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7,460 full-text articles. Page 161 of 236.

ความสัมพันธ์ระหว่างประชาคมโคพีพอดและปัจจัยสิ่งแวดล้อม บริเวณเกาะสีชัง จังหวัดชลบุรี, วดีพร รัตนานุพงศ์ 2017 คณะวิทยาศาสตร์

ความสัมพันธ์ระหว่างประชาคมโคพีพอดและปัจจัยสิ่งแวดล้อม บริเวณเกาะสีชัง จังหวัดชลบุรี, วดีพร รัตนานุพงศ์

Chulalongkorn University Theses and Dissertations (Chula ETD)

ศึกษาโครงสร้างประชาคมของโคพีพอด ได้แก่ ความหลากชนิด, ความยาวลำตัว และปริมาตรชีวภาพของโคพีพอด บริเวณเกาะสีชัง จังหวัดชลบุรีใน พ.ศ. 2551, 2554 และ 2559 ในช่วงมรสุมตะวันออกเฉียงเหนือ (มกราคม พ.ศ. 2559) ช่วงระหว่างมรสุม หรือ Inter-I (เมษายน พ.ศ. 2559) ช่วงมรสุมตะวันตกเฉียงใต้ (กรกฎาคม พ.ศ. 2559) และช่วงระหว่างมรสุม หรือ Inter-II (ตุลาคม พ.ศ. 2551, ตุลาคมและพฤศจิกายน พ.ศ. 2554 และพฤศจิกายน พ.ศ. 2559) ผลการศึกษาพบโคพีพอดขนาดใหญ่เมโซแพลงก์ตอน 15 ชนิดใน พ.ศ. 2559 รองลงมา 8 ชนิดใน พ.ศ. 2554 และต่ำสุด 5 ชนิดใน พ.ศ. 2551 ขณะที่พบโคพีพอดขนาดไมโครแพลงก์ตอนทั้งสิ้น 18 ชนิดในช่วงมรสุมตะวันออกเฉียงเหนือ พบโคพีพอดขนาดใหญ่ในความหนาแน่นสูงสุดใน พ.ศ. 2559 รองลงมาใน พ.ศ. 2554 และ พ.ศ. 2551 โดยใน พ.ศ. 2559 ช่วงมรสุมตะวันตกเฉียงใต้ และช่วงระหว่างมรุสมเดือนเมษายน พบโคพีพอดมีความหนาแน่นในช่วง 619-678 ตัว/ลูกบาศก์เมตร แต่ในช่วงระหว่างมรุสมพฤศจิกายนและช่วงมรสุมตะวันออกเฉียงเหนือนั้น พบโคพีพอดในความหนาแน่นต่ำระหว่าง 298-397 ตัว/ลูกบาศก์เมตร ส่วนโคพีพอดขนาดเล็กมีความชุกชุมสูงใกล้เคียงกัน (92,417-108,142 ตัว/ลูกบาศก์เมตร) ในช่วงระหว่างมรสุมเมษายนและช่วงมรสุมตะวันตกเฉียงใต้ ส่วนช่วงระหว่างมรสุมเดือนพฤศจิกายนและช่วงมรสุมตะวันออกเฉียงเหนือ มีความหนาแน่นต่ำในช่วง 16,888-29,402 ตัว/ลูกบาศก์เมตร การศึกษาความยาวลำตัว (prosome length) และปริมาตรชีวภาพ (biovolume) พบว่าโคพีพอดเพศเมียเกือบทุกชนิดมีความยาวลำตัวและปริมาตรชีวภาพสูงกว่าเพศผู้ ยกเว้นโคพี-พอดชนิด Acartia erythraea ที่เพศผู้มีความยาวลำตัวและปริมาตรชีวภาพสูงกว่าเพศเมีย ปัจจัยสิ่งแวดล้อมบริเวณเกาะสีชังใน พ.ศ. 2559 มีความแปรปรวนแตกต่างกันในแต่ละช่วงเวลา โดยปัจจัยสิ่งแวดล้อมหลักที่มีอิทธิพลต่อประชาคมโคพีพอด …


Distribution And Habitat Use Of The Golden Crab Chaceon Fenneri Off Eastern Florida Based On In Situ Submersible And Rov Observations And Potential For Impacts To Deep Water Coral/Sponge Habitat, John K. Reed, Stephanie Farrington, Charles Messing, Andrew David 2017 Harbor Branch Oceanographic Institute, Florida Atlantic University

Distribution And Habitat Use Of The Golden Crab Chaceon Fenneri Off Eastern Florida Based On In Situ Submersible And Rov Observations And Potential For Impacts To Deep Water Coral/Sponge Habitat, John K. Reed, Stephanie Farrington, Charles Messing, Andrew David

Gulf and Caribbean Research

This study documents the distribution and habitat preferences of the golden crab, a commercially fished species, in relation to deep-sea coral/sponge ecosystems (DSCEs) at 200-900 m depths off eastern Florida. A total of 386 h of videotapes from 94 submersible and remotely operated vehicle (ROV) dives from 1999 to 2009, covering a total distance of 376 km, were reviewed and characterized for habitat type and presence of crabs. The DSCEs surveyed included Lophelia coral mounds, Miami Terrace, Pourtalès Terrace, and Tortugas Valleys. Video transect data also included environmental surveys of proposed deep-water routes for Liquid Natural Gas (LNG) pipelines, LNG …


Eco-Label Certification: A Case Study Of The Campeche Shrimp Fishery, Mexico, Antonio Di Cintio, Luis Bourillón Moreno 2017 Centre for Resource Management and Environmnental studies

Eco-Label Certification: A Case Study Of The Campeche Shrimp Fishery, Mexico, Antonio Di Cintio, Luis Bourillón Moreno

Gulf and Caribbean Research

The Marine Stewardship Council (MSC) eco—label certifies that seafood comes from a sustainable source. The use of this eco—label lags behind in the developing world, where ecosystem approaches to fishery management have not yet been widely implemented. However, the Food and Agriculture Organization under its REBYC—II LAC project is addressing ecosystem concerns within the shrimp trawl fisheries of a number of developing countries in Latin America and the Caribbean by helping them to improve management of the negative ecosystem impacts by modifying their gear to reduce by—catch and habitat damage. This study investigates how the potential improvements identified by the …


Dredging Land Reclamation Causing Mucus Development In Massive Spherical Corals In The Spratly Islands, South China Sea: The Effects On China’S Fishing Industry, Tiffany K. Ho 2017 Virginia Commonwealth University

Dredging Land Reclamation Causing Mucus Development In Massive Spherical Corals In The Spratly Islands, South China Sea: The Effects On China’S Fishing Industry, Tiffany K. Ho

UROP Posters

Images from Asia Maritime Transparency Initiative depicted huge masses of white coral mucus secreted from coral reefs in the Spratly Islands of the South China Sea, an area where several land reclamation projects are occurring. The purpose of this research was to understand how increased sedimentation levels from the dredging land reclamation method affects mucus development in massive corals, such as Acropora, located in these reefs. Journal articles that focused on the biology of coral mucus, bacterial communities associated with coral tissue, mucus, and seawater, coral mortality from different environment impacts, coral coverage of reefs in Spratly Islands, and symbiotic …


Integration Of Biological Effects, Fish Histopathology And Contaminant Measurements For The Assessment Of Fish Health: A Pilot Application In Irish Marine Waters, Michelle Giltrap, Jenny Ronan, John Bignell, Brett Lyons, Evelyn Collins, Heather Rochford, Brendan McHugh, Evin McGovern, Lorraine Bull, James Wilson 2017 Technological University Dublin

Integration Of Biological Effects, Fish Histopathology And Contaminant Measurements For The Assessment Of Fish Health: A Pilot Application In Irish Marine Waters, Michelle Giltrap, Jenny Ronan, John Bignell, Brett Lyons, Evelyn Collins, Heather Rochford, Brendan Mchugh, Evin Mcgovern, Lorraine Bull, James Wilson

Articles

This study investigates the use of a weight of evidence (WOE) approach to evaluate fish health status and biological effects (BEs) of contaminants for assessment of ecosystem health and discusses its potential application in support of the Marine Strategy Framework Directive (MSFD). External fish disease, liver histopathology and several BEs of contaminant exposure including 7-ethoxy resorufin O-de-ethylase (EROD), acetylcholinesterase (AChE), bile metabolites, vitellogenin (VTG) and alkali labile phosphates (ALP) were measured in two flatfish species from four locations in Ireland. Contaminant levels in fish were generally low with PCBs in fish liver below OSPAR environmental assessment criteria (EAC). There were …


Multiscale Habitat Suitability Modeling For Canary Rockfish (Sebastes Pinniger) Along The Northern California Coast, Portia N. Saucedo 2017 Humboldt State University

Multiscale Habitat Suitability Modeling For Canary Rockfish (Sebastes Pinniger) Along The Northern California Coast, Portia N. Saucedo

Cal Poly Humboldt theses and projects

Detailed spatially-explicit data of the potential habitat of commercially important rockfish species are a critical component for the purposes of marine conservation, evaluation, and planning. Predictive habitat modeling techniques are widely used to identify suitable habitat in un-surveyed regions. This study elucidates the predicted distribution of canary rockfish (Sebastes pinniger) along the largely un-surveyed northern California coast using data from visual underwater surveys and predictive terrain complexity covariates. I used Maximum Entropy (MaxEnt) modelling software to identify regions of suitable habitat for S. pinniger greater than nine cm in total length at two spatial scales. The results of …


Economic Effects Of Pacific Halibut Closures On Businesses On The North Coast And The Age, Growth, And Reproductive Status Of Pacific Halibut In Northern California And Central Oregon, Miki Takada 2017 Humboldt State University

Economic Effects Of Pacific Halibut Closures On Businesses On The North Coast And The Age, Growth, And Reproductive Status Of Pacific Halibut In Northern California And Central Oregon, Miki Takada

Cal Poly Humboldt theses and projects

Traditionally, the recreational fishery for Pacific halibut has been open in California from 1 May through 31 October. In 2014, however, the Pacific halibut fishery was closed in California during the month of August for the first time in history in an effort to reduce harvest and bring total catch closer to what is allocated to our region by the Pacific Fisheries Management Council (PFMC) Catch Sharing Plan. To determine the effects that the closure had on businesses along the North Coast, I conducted an economic impact survey in 2014. The results of the survey showed that fishing-related businesses lost …


Behavioral Responses Of Sub-Adult Atlantic Sturgeon (Acipenser Oxyrinchus Oxyrinchus) To Electromagnetic And Magnetic Fields Under Laboratory Conditions, Andrew McIntyre III 2017 Virginia Commonwealth University

Behavioral Responses Of Sub-Adult Atlantic Sturgeon (Acipenser Oxyrinchus Oxyrinchus) To Electromagnetic And Magnetic Fields Under Laboratory Conditions, Andrew Mcintyre Iii

Theses and Dissertations

Electromagnetic fields (EMF) produced by high voltage (HV), submarine transmission cables leading from offshore wind energy generation facilities could affect foraging or migratory behaviors of electro-receptive fishes, including endangered Atlantic Sturgeon. However, no published studies have quantitatively evaluated the possible behavioral effects of EMF exposure on sturgeon during residence in coastal waters. This study evaluated behavioral responses by sub-adult Atlantic Sturgeon to electromagnetic and magnetic fields under controlled laboratory conditions. Fabricated EMF generators were used to emulate a range of field EMF conditions that migratory fishes could encounter in proximity to submarine HV sources. Sensor arrays and digital video recorders …


Elevated Trace Metal Content Of Prokaryotic Communities Associated With Marine Oxygen Deficient Zones, Daniel C. Ohnemus, Sara Rauschenberg, Gregory A. Cutter, Jessica N. Fitzsimmons, Robert M. Sherrell, Benjamin S. Twining 2017 Old Dominion University

Elevated Trace Metal Content Of Prokaryotic Communities Associated With Marine Oxygen Deficient Zones, Daniel C. Ohnemus, Sara Rauschenberg, Gregory A. Cutter, Jessica N. Fitzsimmons, Robert M. Sherrell, Benjamin S. Twining

OES Faculty Publications

Little is known about the trace metal content of marine prokaryotes, in part due to their co-occurrence with more abundant particulate phases in the upper ocean, such as phytoplankton and biogenic detritus, lithogenic minerals, and authigenic Mn and Fe oxyhydroxides. We attempt to isolate these biomass signals in particulate data from the US GEOTRACES Eastern Pacific Zonal Transect (cruise GP16) in the Eastern Tropical South Pacific (ETSP), which exhibited consistent maxima in P and other bioactive trace metals, and minima in particulate Mn, in the oxygen deficient zones (ODZs) of 13 stations. Nitrite maxima and nitrate deficits indicated the presence …


Frontiers In Otolith Chemistry: Insights, Advances And Applications, B. D. Walther, K. E. Limburg, C. M. Jones, J. J. Schaffler 2017 Old Dominion University

Frontiers In Otolith Chemistry: Insights, Advances And Applications, B. D. Walther, K. E. Limburg, C. M. Jones, J. J. Schaffler

OES Faculty Publications

The rapid proliferation of publications employing chemical assays of fish hard parts, and otoliths in particular, has led to many novel insights into the migration patterns, life history strategies and mixed stock dynamics of fishes across the globe (Campana et al., 2000; Elsdon et al., 2008; Walther & Limburg, 2012). These insights include uncovering diverse migratory strategies within species and populations (Kerr et al., 2009; Hogan et al., 2014; Schoen et al., 2016), quantifying rates of mixing among stocks across management boundaries (Rooker et al., 2008; Walther & Thorrold, 2010) and estimating the relative …


Beyond Zar: The Use And Abuse Of Classification Statistics For Otolith Chemistry, C. M. Jones, M. Palmers, J. J. Schaffler 2017 Old Dominion University

Beyond Zar: The Use And Abuse Of Classification Statistics For Otolith Chemistry, C. M. Jones, M. Palmers, J. J. Schaffler

OES Faculty Publications

Classification method performance was evaluated using otolith chemistry of juvenile Atlantic menhaden Brevoortia tyrannus when assumptions of data normality were met and were violated. Four methods were tested [linear discriminant function analysis (LDFA), quadratic discriminant function analysis (QDFA), random forest (RF) and artificial neural networks (ANN)] using computer simulation to determine their performance when variable-group means ranged from small to large and their performance under conditions of typical skewness to double the amount of skewness typically observed. Using the kappa index, the parametric methods performed best after applying appropriate data transformation, gaining 2% better performance with LDFA performing slightly better …


Expanding Our Understanding Of The Trade In Marine Aquarium Animals, Andrew L. Rhyne, Michael F. Tlusty, Joseph T. Szczebak, Robert J. Holmberg 2017 Roger Williams University

Expanding Our Understanding Of The Trade In Marine Aquarium Animals, Andrew L. Rhyne, Michael F. Tlusty, Joseph T. Szczebak, Robert J. Holmberg

Arts & Sciences Faculty Publications

The trade of live marine animals for home and public aquaria has grown into a major global industry. Millions of marine fishes and invertebrates are removed from coral reefs and associated habitats each year. The majority are imported into the United States, with the remainder sent to Europe, Japan, and a handful of other countries. Despite the recent growth and diversification of the aquarium trade, to date, data collection is not mandatory, and hence comprehensive information on species volume and diversity is lacking. This lack of information makes it impossible to study trade pathways. Without species-specific volume and diversity data, …


The Central Arctic Ocean-Preventing Another Tragedy Of The Commons, Andrew J. Norris, Patrick McKinley 2017 United States Coast Guard Academy

The Central Arctic Ocean-Preventing Another Tragedy Of The Commons, Andrew J. Norris, Patrick Mckinley

Arts & Sciences Faculty Publications

Arctic sea ice is melting, slowly but inexorably. As the ice disappears, mankind will be afforded access to regions and activities, including commercial fishing, that have been inaccessible for our entire recorded history. There is currently no regulatory body or mechanism in the high seas Arctic (also referred to as the central Arctic Ocean) to conserve and manage fish stocks, the distribution and concentration of which are poorly understood, and that might be the target of commercial fisheries. This article examines the extent and nature of ice recession in the Arctic, and its likely effect on the accessibility of central …


Season, But Not Symbiont State, Drives Microbiome Structure In The Temperate Coral Astrangia Poculata., Koty H. Sharp, Zoe A. Pratte, Allison H. Kerwin 2017 Roger Williams University

Season, But Not Symbiont State, Drives Microbiome Structure In The Temperate Coral Astrangia Poculata., Koty H. Sharp, Zoe A. Pratte, Allison H. Kerwin

Arts & Sciences Faculty Publications

BACKGROUND: Understanding the associations among corals, their photosynthetic zooxanthella symbionts (Symbiodinium), and coral-associated prokaryotic microbiomes is critical for predicting the fidelity and strength of coral symbioses in the face of growing environmental threats. Most coral-microbiome associations are beneficial, yet the mechanisms that determine the composition of the coral microbiome remain largely unknown. Here, we characterized microbiome diversity in the temperate, facultatively symbiotic coral Astrangia poculata at four seasonal time points near the northernmost limit of the species range. The facultative nature of this system allowed us to test seasonal influence and symbiotic state (Symbiodinium density in the coral) on microbiome …


Investigating The Effects Of Changes In Light Quality On Different Life History Stages Of Seagrasses, Simone Strydom 2017 Edith Cowan University

Investigating The Effects Of Changes In Light Quality On Different Life History Stages Of Seagrasses, Simone Strydom

Theses: Doctorates and Masters

Seagrass meadows provide crucial ecosystem services to the coastal zone but globally are threatened. Seagrass loss to date has mainly been attributed to anthropogenic activities that reduce light quantity, such as dredging, declining water quality from urban and agricultural run-off and eutrophication. However, light quality (wavelengths of light) is also altered by these anthropogenic stressors as well as natural events. This study consisted of three main components: (1) characterising light quality to which seagrasses are exposed across a local natural estuarine-ocean gradient and with a human impact pressure; (2) the influence of monochromatic light quality (blue λ=451 nm; green λ=522 …


Impact Of The Capillary Pressure-Saturation Pore-Size Distribution Parameter On Geological Carbon Sequestration Estimates, Chu-Lin Cheng, Edmund Perfect, T. Edward Yu, Michael J. Gragg 2017 The University of Texas Rio Grande Valley

Impact Of The Capillary Pressure-Saturation Pore-Size Distribution Parameter On Geological Carbon Sequestration Estimates, Chu-Lin Cheng, Edmund Perfect, T. Edward Yu, Michael J. Gragg

School of Earth, Environmental, & Marine Sciences Faculty Publications

Cost estimates for geologic carbon sequestration (GCS) are vital for policy and decision makers evaluating carbon capture and storage strategies. Numerical models are often used in feasibility studies for the different stages of carbon injection and redistribution. Knowledge of the capillary pressure-saturation function for a selected storage rock unit is essential in applications used for simulating multiphase fluid flow and transport. However, the parameters describing these functions (e.g. the van Genuchten m pore size distribution parameter) are often not measured or neglected compared to other physical properties such as porosity and intrinsic permeability. In addition, the use of average …


Linear And Nonlinear Effects Of Temperature And Precipitation On Ecosystem Properties In Tidal Saline Wetlands, Laura C. Feher, Michael J. Osland, Kereen T. Griffith, James B. Grace, Rebecca J. Howard, Camille L. Stagg, Nicholas M. Enwright, Ken W. Krauss, Christopher A. Gabler, Richard H. Day, Kerrylee Rogers 2017 The University of Texas Rio Grande Valley

Linear And Nonlinear Effects Of Temperature And Precipitation On Ecosystem Properties In Tidal Saline Wetlands, Laura C. Feher, Michael J. Osland, Kereen T. Griffith, James B. Grace, Rebecca J. Howard, Camille L. Stagg, Nicholas M. Enwright, Ken W. Krauss, Christopher A. Gabler, Richard H. Day, Kerrylee Rogers

School of Earth, Environmental, & Marine Sciences Faculty Publications

Climate greatly influences the structure and functioning of tidal saline wetland ecosystems. However, there is a need to better quantify the effects of climatic drivers on ecosystem properties, particularly near climate‐sensitive ecological transition zones. Here, we used climate‐ and literature‐derived ecological data from tidal saline wetlands to test hypotheses regarding the influence of climatic drivers (i.e., temperature and precipitation regimes) on the following six ecosystem properties: canopy height, biomass, productivity, decomposition, soil carbon density, and soil carbon accumulation. Our analyses quantify and elucidate linear and nonlinear effects of climatic drivers. We quantified positive linear relationships between temperature and above‐ground productivity …


Response And Recovery Of A Mixed Tropical Seagrass Assemblage To Variation In The Frequency And Magnitude Of Light Deprivation. Report Of Theme 5 - Project 5.5.3 Prepared For The Dredging Science Node, John Statton, Kathryn McMahon, Rosin McCallum, Gary Kendrick, Paul Lavery 2017 Edith Cowan University

Response And Recovery Of A Mixed Tropical Seagrass Assemblage To Variation In The Frequency And Magnitude Of Light Deprivation. Report Of Theme 5 - Project 5.5.3 Prepared For The Dredging Science Node, John Statton, Kathryn Mcmahon, Rosin Mccallum, Gary Kendrick, Paul Lavery

Research outputs 2014 to 2021

The capacity of seagrasses to cope with episodes of light deprivation from overlying turbid waters may not only depend on the absolute quantity of light they receive during that episode, but also on how the light deprivation varies through time. For example, turbidity and therefore light reduction may be relatively constant over the episode or it may fluctuate depending on the frequency of pulsed turbidity events.

This report presents findings from a controlled mesocosm experiment that aimed to determine the responses of seagrasses to, and recovery from, differences in the pattern of the delivery of light. The study focussed on …


Effects Of Dredging-Related Pressures On Critical Ecological Processes For Organisms Other Than Fish Or Coral. Report Of Theme 9 - Project 9.1 Prepared For The Dredging Science Node, Jessie Short, Matthew Fraser, Dianne McLean, Gary Kendrick, Maria Byrne, Julian Caley, Doug Clarke, Andy Davis, Paul Ertemeijer, Stuart Field, Sam Gustin-Craig, John Huisman, John Keesing, Mick Keough, Paul Lavery, Ray Mansini, Kathryn McMahon, Kerrie Mergersen, Michael Rasheed, John Statton, Jim Stoddart, Paul Wu 2017 Edith Cowan University

Effects Of Dredging-Related Pressures On Critical Ecological Processes For Organisms Other Than Fish Or Coral. Report Of Theme 9 - Project 9.1 Prepared For The Dredging Science Node, Jessie Short, Matthew Fraser, Dianne Mclean, Gary Kendrick, Maria Byrne, Julian Caley, Doug Clarke, Andy Davis, Paul Ertemeijer, Stuart Field, Sam Gustin-Craig, John Huisman, John Keesing, Mick Keough, Paul Lavery, Ray Mansini, Kathryn Mcmahon, Kerrie Mergersen, Michael Rasheed, John Statton, Jim Stoddart, Paul Wu

Research outputs 2014 to 2021

This study reviewed environmental windows for organisms other than corals and fish such as sessile invertebrates, macroalgae and seagrasses. Environmental windows are periods of critical importance to the life history of a marine species, like reproduction and recruitment.

Aims

  • To review the scientific literature on the timing and spatial extent of critical ecological processes relevant to tropical WA for marine primary producers and invertebrates (i.e. organisms other than coral and finfish) and the state of knowledge regarding potential effects of dredging on these key ecological processes. The review also had a particular focus on ecological processes in marine primary producers …


Red Snapper Distribution On Natural Habitats And Artificial Structures In The Northern Gulf Of Mexico, Mandy Karnauskas, John F. Walter III, Matthew D. Campbell, Adam G. Pollack, J. Marcus Drymon, Sean P. Powers 2017 National Oceanic and Atmospheric Administration

Red Snapper Distribution On Natural Habitats And Artificial Structures In The Northern Gulf Of Mexico, Mandy Karnauskas, John F. Walter Iii, Matthew D. Campbell, Adam G. Pollack, J. Marcus Drymon, Sean P. Powers

University Faculty and Staff Publications

In 2011, an intensive, multiple-gear, fishery-independent survey was carried out in the northern Gulf of Mexico (GOM) to collect comprehensive age and length information on Red Snapper Lutjanus campechanus. Based on this synoptic survey, we produced a spatial map of Red Snapper relative abundance that integrates both gear selectivity effects and ontogenetically varying habitat usage. Our methodology generated a spatial map of Red Snapper at a 10-km2 grid resolution that is consistent with existing knowledge of the species: Red Snapper occurred in relatively high abundances at depths of 50–90 m along the coasts of Texas and Louisiana and in smaller, …


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