Open Access. Powered by Scholars. Published by Universities.®

2015

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 451 - 480 of 551

Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

Evaluating Preferred Direction Tropical Cyclone Track Variability In An Operational Global Ensemble Prediction System, Travis Elless Jan 2015

Evaluating Preferred Direction Tropical Cyclone Track Variability In An Operational Global Ensemble Prediction System, Travis Elless

Legacy Theses & Dissertations (2009 - 2024)

Ensemble forecasts of Tropical Storm Debby and Hurricane Sandy (2012) highlight instances where variability in tropical cyclone (TC) position forecasts are stretched along a preferred direction. The goal of this thesis is to analyze this stretching of variability in a global ensemble prediction system, particularly the European Centre for Medium-Range Weather Forecasts (ECMWF), to determine how often and under what conditions does variability stretching occur, and ultimately what feature(s) are responsible for generating this variability.


The Impacts Of Varability In Temperature And Humidity On Electricity Consumption In New York State, Eric Adamchick Jan 2015

The Impacts Of Varability In Temperature And Humidity On Electricity Consumption In New York State, Eric Adamchick

Legacy Theses & Dissertations (2009 - 2024)

A seasonal harmonic linear regression approach is presented to model the seasonal and diurnal relationships between surface weather observations and electricity load data in New York State. The relationships between dry-bulb, dew point, and wet-bulb temperatures with electricity load were evaluated using the correlation coefficient to test the strength of the relationships, while the regression slope coefficient provided an interpretable scale for those relationships. We found that the strongest seasonal and diurnal relationships occur during boreal summer from the afternoon through the overnight hours, while similar but negative relationships are observed during the winter. Using the same seasonal harmonic linear …


At-Grade Stabilization Structure Impact On Surface Water Quality Of An Agricultural Watershed, Kyle R. Minks, Matthew D. Ruark, Birl Lowery, Fred W. Madison, Dennis Frame, Todd D. Stuntebeck, Matthew J. Komiskey, George J. Kraft Jan 2015

At-Grade Stabilization Structure Impact On Surface Water Quality Of An Agricultural Watershed, Kyle R. Minks, Matthew D. Ruark, Birl Lowery, Fred W. Madison, Dennis Frame, Todd D. Stuntebeck, Matthew J. Komiskey, George J. Kraft

United States Geological Survey: Staff Publications

Decades of farming and fertilization of farm land in the unglaciated/Driftless Area (DA) of southwestern Wisconsin have resulted in the build-up of P and to some extent, N, in soils. This build-up, combined with steep topography and upper and lower elevation farming (tiered farming), exacerbates problems associated with runoff and nutrient transport in these landscapes. Use of an at-grade stabilization structure (AGSS) as an additional conservation practice to contour strip cropping and no-tillage, proved to be successful in reducing organic and sediment bound N and P within an agricultural watershed located in the DA. The research site was designed as …


Interactive Effects Of Climate Change With Nutrients, Mercury, And Freshwater Acidification On Key Taxa In The North Atlantic Landscape Conservation Cooperative Region, Alfred E. Pinkney, Charles T. Driscoll, David C. Evers, Michael J. Hooper, Jeffrey Horan, Jess W. Jones, Rebecca S. Lazarus, Harold G. Marshall, Andrew Milliken, Barnett A. Rattner, John Schmerfeld, Donald W. Sparling Jan 2015

Interactive Effects Of Climate Change With Nutrients, Mercury, And Freshwater Acidification On Key Taxa In The North Atlantic Landscape Conservation Cooperative Region, Alfred E. Pinkney, Charles T. Driscoll, David C. Evers, Michael J. Hooper, Jeffrey Horan, Jess W. Jones, Rebecca S. Lazarus, Harold G. Marshall, Andrew Milliken, Barnett A. Rattner, John Schmerfeld, Donald W. Sparling

United States Geological Survey: Staff Publications

The North Atlantic Landscape Conservation Cooperative LCC (NA LCC) is a public–private partnership that provides information to support conservation decisions that may be affected by global climate change (GCC) and other threats. The NA LCC region extends from southeast Virginia to the Canadian Maritime Provinces. Within this region, the US National Climate Assessment documented increases in air temperature, total precipitation, frequency of heavy precipitation events, and rising sea level, and predicted more drastic changes. Here, we synthesize literature on the effects of GCC interacting with selected contaminant, nutrient, and environmental processes to adversely affect natural resources within this region. Using …


Global Change And Conservation Triage On National Wildlife Refuges, Fred Johnson, Mitchell J. Eaton, Gerard Mcmahon, Raye Nilius, Michael R. Bryant, Dave Case, Julien Martin, Nathan Wood, Laura Taylor Jan 2015

Global Change And Conservation Triage On National Wildlife Refuges, Fred Johnson, Mitchell J. Eaton, Gerard Mcmahon, Raye Nilius, Michael R. Bryant, Dave Case, Julien Martin, Nathan Wood, Laura Taylor

United States Geological Survey: Staff Publications

National Wildlife Refuges (NWRs) in the United States play an important role in the adaptation of social-ecological systems to climate change, land-use change, and other global-change processes. Coastal refuges are already experiencing threats from sea-level rise and other change processes that are largely beyond their ability to influence, while at the same time facing tighter budgets and reduced staff. We engaged in workshops with NWR managers along the U.S. Atlantic coast to understand the problems they face from global-change processes and began a multidisciplinary collaboration to use decision science to help address them. We are applying a values-focused approach to …


A Bird’S- Eye View Of The Usa National Phenology Network: An Off-The-Shelf Monitoring Program, Jherime Kellerman, Caroline A. F. Enquist, Diana L. Humple, Nathaniel E. Seavy, Alyssa Rosemartin, Renée L. Cormier, Lorianne Barnett Jan 2015

A Bird’S- Eye View Of The Usa National Phenology Network: An Off-The-Shelf Monitoring Program, Jherime Kellerman, Caroline A. F. Enquist, Diana L. Humple, Nathaniel E. Seavy, Alyssa Rosemartin, Renée L. Cormier, Lorianne Barnett

United States Geological Survey: Staff Publications

Phenology is central to the biology and ecology of organisms and highly sensitive to climate. Differential responses to climate change are impacting phenological synchrony of inter- acting species, which has been implicated in the decline of migratory birds that rely on seasonal resources. However, few studies explicitly measure phenology of seasonal habitat resources on the breeding and wintering grounds and at stopover sites. While avian monitoring methods are widely standardized, methods of monitoring resource phenology can be highly variable and difficult to integrate. The USA National Phenology Network (USA- NPN) has developed standardized plant and animal phenology protocols and a …


Detection, Occurrence And Fate Of Emerging Contaminants In Agricultural Environments, Daniel D. Snow, David A. Cassada, Shannon L. Bartelt-Hunt, Xu Li, Matteo D'Alessio, Rachel Levine, Yun Zhang, J. Brett Sallach Jan 2015

Detection, Occurrence And Fate Of Emerging Contaminants In Agricultural Environments, Daniel D. Snow, David A. Cassada, Shannon L. Bartelt-Hunt, Xu Li, Matteo D'Alessio, Rachel Levine, Yun Zhang, J. Brett Sallach

Nebraska Water Center: Faculty Publications

A total of 43 papers published in 2014 were reviewed ranging from detailed descriptions of analytical methods, to fate and occurrence studies, to measuring and predicting biological effects for a wide variety of emerging contaminants likely to occur in agricultural environments. New methods and studies on veterinary pharmaceuticals, natural and synthetics steroids, and antibiotic resistance genes in agricultural environments continue to expand our knowledge base on the occurrence and potential impacts of these compounds. This review is divided into the following sections: Introduction, Analytical Methods, Occurrence and Fate, Antibiotic Resistance Genes, and Risk Assessment.


A Novel Approach For Identifying Cloud Clusters Developing Into Tropical Cyclones, Chaunte' W. Lacewell Jan 2015

A Novel Approach For Identifying Cloud Clusters Developing Into Tropical Cyclones, Chaunte' W. Lacewell

Dissertations

Providing advance notice of rare events, such as a cloud cluster (CC) developing into a tropical cyclone (TC), is of great importance. Having advance warning of such rare events possibly can help avoid or reduce the risk of damages and allow emergency responders and the affected community enough time to respond appropriately. Considering this, forecasters need better data mining and data driven techniques to identify developing CCs. Prior studies have attempted to predict the formation of TCs using numerical weather prediction models as well as satellite and radar data. However, refined observational data and forecasting techniques are not always available …


Tipping Point Of A Conifer-Based Ecosystem Under Severe Drought, Kaicheng Huang, Chuixiang Yi, Donghai Wu, Tao Zhou, Xiang Zhao, William J. Blanford, Suhua Wei, Hao Wu, Du Ling, Zheng Li Jan 2015

Tipping Point Of A Conifer-Based Ecosystem Under Severe Drought, Kaicheng Huang, Chuixiang Yi, Donghai Wu, Tao Zhou, Xiang Zhao, William J. Blanford, Suhua Wei, Hao Wu, Du Ling, Zheng Li

Publications and Research

Drought-induced tree mortality has recently received considerable attention. Questions have arisen over the necessary intensity and duration thresholds of droughts that are sufficient to trigger rapid forest declines. The values of such tipping points leading to forest declines due to drought are presently unknown. In this study, we have evaluated the potential relationship between the level of tree growth and concurrent drought conditions with data of the tree growth-related ring width index (RWI) of the two dominant conifer species (Pinus edulis and Pinus ponderosa) in the Southwestern United States (SWUS) and the meteorological drought-related standardized precipitation evapotranspiration index …


Dissolved Oxygen Dynamics During A Phytoplankton Bloom In The Ross Sea Polyna, Bastien Y. Queste, Karen J. Heywood, Walker O. Smith Jr., Daniel E. Kaufman, Timothy D. Jickells, Michael S. Dinniman Jan 2015

Dissolved Oxygen Dynamics During A Phytoplankton Bloom In The Ross Sea Polyna, Bastien Y. Queste, Karen J. Heywood, Walker O. Smith Jr., Daniel E. Kaufman, Timothy D. Jickells, Michael S. Dinniman

CCPO Publications

The Ross Sea polynya is one of the most productive regions in the Southern Ocean. However, limited access and high spatio-temporal variability of physical and biological processes limit the use of conventional oceanographic methods to measure early season primary productivity. High-resolution observations from two Seagliders provide insights into the timing of a bloom in the southern Ross Sea polynya in December 2010. Changes in chlorophyll and oxygen concentrations are used to assess bloom dynamics. Using a ratio of dissolved oxygen to carbon, net primary production is estimated over the duration of the bloom showing a sensitive balance between net autotrophy …


Will Oscillating Wave Surge Converters Survive Tsunamis?, Laura Cooke, P. Christodoulides, E. Renzi, T. Stefanakis, F. Dias Jan 2015

Will Oscillating Wave Surge Converters Survive Tsunamis?, Laura Cooke, P. Christodoulides, E. Renzi, T. Stefanakis, F. Dias

Articles

With an increasing emphasis on renewable energy resources, wave power technology is becoming one of the realistic solutions. However, the 2011 tsunami in Japan was a harsh reminder of the ferocity of the ocean. It is known that tsunamis are nearly undetectable in the open ocean but as the wave approaches the shore its energy is compressed, creating large destructive waves. The question posed here is whether an oscillating wave surge converter (OWSC) could withstand the force of an incoming tsunami. Several tools are used to provide an answer: an analytical 3D model developed within the framework of linear theory, …


Monitoring And Understanding Decadal Scale Changes In Hydrology, Productivity And Carbon Balance In Arctic Tundra Ponds, Christian Gerardo Andresen Jan 2015

Monitoring And Understanding Decadal Scale Changes In Hydrology, Productivity And Carbon Balance In Arctic Tundra Ponds, Christian Gerardo Andresen

Open Access Theses & Dissertations

The Arctic is known for containing large stocks of soil organic carbon, which exists frozen in permafrost in a greenhouse inert state. With predicted future warming in these high northern latitudes, the mobilization of stored soil organic carbon and release to the atmosphere may increase and induce further positive climatic feedbacks. Previous studies have shown that Arctic wetlands and ponds cover a large percentage of the Arctic Coastal Plain and contribute large amounts of carbon to the atmosphere; however, it remains largely unknown how these systems are responding to a warming climate and how this change will impact regional carbon …


Habitat Assessment And Ecological Restoration Design For An Unnamed Tributary Of Stone Dam Creek, Conway, Arkansas, Paige E. Boyle, Mary C. Savin, James A. Mccarty, Marty D. Matlock Jan 2015

Habitat Assessment And Ecological Restoration Design For An Unnamed Tributary Of Stone Dam Creek, Conway, Arkansas, Paige E. Boyle, Mary C. Savin, James A. Mccarty, Marty D. Matlock

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Urbanization can lead to increased sedimentation, erosion, pollution, and runoff into streams. The United States Environmental Protection Agency’s (USEPA) Rapid Bioassessment Protocols (RBPs) are sets of guidelines that can be used to assess a habitat’s sedimentology, hydrology, vegetation, and geomorphology to determine impairment. An unnamed tributary of Stone Dam Creek on the University of Central Arkansas (UCA) campus in Conway, Arkansas runs partially underground and through the urbanized UCA campus watershed. The stream was assessed using the USEPA’s RBPs to determine impairment of the stream, and received a RBP score of 71.2 out of 200 compared to 153.5 in a …


Learning By Doing - Energy Systems Management, Nima Shahriari, Adrian V. Gheorghe Jan 2015

Learning By Doing - Energy Systems Management, Nima Shahriari, Adrian V. Gheorghe

Engineering Management & Systems Engineering Faculty Publications

Climate change concerns have confronted energy policy makers by unprecedented challenges in the 21st century. Revolution of renewable energy technologies, as well as more efficient energy systems, has been promising in the context of global warming. However, these technologies are not maturing and chaning. Consequently planning for development of these resources requires dealing with various multidisciplinary research questions such as financial feasibility of renewable energy projects. Nevertheless, there is considerable lack of education programs offering multidisciplinary approach for addressing the current energy challenges. Based on the 21st evolving energy landscape, an interdisciplinary graduate certificate course work was designed at Old …


Study Of Aerosols’ Characteristics And Dynamics Over The Kingdom Of Saudi Arabia Using A Multisensor Approach Combined With Ground Observations, Ashraf Farahat, Hesham El-Askary, Abdulaziz Al-Shaibani Jan 2015

Study Of Aerosols’ Characteristics And Dynamics Over The Kingdom Of Saudi Arabia Using A Multisensor Approach Combined With Ground Observations, Ashraf Farahat, Hesham El-Askary, Abdulaziz Al-Shaibani

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

This study covers various aspects of the aerosol distribution and characteristics, namely, optical depth climatology, absorption characteristics, and their microphysical properties over four regions in Saudi Arabia using satellite and ground observations including MODIS/Terra and Aqua, OMI, MISR/Terra, AERONET, and CALIPSO for the period April 2003–January 2013. The study includes cities in the North Western, Western, Eastern provinces of Saudi Arabia and in the Rub al Khali desert or Empty Quarter. Satellite and ground observations showed that the dust season extends from April to August with prominent peaks yet with high anthropogenic contribution late summer and early fall. Analysis shows …


Spatial Analyses On Seismo-Ionospheric Precursors Observed By Gim Tec And Demeter During The 2008 M8.0wenchuan Earthquake, Jann-Yenq Liu, Yuh-Ing Chen, Cheng-Chi Huang, Michel Parrot, Sergey Pulintets, Dimitar Ouzounov Jan 2015

Spatial Analyses On Seismo-Ionospheric Precursors Observed By Gim Tec And Demeter During The 2008 M8.0wenchuan Earthquake, Jann-Yenq Liu, Yuh-Ing Chen, Cheng-Chi Huang, Michel Parrot, Sergey Pulintets, Dimitar Ouzounov

Mathematics, Physics, and Computer Science Faculty Articles and Research

An abstract of the "Spatial analyses on seismo-ionospheric precursors observed by GIM TEC and DEMETER during the 2008 M8.0Wenchuan earthquake" paper presented at EGU General Assembly in 2015.


On The Detection And Monitoring Of The Transport Of An Asian Dust Storm Using Multi-Sensor Satellite Remote Sensing, Hesham El-Askary, S. K. Park, M. H. Ahn, A. Prasad, Menas Kafatos Jan 2015

On The Detection And Monitoring Of The Transport Of An Asian Dust Storm Using Multi-Sensor Satellite Remote Sensing, Hesham El-Askary, S. K. Park, M. H. Ahn, A. Prasad, Menas Kafatos

Mathematics, Physics, and Computer Science Faculty Articles and Research

Dynamical and physical features of a long range transported dust event originating in China affecting Korea early March 2008 are examined using an integrative multi-sensor and multi-algorithm approach. Aerosol loadings and their size mode were analyzed over both ocean and land surfaces using the Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol optical depth (AOD), employing standard dark target (DT) and deep blue (DB) algorithms, and the Ångström exponent (AE). Anthropogenic absorbing aerosols and smoke were found to be significant over the Indochina Peninsula, the Philippines and southern China, while a mixture of dust and pollution were predominant over central to northern …


The Value Of Captains’ Behavioral Choices In The Success Of The Surfclam (Spisula Solidissima) Fishery On The U.S. Mid-Atlantic Coast: A Model Evaluation, Eric N. Powell, John M. Klinck, Daphne M. Munroe, Eileen E. Hofmann, Paula Moreno, Roger Mann Jan 2015

The Value Of Captains’ Behavioral Choices In The Success Of The Surfclam (Spisula Solidissima) Fishery On The U.S. Mid-Atlantic Coast: A Model Evaluation, Eric N. Powell, John M. Klinck, Daphne M. Munroe, Eileen E. Hofmann, Paula Moreno, Roger Mann

CCPO Publications

The response of the surfclam Spisula solidissima to warming of the Mid-Atlantic Bight is manifested by recession of the southern and inshore boundary of the clam’s range. This phenomenon has impacted the fishery through the closure of southern ports and the movement of processing capacity north, impacts that may require responsive actions on the part of fishery captains to mitigate a decline in fishery performance otherwise ineluctably accompanying this shift in range. The purpose of this study was to evaluate options in the behavioral repertoire of captains that might provide mitigation. A model capable of simulating a spatially and temporally …


A Southern Hemisphere Sea Level Pressure-Based Precursor For Enso Warm And Cold Events, B. D. Hamlington, R. F. Milliff, H. Van Loon, K.-Y. Kim Jan 2015

A Southern Hemisphere Sea Level Pressure-Based Precursor For Enso Warm And Cold Events, B. D. Hamlington, R. F. Milliff, H. Van Loon, K.-Y. Kim

CCPO Publications

Past studies have described large-scale sea level pressure (SLP) variations in the Southern Hemisphere that lead to El Nino-Southern Oscillation (ENSO) warm and cold events (WE and CE). By relying on this description and the importance of the related variability in the lead up to WE and CE, Southern Hemisphere SLP variations in May-June-July (MJJ) are shown here to be excellent predictors for the peak warm/cold events in sea-surface temperatures (SST) and sea level pressure that mark the mature phase of a warm/cold event in November-January of the same year. Cyclostationary empirical orthogonal functions (CSEOFs) are used to extract the …


The Effect Of Atmospheric Forcing Resolution On Delivery Of Ocean Heat To The Antarctic Floating Ice Shelves, Michael S. Dinniman, John M. Klinck, Le-Sheng Bai, David H. Bromwich, Keith M. Hines, David M. Holland Jan 2015

The Effect Of Atmospheric Forcing Resolution On Delivery Of Ocean Heat To The Antarctic Floating Ice Shelves, Michael S. Dinniman, John M. Klinck, Le-Sheng Bai, David H. Bromwich, Keith M. Hines, David M. Holland

CCPO Publications

Oceanic melting at the base of the floating Antarctic ice shelves is now thought to be a more significant cause of mass loss for the Antarctic ice sheet than iceberg calving. In this study, a 10-km horizontal-resolution circum-Antarctic ocean–sea ice–ice shelf model [based on the Regional Ocean Modeling System (ROMS)] is used to study the delivery of ocean heat to the base of the ice shelves. The atmospheric forcing comes from the ERA-Interim reanalysis (;80-km resolution) and from simulations using the polar-optimized Weather Re- search and Forecasting Model (30-km resolution), where the upper atmosphere was relaxed to the ERA- Interim …


Theoretical Foundation Of Cyclostationary Eof Analysis For Geophysical And Climatic Variables: Concepts And Examples, Kwang-Yul Kim, Benjamin Hamlington, Hanna Na Jan 2015

Theoretical Foundation Of Cyclostationary Eof Analysis For Geophysical And Climatic Variables: Concepts And Examples, Kwang-Yul Kim, Benjamin Hamlington, Hanna Na

CCPO Publications

Natural variability is an essential component of observations of all geophysical and climate variables. In principal component analysis (PCA), also called empirical orthogonal function (EOF) analysis, a set of orthogonal eigenfunctions is found from a spatial covariance function. These empirical basis functions often lend useful insights into physical processes in the data and serve as a useful tool for developing statistical methods. The underlying assumption in PCA is the stationarity of the data analyzed; that is, the covariance function does not depend on the origin of time. The stationarity assumption is often not justifiable for geophysical and climate variables even …


Imber- Research For Marine Sustainability: Synthesis And The Way Forward, Eileen Hofmann, Alida Bundy, Ken Drinkwater, Alberto R. Piola, Bernard Avril, Carol Robinson Jan 2015

Imber- Research For Marine Sustainability: Synthesis And The Way Forward, Eileen Hofmann, Alida Bundy, Ken Drinkwater, Alberto R. Piola, Bernard Avril, Carol Robinson

CCPO Publications

The Integrated Marine Biogeochemistry and Ecosystem Research (IMBER) project aims at developing a comprehensive understanding of and accurate predictive capacity of ocean responses to accelerating global change and the consequent effects on the Earth system and human society. Understanding the changing ecology and biogeochemistry of marine ecosystems and their sensitivity and resilience to multiple drivers, pressures and stressors is critical to developing responses that will help reduce the vulnerability of marine-dependent human communities. This overview of the IMBER project provides a synthesis of project achievements and highlights the value of collaborative, interdisciplinary, integrated research approaches as developed and implemented through …


Acclimation, Adaptation, Traits And Trade-Offs In Plankton Functional Type Models: Reconciling Terminology For Biology And Modelling, Kevin J. Flynn, Michael St. John, John A. Raven, David O. F. Skibinski, J. Icarus Allen, Aditee Mitra, Eileen E. Hofmann Jan 2015

Acclimation, Adaptation, Traits And Trade-Offs In Plankton Functional Type Models: Reconciling Terminology For Biology And Modelling, Kevin J. Flynn, Michael St. John, John A. Raven, David O. F. Skibinski, J. Icarus Allen, Aditee Mitra, Eileen E. Hofmann

CCPO Publications

We propose definitions in terminology to enhance ongoing collaborations between biologists and modellers on plankton ecology. Organism "functional type" should refer to commonality in ecology not biogeochemistry; the latter is largely an emergent property of the former, while alignment with ecology is also consistent with usage in terrestrial science. Adaptation should be confined, as in genetics, to consideration of species inter-generational change; most so-called "adaptive" plankton models are thus acclimative, modifying vital rates in response to stimuli. Trait trade-off approaches should ideally only be considered for describing intra-generational interactions; in applications between generations, and certainly between unrelated species, such concepts …


Impact Of Local Winter Cooling On The Melt Of Pine Island Glacier, Antarctica, P. St-Laurent, J. M. Klinck, M. S. Dinniman Jan 2015

Impact Of Local Winter Cooling On The Melt Of Pine Island Glacier, Antarctica, P. St-Laurent, J. M. Klinck, M. S. Dinniman

CCPO Publications

The rapid thinning of the ice shelves in the Amundsen Sea is generally attributed to basal melt driven by warm water originating from the continental slope. We examine the hypothesis that processes taking place on the continental shelf contribute significantly to the interannual variability of the ocean heat content and ice shelf melt rates. A numerical model is used to simulate the circulation of ocean heat and the melt of the ice shelves over the period 2006–2013. The fine model grid (grid spacing 1.5 km) explicitly resolves the coastal polynyas and mesoscale processes. The ocean heat content of the eastern …


Outcomes Of Asymmetric Selection Pressure And Larval Dispersal On Evolution Of Disease Resistance: A Metapopulation Modeling Study With Oysters, Daphne M. Munroe, Eric N. Powell, Susan E. Ford, Eileen E. Hofmann, John M. Klinck Jan 2015

Outcomes Of Asymmetric Selection Pressure And Larval Dispersal On Evolution Of Disease Resistance: A Metapopulation Modeling Study With Oysters, Daphne M. Munroe, Eric N. Powell, Susan E. Ford, Eileen E. Hofmann, John M. Klinck

CCPO Publications

Marine diseases are a strong selective force that can have important economic and ecological consequences. Larval dispersal patterns, selective mortality and individual growth rates can modulate metapopulation responses to disease pressure. Here, we use a modeling framework that includes distinct populations, connected via larval transport, with varying disease selection pressure and connectivity to examine how these dynamics enhance or inhibit the evolution of disease resistance in metapopulations. Our system, oysters and MSX disease, is one in which disease resistance is highly and demonstrably heritable. Simulations show that under conditions of population isolation (i.e. local retention of larvae) and strong disease …


Otoliths Then And Now: A Study Of Ancient And Modern Fish Populations In Louisiana's Coastal Waters, Marshall James Kormanec Jan 2015

Otoliths Then And Now: A Study Of Ancient And Modern Fish Populations In Louisiana's Coastal Waters, Marshall James Kormanec

LSU Master's Theses

Fish otoliths are composed of inorganic calcium carbonate that aid in gravity and auditory reception. Substances permanently accrete to otolith surfaces in distinct temporal patterns of alternating opaque and translucent rings; these rings are direct proxies for a fish’s age. The objective of my research is to demonstrate how otoliths can be used through time and space to estimate both age and growth of fish. I investigated the spatial differences in age distributions and growth models for red snapper, Lutjanus campechanus, at four natural shelf-edge reefs in the northwestern Gulf of Mexico. Red snapper cohorts ranged 1987-2010 cohorts, with the …


Effects Of Oil Spill And Recovery Of Terrestrial Arthropods In Louisiana Saltmarsh Ecosystem, Wokil Bam Jan 2015

Effects Of Oil Spill And Recovery Of Terrestrial Arthropods In Louisiana Saltmarsh Ecosystem, Wokil Bam

LSU Master's Theses

Saltmarshes are under continuous multiple stressors such as, land loss, erosion, climate change, environmental pollutions and oil spills, which affect the ecological communities inhabiting saltmarshes. Terrestrial arthropods play an important role in the ecology of saltmarshes, affecting primary production and decomposition. Arthropods are often found in the gut contents of Seaside Sparrows and fishes making them an important trophic link to terrestrial and marine vertebrates. Insects and spiders have the potential to be a good indicator of overall marsh health and environment as they are differentially sensitive to oil exposure. Oil pollutants may have significant long-term negative impacts on the …


Fish Biomass And Community Structure Around Standing And Toppled Oil And Gas Platforms In The Northern Gulf Of Mexico Using Hydroacoustic And Video Surveys, Emily Marissa Reynolds Jan 2015

Fish Biomass And Community Structure Around Standing And Toppled Oil And Gas Platforms In The Northern Gulf Of Mexico Using Hydroacoustic And Video Surveys, Emily Marissa Reynolds

LSU Master's Theses

There has been relatively little study of the efficacy of decommissioned oil and gas platforms as artificial reef habitats for fish assemblages in the northern Gulf of Mexico (GOM). A variety of fish species have been reported on these structures, but the species biomass distribution and community structure has not been studied thoroughly. Hydroacoustic and video surveys were conducted quarterly from June 2013 to June 2014 at three standing and two toppled oil and gas platforms located approximately 130 km off the coast of Louisiana at 90 m depth; to gain information about the spatial biomass distribution and community structure …


Oil And Gas Platforms On Ship Shoal, Northern Gulf Of Mexico As Habitat For Reef-Associated Organisms, David Bradley Reeves Jan 2015

Oil And Gas Platforms On Ship Shoal, Northern Gulf Of Mexico As Habitat For Reef-Associated Organisms, David Bradley Reeves

LSU Master's Theses

Nearshore Louisiana has experienced substantial changes within the last half-century, including the annual formation of the world’s second largest hypoxic zone and the construction of thousands of oil and gas platforms (rigs). Ship Shoal and its rigs may provide important substrate in nearshore Louisiana because rigs act as de facto artificial reefs and the shoal’s bottom waters were well oxygenated on 43% of days when surrounding areas were hypoxic. From July to September of 2014, fish assemblages and hydrography were compared at shoal rigs, rigs inshore of the shoal, and rigs offshore of the shoal, and stone crab populations were …


Anthropogenic Impacts On Soil Microbial Processes In Coastal Wetlands: Nutrient Loading And Rising Co2 Levels, Havalend Ellen Steinmuller Jan 2015

Anthropogenic Impacts On Soil Microbial Processes In Coastal Wetlands: Nutrient Loading And Rising Co2 Levels, Havalend Ellen Steinmuller

LSU Master's Theses

Atmospheric carbon dioxide (CO2) levels and global eutrophication are anthropogenic stressors impacting the environment of specific interest in wetland systems. Wetlands occupy a critical interface between terrestrial and aquatic environments. Fertilizer use for agriculture and treated wastewater disposal has increased nutrient loading to wetlands. Conflicting results on impacts of nitrogen loading to coastal wetland soils have been reported, though most studies have investigated short-term impacts of nutrient loading, not long-term integrated impacts. I investigated an 11-year period of nutrient loading on soils in an oligohaline coastal wetland. Nitrogen treatments of 0, 50, 200, and 1200 kg ha-1 yr-1 were paired …