson

Biology - All Scholarship

The potential impacts of underwater noise on marine mammals are widely recognised, but uncertainty over variability in baseline noise levels often constrains efforts to manage these impacts. This paper characterises natural and anthropogenic contributors to underwater noise at two sites in the Moray Firth Special Area of Conservation, an important marine mammal habitat that may be exposed to increased shipping activity from proposed offshore energy developments. We aimed to establish a pre-develop- ment baseline, and to develop ship noise monitoring methods using Automatic Identification System (AIS) and time-lapse video to record trends in noise levels and shipping activity. Our results …

Effects Of Predation Upon The Long-Spined Sea Urchin Diadema Antillarum By The Spotted Spiny Lobster Panulirus Guttatus, Meredith D. Kintzing, Mark J. Butler Iv

Biological Sciences Faculty Publications

Sea urchins, important herbivores in marine ecosystems, are strongly impacted by both the direct and indirect effects of predation, and the long-spined sea urchin Diadema antillarum is no exception. Once abundant on Caribbean coral reefs, D. antillarum populations were decimated by disease in the early 1980s, and only where their natural predators have been over-fished has D. antillarum recovery been observed. Spiny lobsters (Palinuridae) are predators of sea urchins, and although there are several species of spiny lobster in the Caribbean, only the spotted spiny lobster Panulirus guttatus is restricted to coral reefs where D. antillarum dwells. We investigated the …

Development And Application Of A Gis-Based Long Island Sound Eelgrass Habitat Suitability Index Model, Jamie M.P. Vaudrey, Justin Eddings, Christopher Pickerell, Lorne Brousseau, Charles Yarish

Department of Marine Sciences

The primary objectives of the Eelgrass Habitat Suitability Index Model (EHSI Model) are to assist in the evaluation of sites being considered for eelgrass restoration efforts in the Long Island Sound (LIS) area and to identify areas where water quality issues reduce or eliminate the potential for natural eelgrass colonization. To achieve this goal, geospatial processing of data available from the Long Island Sound area was conducted using ArcGIS v10.0 including the 3D Analyst and Spatial Analyst extensions. The result is a series of maps presented in this report and a GIS-based model available for users to interact with the …

The General Qapp For Long Island Sound Volunteer Coastal Monitoring (With Adoption Form), Jamie M.P. Vaudrey, Kimberly Gallagher

Department of Marine Sciences

The General QAPP for Long Island Sound Volunteer Coastal Monitoring is designed to streamline the process of writing a QAPP for Monitoring Programs in the Long Island Sound area. This document does not replace guidance on developing a program and is not sufficient as a stand-alone document to guide the initial development and sample design process for a monitoring program.

Evaluation Of Current Community-Based Monitoring Efforts And Recommendations For Developing A Cohesive Network Of Support For Monitoring Long Island Sound Embayments., Jamie M.P. Vaudrey, Jamie Alonzo, Adrienne Esposito, Curt Johnson, Maureen Dolan Murphy, Charles Yarish

Department of Marine Sciences

This project focuses on Long Island Sound embayments and represents an exploration of the potential for coordination among community-based water quality monitoring groups, and coordination between community-based groups and data end users, including scientists and managers. Community-based monitoring groups represent a potential valuable source of water quality information. The development of standardized protocols, training methods and reporting procedures will serve to provide end users with the confidence necessary to utilize the data collected as part of community-based monitoring programs. Both groups of stakeholders stand to benefit from this type of coordination with the ultimate benefit being a healthier, better understood …