Oceanography and Atmospheric Sciences and Meteorology Commons^™

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 …

Potential Impacts Of Climate Change On Photochemistry Of Zostera Marina L., Billur Celebi

OES Theses and Dissertations

Seagrasses account for approximately 10% of the ocean’s total carbon storage, although photosynthesis of seagrasses is carbon limited at today’s oceanic pH. Therefore, increasing atmospheric CO₂ concentration, which results in ocean acidification/carbonation, is predicted to have a positive impact on seagrass productivity. Previous studies have confirmed the positive influence of increasing CO₂ on photosynthesis and survival of the temperate eelgrass Zostera marina L., but the acclimation of photoprotective mechanisms in this context has not been characterized. This study aimed to quantify the long-term impacts of ocean acidification on photochemical control mechanisms that promote photosynthesis while simultaneously protecting …

Investigating The Spatial Distribution And Effects Of Nearshore Topography On Acropora Cervicornis Abundance In Southeast Florida, Nicole D'Antonio, David S. Gilliam, Brian K. Walker

Marine & Environmental Sciences Faculty Articles

Dense Acropora cervicornis aggregations, or patches, have been documented within nearshore habitats in Southeast Florida (SE FL) despite close proximity to numerous anthropogenic stressors and subjection to frequent natural disturbance events. Limited information has been published concerning the distribution and abundance of A. cervicornis outside of these known dense patches. The first goal of this study was to conduct a spatially extensive and inclusive survey (9.78 km²) to determine whether A. cervicornis distribution in the nearshore habitat of SE FL was spatially uniform or clustered. The second goal was to investigate potential relationships between broad-scale seafloor topography and …

Increasing Shipping Traffic Through The Bering Strait: Challenges Of International Policy In A Rapidly Changing Climate And Managing Impacts To Regional Cetacean Populations, Laura Morse

HCNSO Student Capstones

The Arctic region is experiencing growth in marine traffic as seasonal ice conditions shift to longer periods of open water and vessel improvements that have allowed for transit in heavier ice conditions. Regionally, Russia is improving existing transportation infrastructure to support increased traffic along the Northern Sea Route. As a result of these and other factors, shipping traffic is increasing through the Bering Strait and Bering Sea. Regulating traffic in these areas is more complex than most other areas in US waters given the presence of an international strait subject to international regulation through the International Maritime Organization. The US …

Quantifying The Toxicity Of 1-Methylnaphthalene To The Shallow-Water Coral, Porites Divaricata, For Use In The Target Lipid Model, Nicholas Turner

HCNSO Student Theses and Dissertations

The proximity of coral reefs to coastal urban areas and shipping lanes predisposes corals to petroleum pollution from multiple sources. Previous research has evaluated petroleum toxicity to coral using a variety of methodologies, including monitoring effects of acute and chronic spills, in situ exposures, and ex situ exposures with both adult and larval stage corals. Variability in toxicant, bioassay conditions, species and other methodological disparities among studies prevents comprehensive conclusions regarding the toxicity of hydrocarbons to corals. This research evaluated the 48-hour toxicity of 1-methylnaphthalene to Porites divaricata using a continuous-flow passive dosing system. The range-finding exposure evaluated the dosing …

How Did The Deepwater Horizon Oil Spill Impact Deep-Sea Ecosystems?, Charles R. Fisher, Paul A. Montagna, Tracey Sutton

Marine & Environmental Sciences Faculty Articles

Approximately 90% of the volume of the Gulf of Mexico is contained in water deeper than 200 m, a region where the Deepwater Horizon (DWH) blowout had more impact on ecosystems than any previous oil spill. The remoteness and relative inaccessibility of the deep sea makes documenting even acute impacts to the animals that live in this realm difficult. This article reviews Natural Resource Damage Assessment studies and follow-up work funded as part of the Gulf of Mexico Research Initiative that targeted deepwater pelagic and benthic fauna. Oil was incorporated into the pelagic food web, and a reduction in planktonic …

Using Rare Earth Elements To Constrain Particulate Organic Carbon Flux In The East China Sea, Chin-Chang Hung, Ya-Feng Chen, Shih-Chieh Hsu, Kui Wang, Jianfang Chen, David J. Burdige

OES Faculty Publications

Fluxes of particulate organic carbon (POC) in the East China Sea (ECS) have been reported to decrease from the inner continental shelf towards the outer continental shelf. Recent research has shown that POC fluxes in the ECS may be overestimated due to active sediment resuspension. To better characterize the effect of sediment resuspension on particle fluxes in the ECS, rare earth elements (REEs) and organic carbon (OC) were used in separate two-member mixing models to evaluate trap-collected POC fluxes. The ratio of resuspended particles from sediments to total trap-collected particles in the ECS ranged from 82-94% using the OC mixing …

Presence Of The Cyanotoxin Microcystin In Arctic Lakes Of Southwestern Greenland, Jessica Trout-Haney, Zachary Wood, Kathryn Cottingham

Dartmouth Scholarship

Cyanobacteria and their toxins have received significant attention in eutrophic temperate and tropical systems where conspicuous blooms of certain planktonic taxa release toxins into fresh water, threatening its potability and safe use for recreation. Although toxigenic cyanobacteria are not confined to high nutrient environments, bloom-forming species, or planktonic taxa, these other situations are studied les often studied. For example, toxin production in picoplankton and benthic cyanobacteria—the predominant photoautotrophs found in polar lakes—is poorly understood. We quantified the occurrence of microcystin (MC, a hepatotoxic cyanotoxin) across 18 Arctic lakes in southwestern Greenland. All of the focal lakes contained detectable levels of …

Low Florida Coral Calcification Rates In The Plio-Pleistocene, Thomas C. Brachert, Markus Reuter, Stefan Kruger, James S. Klaus, Kevin P. Helmle, Janice M. Lough

Marine & Environmental Sciences Faculty Articles

In geological outcrops and drill cores from reef frameworks, the skeletons of scleractinian corals are usually leached and more or less completely transformed into sparry calcite because the highly porous skeletons formed of metastable aragonite (CaCO3) undergo rapid diagenetic alteration. Upon alteration, ghost structures of the distinct annual growth bands often allow for reconstructions of annual extension ( =  growth) rates, but information on skeletal density needed for reconstructions of calcification rates is invariably lost. This report presents the bulk density, extension rates and calcification rates of fossil reef corals which underwent minor diagenetic alteration only. The corals derive from …

Agro-Climatic Change, Crop Production And Mitigation Strategies-Case Studies In Arkansas, Usa And Kenya, John Westley Magugu

Graduate Theses and Dissertations

Although climate change impacts vary geographically and temporally, studies at local levels are not readily available for stakeholders to better understand how their local communities would be affected and what remedial measures could be more effective in their local contexts. This dissertation has examined climate change and its impacts in two different local contexts: eastern Arkansas in the USA and Nyando in Kenya. The first part of this dissertation develops agro-meteorological indicators and examines the relationship between agro-meteorological indicators and crop yields in eastern Arkansas between 1960 and 2014. Results reveal that temperature based indicators were more strongly correlated to …

Fish Communities Associated With Cold-Water Corals Vary With Depth And Substratum Type, Rosanna Milligan, Gemma Spence, J. Murray Roberts, David M. Bailey

Marine & Environmental Sciences Faculty Articles

Understanding the processes that drive the distribution patterns of organisms and the scales over which these processes operate are vital when considering the effective management of species with high commercial or conservation value. In the deep sea, the importance of scleractinian cold-water corals (CWCs) to fish has been the focus of several studies but their role remains unclear. We propose this may be due to the confounding effects of multiple drivers operating over multiple spatial scales. The aims of this study were to investigate the role of CWCs in shaping fish community structure and individual species-habitat associations across four spatial …

Evolutionary Potential Of A Dispersal-Restricted Species In Response To Climate Change, Lorena Torres Martinez

Open Access Dissertations

Habitat replacement and fragmentation associated with projected climate change pose a critical threat to global biodiversity. Edaphically limited plant species with restricted dispersal abilities will be especially handicapped to track their optimal climate spatially. Instead, the persistence of these species will depend on their capacity to adapt in situ to novel climate regimes. Here I evaluated the evolutionary potential of Lasthenia fremontii, an annual plant species restricted to ephemeral wetlands called vernal pools in California to adapt to the projected patterns of climate change. Across L. fremontii distribution there is a latitudinal gradient in precipitation which, combined with reduced …

The Impact Of Climate Change In Bangladesh On The Rice Market And Farm Households, Mst Ashrafun Nahar

Graduate Theses and Dissertations

Bangladesh is trying to achieve self-sufficiency in domestic rice production but climate change effects on agricultural production makes it challenging to attain the goal. The country is highly vulnerable to the effects of climate change since it is the major cause to rise in sea level, more warm summer, and happening food and cyclone in the country.

This study develops an Aggregate Farm Household Model to analyze the impact of potential land loss and yield reduction from climate change on production, consumption, prices, welfare, and the ability of government to achieve self-sufficiency in rice production. The model is calibrated to …

Biogeochemistry Of A Saline, Alkaline, Terminal Lake Ecosystem In Transition; Walker Lake, Nevada, Katherine Lynn Willever

UNLV Theses, Dissertations, Professional Papers, and Capstones

Walker Lake is a saline, alkaline, terminal lake ecosystem located in west-central Nevada. For over one hundred years, anthropogenic streamflow diversions within the Walker River Basin have ultimately led to little or no water reaching Walker Lake, the basin’s terminus for water flow. These diversions have resulted in a >46 meter decrease in the lake surface altitude and increases in salinity and dissolved salt constituents that have caused the elimination of native fish species. This study examines how the lack of freshwater inflow has altered the physical, chemical, and microbiological structure of Walker Lake during the lake’s ongoing desiccation.

Between …

Stream Microbial Communities As Potential Indicators Of River And Landscape Disturbance In North-Central Arkansas, Wilson Howard Johnson

Graduate Theses and Dissertations

In the past decade, 29 shale basins have been actively developed across 20 states for extraction of natural gas (NG) via horizontal drilling/hydraulic fracturing (=fracking). This includes ~5000 wells within the Fayetteville shale of north-central Arkansas. Development often impacts both river- and landscapes, and management requires catchment-level evaluations over time, with organismal presence/absence as indicators. For this study next-generation sequencing was used to identify/characterize microbial communities within biofilm of eight Arkansas River tributaries, so as to gauge potential catchment influences. Streams spanned a gradient of landscape features and hydrological flows, with four serving as ‘potentially impacted catchment zones’ (PICZ) and …

Coral Persistence To Ocean Warming Via Developmental Acclimation, Heather L. Schaneen

HCNSO Student Theses and Dissertations

Scleractinian corals are the ‘engineers’ of tropical coral reef ecosystems. Their three-dimensional structure provides habitat for thousands of fish and invertebrate species. The persistence of corals is threatened by climate change. In this study I investigated if corals may be able to increase tolerance to ocean warming through developmental acclimation, i.e. if corals that experience warmer temperatures during embryonic and larval development are better able to cope with higher temperatures later in life. Larvae of the broadcast spawning coral Montastraea cavernosa were raised at ambient (29°C) and future projected ocean warming temperatures (+2°C, 31°C). After larval settlement, coral juveniles from …

Temporal And Spatial Distribution Of Cetacean Strandings Focusing On The Bottlenose Dolphin (Tursiops Truncatus) With A Synthesis Of Potential Causes, April D. Clark

HCNSO Student Capstones

A comprehensive review of the literature and a quantitative statistical analysis of that information are presented. A total of 6,015 cetaceans stranded at 36 locations from 24 peer reviewed articles published between 1999 and 2014 are documented, with the two most common stranding locations being the Canary Islands - accounting for 49 of the total cetacean stranding events - and Cape Cod - accounting for 31 of total cetacean stranding events. The documented cetacean stranding events included 805 for bottlenose dolphins (Tursiops truncatus) at a total of ten locations from 11 peer reviewed articles. When all single stranding …

Transgenerational Effects Of Thermal Stress: Impacts On And Beyond Coral Reproduction, Alyson Kuba

HCNSO Student Theses and Dissertations

Ocean warming causes stress to corals and records reveal that periods of thermal stress are increasing in frequency and severity. Previous studies show that thermal stress negatively impacts the reproductive output of corals. However, the transgenerational impacts of coral bleaching have never been quantified. As a consequence, it is unclear how ocean warming may alter population dynamics due to effects on reproduction and recruitment. This study quantified the transgenerational impacts of thermal stress in Montastraea cavernosa. To assess transgenerational effects of temperature stress during gametogenesis, colonies were exposed to elevated temperature for two weeks four months prior to spawning, …

Can Skeletal Morphology Support New Molecular Phylogenies Of Antedonidae (Crinoidea: Comatulida)?, Brenna Hays

HCNSO Student Theses and Dissertations

Antedonidae (Crinoidea: Comatulida) is the largest of extant crinoid families; it currently includes ~155 accepted species in 50 genera and accounts for ~23% of extant crinoid species (~29% of feather stars) and 27% of genera. Molecular phylogenies have returned the family as polyphyletic, with several clades scattered among non-antedonid sister groups (Hemery 2011, Hemery et al. 2013, Rouse et al. in prep.). Traditional morphological characteristics are thus inadequate for reconstructing relationships among taxa. SEM imaging was used in an effort to discover new diagnostic features that will support the molecular data, focusing on skeletal ossicles within the calyx, specifically the …

Artificial Reefs As Juvenile Fish Habitats In Marinas, Allison Patranella

HCNSO Student Theses and Dissertations

Coastal infrastructure has replaced many vital fish nursery habitats with structures designed without fully mitigating for the loss of the natural ecosystems. This thesis details research focused on the use of small, inexpensive, artificial reef modules as replacement juvenile fish habitat within marinas. My research hypothesis was that the placement of small, structurally complex artificial reef modules would increase fish abundance and species richness relative to unmodified marina seawalls. Non-destructive visual surveys of fishes were completed monthly for 14 months for 12 artificial reef sites and 12 control (unmodified) sites within the Nova Southeastern University Guy Harvey Oceanographic Center (NSU-GHOC) …

Reproductive Ecology Of Dragonfishes (Family: Stomiidae) In The Gulf Of Mexico, Alex D. Marks

HCNSO Student Theses and Dissertations

The most speciose group of fishes in the Gulf of Mexico is the dragonfishes (Family: Stomiidae). These fishes are dominant mesopelagic predators occurring throughout the world’s oceans, including the Antarctic seas. Little is known regarding their reproductive ecology, a consequence attributed to insufficient sample sizes of mature adults due to inadequacies of sampling gear; larger, sexually mature stomiid adults are more adept at net avoidance, thereby obfuscating synoptic reproductive biology studies. Between 2010-2011, the Offshore Nekton Sampling and Analysis Program was initiated in the northern Gulf of Mexico over all four seasons using a discrete-depth sampling system (MOCNESS) and a …

Can Twilight Reefs Usher In A New Dawn For Depauperate Shallow Coral Reefs?, Hunter Kg Noren

HCNSO Student Theses and Dissertations

As shallow reefs continue to decline, scientists are searching for the key to their persistence; as it turns out, they may just need to look deeper. Below many shallow tropical reefs, there exist healthy and more stable mesophotic coral reef communities. The ability of these reefs to act as a refuge for declining shallow populations has garnered significant interest among the scientific community; however, the reproductive and larval aspects necessary for this to occur are unknown. This study assesses the ability of deep reefs to act as a reproductive refuge for shallow counterparts by examining gametic compatibility, viability and larval …

Effects Of Emf Emissions From Undersea Electric Cables On Coral Reef Fishes, Robert F. Jermain

HCNSO Student Theses and Dissertations

The objective of this project was to determine if the electromagnetic field (EMF) emissions from undersea power cables impacted the local and transient marine life, with an emphasis on reef fishes. The work was done at South Florida Ocean Measurement Facility of Naval Surface Warfare Center, Carderock Division, Broward County, Florida. This facility functions as the hub for a range of active undersea detection and data transmission cables. It has multiple active submarine power cables that extend several miles offshore and which can deliver power and enable data transmission to and from a range of acoustic and EMF sensors. The …

Using Regression-Based Effect Size Meta-Analysis To Investigate Coral Responses To Climate Change, Niklas Alexander Kornder

HCNSO Student Theses and Dissertations

Attempts to quantify the effects of ocean acidification and warming (OAW) on scleractinian corals provide a growing body of response measurements. However, placing empirical results into an ecological context is challenging, owing to variations that reflect both natural heterogeneity and scientific bias. This study addresses the heterogeneity of climate change induced changes in coral recruitment and calcification. To discern scientific bias and identify drivers of the remaining heterogeneity, 100 publications were analyzed using a combination of weighted mixed effects meta-regression and factorial effect size meta‑analysis. A linear model was applied to quantify the variation caused by differing stress levels across …

Reducing Pollen Dispersal Using Forest Windbreaks, Carol Auer, Thomas Meyer, Vernie Sagun

Plant Science Articles

The adoption of genetically engineered (GE) crops has created a demand for practical methods to mitigate pollen dispersal and gene flow. The goal of this project was to measure the ability of a narrow forest windbreak to reduce downwind pollen fluxes from switchgrass (Panicum virgatum L.), a North American grass and model biofuels feedstock. Switchgrass fields were established in two identical plots where one had a forest windbreak and the other was in an open (control) site. Switchgrass reproduction, pollen dispersal, wind speed, and wind direction were measured over two years. Daily release of switchgrass pollen peaked at 11:00-13:30 …

Combinatory Effect Of Changing Co2, Temperature, And Long-Term Growth Temperature On Isoprene Emissions, Michael Cole

DePaul Discoveries

Isoprene, the most abundant hydrocarbon in the atmosphere, plays a significant role in atmospheric chemistry. Its reactions with NO_x lead to the formation of ozone in the lower troposphere, which is harmful to plants and detrimental to human health. As air temperatures and CO₂ concentrations increase with climate change, it is uncertain how isoprene emissions from plants will respond. We hypothesized that isoprene emissions will increase with the combination of increasing temperature and CO­₂ concentrations. We predict that oaks grown at a higher temperature will exhibit an increase in isoprene emissions with combined short-term increases in temperature …

The Correlation Between Basal Isoprene Emissions And Climate Of The Native Range Across Oak Species, Mary J. Babiez

DePaul Discoveries

Isoprene is a biogenic volatile organic compound that is emitted by various plant species and plays an important role in the chemistry of the atmosphere. When it reacts with pollutants in the air, such as nitrogen oxides, the precursor to ozone (O₃) is formed. In this experiment, we measured leaf emissions from 20 different oak species at the Morton Arboretum (Lisle, Illinois). The aim was to better understand differences in isoprene emissions across oak species. Since emissions have been found to protect leaves against brief periods of heat stress, we hypothesized that oaks native to areas with greater …

Monitoring And Mitigation Of Elevated Co2 Impacts Using Microalgae, Terry-Rene Wiesner Brown

USF Tampa Graduate Theses and Dissertations

Climate change is arguably the greatest environmental and economic challenge of our time. There are considerable documented and projected impacts to both human and natural systems as a result of climate change. These impacts include changes in temperature, sea level, precipitation patterns, and biogeography of ecologically and economically relevant species, including pathogens. One of the main drivers of climate change is elevated levels of atmospheric carbon dioxide (CO₂), a greenhouse gas. Since pre-industrial times, atmospheric CO₂ levels have increased from approximately 280 ppm to over 400 ppm, as a result of fossil fuel combustion, cement production and …

Beach Nourishment: Effects On The Hatching & Emergence Success Rates Of Leatherback (Dermochelys Coriacea), Loggerhead (Caretta Caretta), And Green (Chelonia Mydas) Sea Turtles, Jenna Caderas

HCNSO Student Theses and Dissertations

Broward County, Florida is a popular tourism destination. Due to its popularity, much of the shoreline has been modified and natural habitats were replaced with infrastructure such as houses, condominiums, resorts, and restaurants. The same Broward County beaches utilized by tourists and residents are important for three species of nesting sea turtles, including the Leatherback, Dermochelys coriacea, Loggerhead, Caretta caretta, and Green, Chelonia mydas, Turtles. The Broward County Sea Turtle Conservation Program (BCSTCP) collects yearly data in order to study these endangered reptiles. Increased anthropogenic effects including further coastal development (public & private), public beach events, public beach access, as …