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Articles 2851 - 2880 of 3959
Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology
Site-Dependent Differences In Artificial Reef Function: Implications For Coral Reef Restoration, Robin L. Sherman, David S. Gilliam, Richard E. Spieler
Site-Dependent Differences In Artificial Reef Function: Implications For Coral Reef Restoration, Robin L. Sherman, David S. Gilliam, Richard E. Spieler
Marine & Environmental Sciences Faculty Articles
There is an increasing use of artificial structure in coral reef restoration (for references, see Spieler et al., this volume). Often artificial reef structures are chosen for a restoration project simply because they were used elsewhere. However, it is questionable whether the results obtained at one restoration site can be extrapolated to another. In recent years, several studies have examined the effect of artificial reef site selection on formation of associated fish, algae, and/or invertebrate assemblages (Alevizon et al., 1985; Blinova et al., 1994; Bombace et al., 1994; Caley and St. John, 1996; Chang, 1985; Haughton and Aiken, 1989; Hixon …
Artificial Substrate And Coral Reef Restoration: What Do We Need To Know To Know What We Need, Richard E. Spieler, David S. Gilliam, Robin L. Sherman
Artificial Substrate And Coral Reef Restoration: What Do We Need To Know To Know What We Need, Richard E. Spieler, David S. Gilliam, Robin L. Sherman
Marine & Environmental Sciences Faculty Articles
To use artificial substrate effectively in coral reef restoration certain basic knowledge is required: (1) what is the artificial substrate expected to accomplish relative to the goals of the restoration effort and (2) what are the expected interactions of the selected substrate’s composition, texture, orientation, and design with the damaged environment and the biota of interest. Whereas the first point is usually clear, at least in general terms, the second is not. In this review, we examine: the functions of artificial substrate in restoration and some of the physical (i.e., composition; surface texture; color and chemistry; and design in terms …
Mapping And Monitoring Of Coral Communities And Their Spatial Patterns Using A Surface-Based Video Method From A Vessel, Bernhard Riegl, Jan L. Korrubel, Charles Martin
Mapping And Monitoring Of Coral Communities And Their Spatial Patterns Using A Surface-Based Video Method From A Vessel, Bernhard Riegl, Jan L. Korrubel, Charles Martin
Marine & Environmental Sciences Faculty Articles
No Abstract Provided.
Degradation Of Reef Structure, Coral And Fish Communities In The Red Sea By Ship Groundings And Dynamite Fisheries, Bernhard Riegl
Degradation Of Reef Structure, Coral And Fish Communities In The Red Sea By Ship Groundings And Dynamite Fisheries, Bernhard Riegl
Marine & Environmental Sciences Faculty Articles
Reef degradation was investigated on 66 Egyptian Red Sea reefs—60 reefs for dynamite damage (using line transects) and six ship grounding sites (using 1 m sample squares). Ship groundings and dynamite fishing caused similar damage, reduction of the reef to rubble (65% of reefs were dynamited, mostly leeward, 58%). Changes in coral (line transect study) and fish communities (point count study) in impacted sites were documented. On impacted reefs, coral cover decreased, bare substratum and rubble increased, and fish dominance shifted away from Pomacentridae. Oceanographic conditions result in a stable pattern of coral communities (windward Acropora, leeward Porites). …
Biological Survey Report For The Calypso Natural Gas Pipeline: Shore Approach Route North Of Port Everglades Entrance Channel With Landing South Of Port Everglades Entrance Channel, Richard E. Dodge, Susan L. Thornton, David S. Gilliam, Richard Shaul
Biological Survey Report For The Calypso Natural Gas Pipeline: Shore Approach Route North Of Port Everglades Entrance Channel With Landing South Of Port Everglades Entrance Channel, Richard E. Dodge, Susan L. Thornton, David S. Gilliam, Richard Shaul
Marine & Environmental Sciences Faculty Reports
The Calypso Natural Gas Pipeline Project (project) will include a 24-inch pipeline which will extend from the Exclusive Economic Zone (EEZ) off the southeast Florida coastline to a shore approach at Port Everglades in Fort Lauderdale, Florida.
This report, which was commissioned in May 2001 and completed in July, 2001, documents the results of a detailed biological survey of underwater marine habitats from 5 to 200 feet water depth for the pipeline route. The route, which was established based on the subsea survey that was completed in May 2001 by Williamson & Associates, Inc., includes a shore approach from the …
Responses Of Three Coral Communities To The 1997–98 El Niño–Southern Oscillation: Galápagos Islands, Ecuador, Joshua S. Feingold
Responses Of Three Coral Communities To The 1997–98 El Niño–Southern Oscillation: Galápagos Islands, Ecuador, Joshua S. Feingold
Marine & Environmental Sciences Faculty Articles
One deep (13–15 m depth) and two shallow water (1.5 and 7 m) coral communities in the Galápagos Islands, Ecuador were monitored for tissue response (bleaching, paling, morbidity) and secondary responses during and after elevated temperature stress associated with the 1997–98 El Niño–Southern Oscillation (ENSO) event. Between March and May 1998, the fungiid coral Diaseris distorta paled and bleached (up to 88.0% of all individuals bleached) at 13–15 m depth. The small branching colonial coral, Psammocora stellata, paled (79.2% of all colonies) with very little bleaching (11.1%), also at 13–15 m depth. However, by May 1998 colonies of this …
Trichodesmium Spp.: Numerical Studies Of Resource Competition, Carbohydrate Ballasting, And Remote-Sensing Reflectance, Tonya Denise Clayton
Trichodesmium Spp.: Numerical Studies Of Resource Competition, Carbohydrate Ballasting, And Remote-Sensing Reflectance, Tonya Denise Clayton
OES Theses and Dissertations
In recent years, a new appreciation for the role of diazotrophy in the oceans has emerged. This dissertation reports on three modeling studies designed to investigate ecological processes associated with Trichodesmium spp., the most conspicuous marine diazotroph: (1) characterization of a generalized model Trichodesmium and issues of macronutrient resource competition; (2) carbohydrate ballasting by Trchodesmium and implications for the formation of surface accumulations; and (3) the vertical distribution of Trichodesmium and implications for detection from space.
The first study focuses on issues of nitrogen and phosphorus competition and ecosystem structure. It utilizes a simple ecosystem model that includes dissolved nitrogen …
Water Rights As Contested Terrain: The Case Of Tenmile Creek, Oregon, Marcie L. Allen
Water Rights As Contested Terrain: The Case Of Tenmile Creek, Oregon, Marcie L. Allen
Dissertations and Theses
This thesis examines the complex conflict over water rights at Tenmile Creek, located along the south central Oregon Coast. The research is an exploratory case study identifying the main motivations of actors, the constraints they faced, and the conditions that encouraged or dissuaded collaborative behavior.
The main objectives are (1) to refine the understanding of the relationship between societies and their physical environment in market societies that are both motivated to exploit and preserve natural resources and, (2) to explore the kinds of institutional arrangements that may be required to manage the water supply in a collaborative and sustainable manner. …
Groundwater Study Of The Pingelly Townsite, Edward K. Crossley
Groundwater Study Of The Pingelly Townsite, Edward K. Crossley
Resource management technical reports
A groundwater study was carried out in the townsite of Pingelly, Western Australia. It aimed to accelerate the implementation of effective salinity management options. The study consisted of a drilling investigation, expansion of a piezometer network, groundwater flow modelling and a flood risk analysis.
Groundwater Study Of The Piawaning Townsite, Russell John Speed, Ali S. Mahtab
Groundwater Study Of The Piawaning Townsite, Russell John Speed, Ali S. Mahtab
Resource management technical reports
A groundwater study was carried out in and around the townsite of Piawaning. It aimed to accelerate the implementation of effective salinity management options. The study consisted of a drilling investigation, expansion of a piezometer network, a pumping test and a flood risk analysis.
Spring/Summer 2001, Nsu Oceanographic Center
Trophic Cascades, Nutrients, And Lake Productivity: Whole-Lake Experiments, Stephen R. Carpenter, Jonathan J. Cole, James R. Hodgson, James F. Kitchell, Michael L. Pace, Darren Bade, Kathryn L. Cottingham
Trophic Cascades, Nutrients, And Lake Productivity: Whole-Lake Experiments, Stephen R. Carpenter, Jonathan J. Cole, James R. Hodgson, James F. Kitchell, Michael L. Pace, Darren Bade, Kathryn L. Cottingham
Dartmouth Scholarship
Responses of zooplankton, pelagic primary producers, planktonic bacteria, and CO2 exchange with the atmosphere were measured in four lakes with contrasting food webs under a range of nutrient enrichments during a seven-year period. Prior to enrichment, food webs were manipulated to create contrasts between piscivore dominance and planktivore dominance. Nutrient enrichments of inorganic nitrogen and phosphorus exhibited ratios of N:P > 17:1, by atoms, to maintain P limitation. An unmanipulated reference lake, Paul Lake, revealed baseline variability but showed no trends that could confound the interpretation of changes in the nearby manipulated lakes. Herbivorous zooplankton of West Long Lake (piscivorous fishes) …
Marine Biological Monitoring In Broward County, Florida: Year 1 Annual Report, David S. Gilliam, Richard E. Dodge, Richard E. Spieler, Susan L. Thornton, Lance K. B. Jordan
Marine Biological Monitoring In Broward County, Florida: Year 1 Annual Report, David S. Gilliam, Richard E. Dodge, Richard E. Spieler, Susan L. Thornton, Lance K. B. Jordan
Marine & Environmental Sciences Faculty Reports
No abstract provided.
A Comparison Of Phytoplankton Communities In Lake Prince And The Western Branch Reservoir, Suffolk, Virginia, Cara Marie Muscio
A Comparison Of Phytoplankton Communities In Lake Prince And The Western Branch Reservoir, Suffolk, Virginia, Cara Marie Muscio
Biological Sciences Theses & Dissertations
Lake Prince and the Western Branch Reservoir are two eutrophic bodies of water located in Suffolk, Virginia. Lake Prince and its two small tributaries join the Western branch via a constructed spillway. This lake system is a source of water for the surrounding municipalities, and a recreational area for community citizens. In the past, these bodies of water had repeated incidents of low oxygen and nuisance algal blooms, particularly cyanobacteria species. As a result aerators have been installed in the main body of both Lake Prince and the Western Branch Reservoir. In addition, a pipeline has been installed from North …
Ice Storm Damage To Virginia Coastal Plain Forests During The Christmas 1998 Ice Storm, Peter Elstner, Stewart Ware
Ice Storm Damage To Virginia Coastal Plain Forests During The Christmas 1998 Ice Storm, Peter Elstner, Stewart Ware
Virginia Journal of Science
On December 23-25, 1998, a major ice storm struck southeastern Virginia. The storm-deposited glaze ice felled trees and limbs, causing a power outage and highway blockage. Between February and April, 1999, we recorded occurrence, severity, and type of damage to trees over 2.5 cm dbh in nine mostly gently sloping plots in Matoaka Woods at the College of William and Mary. Frequency and severity of damage varied with species and with size of trees. Canopy damage occurred in 75% of large Fagus grandifolia trees, but in only 6% of small Sassafras albidum stems. As a group, small (2.5 to 15 …
Trachelomonas Spp. And Other Euglenophyceae Taxa In A Southeastern Virginia Lake, Harold G. Marshall
Trachelomonas Spp. And Other Euglenophyceae Taxa In A Southeastern Virginia Lake, Harold G. Marshall
Virginia Journal of Science
Trachelomonas species from Lake Kilby, a reservoir lake in southeastern Virginia are described with supportive electron micrographs. The most abundant Trachelomonas species wereT. hispida and T. volvocina. Other members of the Euglenophyceae occurring in this lake are identified.
The Implications Of The Target-Area Hypothesis On The Population Dynamics Of The Spotted Spiny Lobster, Panulirus Guttatus, Denice N. Robertson
The Implications Of The Target-Area Hypothesis On The Population Dynamics Of The Spotted Spiny Lobster, Panulirus Guttatus, Denice N. Robertson
Biological Sciences Theses & Dissertations
The target-area hypothesis, based on the theory of island biogeography, predicts that larger islands are more effective at intercepting passive immigrants. Most marine invertebrates have meroplanktonic larvae and open population dynamics, so immigration to populations in isolated benthic habitats is primarily by pelagic larval recruits. Thus, recruitment to isolated habitat “islands” may be more continuous and predictable on large islands than on small ones. Consequently, populations on large islands should not only be larger than those on small islands, but should also have more evenly distributed size structures. These differences in size structure among populations in isolated habitats of differing …
An Approach To Parameterization Of The Oceanic Turbulent Boundary Layer In The Western Pacific Warm Pool, Alexander Soloviev, Roger Lukas, Peter Hacker
An Approach To Parameterization Of The Oceanic Turbulent Boundary Layer In The Western Pacific Warm Pool, Alexander Soloviev, Roger Lukas, Peter Hacker
Marine & Environmental Sciences Faculty Articles
Vertical profiles of zonal velocity and the dissipation rate ε of the turbulent kinetic energy obtained during the Tropical Ocean-Global Atmosphere Coupled Ocean-Atmosphere Response Experiment (COARE) are analyzed in the context of planetary boundary layer relationships previously derived from atmospheric measurements. The presence of a barrier layer and the striking effect of increased dimensionless shear and ε at the bottom of the surface mixed layer of the ocean, features often observed in the western Pacific warm pool area, are consistent with the boundary layer laws. The gradient Richardson number Ri is found to be a convenient parameter for scaling the …
Review Of The Marine Mammals Of The Gulf Of Mexico, Edward O. Keith
Review Of The Marine Mammals Of The Gulf Of Mexico, Edward O. Keith
Marine & Environmental Sciences Faculty Articles
No abstract provided.
Groundwater Study Of The Bencubbin Townsite, Cahit Yesertener, P Lacey, Shawan Dogramaci, F Lewis, Department Of Agriculture, Western Australia. Rural Towns Program, Ali S. Mahtab, S Sharafi
Groundwater Study Of The Bencubbin Townsite, Cahit Yesertener, P Lacey, Shawan Dogramaci, F Lewis, Department Of Agriculture, Western Australia. Rural Towns Program, Ali S. Mahtab, S Sharafi
Resource management technical reports
A groundwater study of the townsite of Bencubbin. It aimed to accelerate the implementation of effective salinity management options. The study consisted of drilling investation and installation of a piezometer network, groundwater flow modelling and a flood risk analysis.
Groundwater Study Of The Pingrup Townsite, D Pollock, Department Of Agriculture, Western Australia, Louise Hopgood, F Lewis, Ali S. Mahtab, Anthony D. Barr, Muhammad J. Siddiqi, Ron Colman
Groundwater Study Of The Pingrup Townsite, D Pollock, Department Of Agriculture, Western Australia, Louise Hopgood, F Lewis, Ali S. Mahtab, Anthony D. Barr, Muhammad J. Siddiqi, Ron Colman
Resource management technical reports
A groundwater study was carried out in the townsite of Pingrup. It aimed to accelerate the implementation of effective salinity risk management. The study consisted of a drilling investigation and expansion of a piezometer network, a pumping test, groundwater flow modelling and a flood risk analysis.
Gross Brain Morphology In The Yellow Stingray, Urobatis Jamaicensis, Brian K. Walker, Robin L. Sherman
Gross Brain Morphology In The Yellow Stingray, Urobatis Jamaicensis, Brian K. Walker, Robin L. Sherman
Marine & Environmental Sciences Faculty Articles
The yellow stingray, Urobatis jamaicensis (family Urolophidae), a short-lived, relatively small elasmobranch species (35--40 cm total length), is a common inhabitant of hard bottom and coral reef communities in southeastern Florida and many parts of the Caribbean. A paucity of published studies deal with the yellow stingray, none however on the gross morphology of its nervous system. The gross brain structure of the yellow stingray is compared with previously published studies on other batoid elasmobranchs. The external brain structure of Urobatis jamaicensis was similar to that reported for other Dasyatids, including presence of an asymmetric cerebellum. The bilaterally symmetric brain …
Sea Turtle Conservation Program, Broward County, Fl 2001 Report, Curtis M. Burney, Stefanie Ouellette
Sea Turtle Conservation Program, Broward County, Fl 2001 Report, Curtis M. Burney, Stefanie Ouellette
Marine & Environmental Sciences Faculty Reports
No abstract provided.
Abundance And Distribution Of Commensal Amphipods From Common Marine Sponges Of Southeast Florida, Stacie E. Crowe
Abundance And Distribution Of Commensal Amphipods From Common Marine Sponges Of Southeast Florida, Stacie E. Crowe
HCNSO Student Theses and Dissertations
Marine sponges were examined from shallow waters of southeast Florida and the Florida Keys to determine species composition and distribution of commensal amphipod crustaceans from shallow reef, mangrove, and seagrass habitats. Twenty sponge species were investigated during this study, sixteen of which housed amphipods in the families Colomastigidae and/or Leucothoidae. Six species of commensal amphipods were identified. Leucothoe spinicarpa (Abildgaard) species "complex" was the most dominant amphipod commensal, representing 63% of the total amphipods collected. The L. spinicarpa "complex" contains four local morphotypes, which are diagnosed and briefly described. Common sponge hosts included Callyspongia vaginalis, Mycale sp., and Myriastra kallitetilla.
Yield-Per-Recruit Analysis For Black Drum, Pogonias Cromis, Along The East Coast Of The United States And Management Strategies For Chesapeake Bay, Cynthia M. Jones, Brian K. Wells
Yield-Per-Recruit Analysis For Black Drum, Pogonias Cromis, Along The East Coast Of The United States And Management Strategies For Chesapeake Bay, Cynthia M. Jones, Brian K. Wells
OES Faculty Publications
Black drum, Pogonias cromis along the U.S. East Coast is subject to commercial and recreational harvest. However, prior to this study no modeling had been undertaken to examine the potential for overfishing in the Chesapeake Bay region. We present evidence from yield-per-recruit models that growth overfishing of black drum is unlikely under current fishing practices in this region. Particular attention was given to fishing practices in the Chesapeake Bay region where old, large fish predominate in the commercial and recreational catches (mean age=26 years: mean total length=108.4 cm; mean weight 22.1 kg). Yield-per-recruit model results showed that growth overfishing was …
Uptake Of Dissolved Organic Selenides By Marine Phytoplankton, Stephen B. Baines, Nicholas S. Fisher, Martina A. Doblin, Gregory A. Cutter
Uptake Of Dissolved Organic Selenides By Marine Phytoplankton, Stephen B. Baines, Nicholas S. Fisher, Martina A. Doblin, Gregory A. Cutter
OES Faculty Publications
Se is present in multiple oxidation states in nature, each of which has unique chemical and biological reactivities. As a consequence, the rate of Se incorporation into food webs or its role as either a limiting nutrient or a toxic substance is a function of complex biogeochemistry. In particular, little is understood about the accumulation of dissolved organic selenides by phyto- or bacterioplankton. We assessed the bioavailability of dissolved organic selenides to marine and estuarine phytoplankton by presenting various algal species with filtered lysates of the diatom, Thalassiosira pseudonana, grown on media amended with radiolabeled selenite (75Se[IV]). …
Control Of Phytoplankton Growth By Iron Supply And Irradiance In The Subantarctic Southern Ocean: Experimental Results From The Saz Project, P. W. Boyd, A. C. Crossley, G. R. Ditullio, F. B. Griffiths, D. A. Hutchins, B. Queguiner, Peter N. Sedwick, T. W. Trull
Control Of Phytoplankton Growth By Iron Supply And Irradiance In The Subantarctic Southern Ocean: Experimental Results From The Saz Project, P. W. Boyd, A. C. Crossley, G. R. Ditullio, F. B. Griffiths, D. A. Hutchins, B. Queguiner, Peter N. Sedwick, T. W. Trull
OES Faculty Publications
The influence of irradiance and Fe supply on phytoplankton processes was studied, north (47°S, 142°E) and south (54°S, 142°E) of the Subantarctic Front in austral autumn (March 1998). At both sites, resident cells exhibited nutrient stress (Fv/Fm 0 at 47°S and 9% I0 at 54°S because of MLDs of 40 (47°S) and 90 m (54°S), when these stations were occupied. The greater MLD at 54°S is reflected by tenfold higher cellular chlorophyll a levels in the resident phytoplankton. In the 47°S experiment, chlorophyll a levels increased to >1 μg/L-1 only in the high-Fe treatments, regardless …
Control Of Phytoplankton Growth By Iron And Silicic Acid Availability In The Subantarctic Ocean: Experimental Results From The Saz Project, D. A. Hutchins, Peter N. Sedwick, G. R. Ditullio, P. W. Boyd, B. Queguiner, F. B. Griffiths, C. Crossley
Control Of Phytoplankton Growth By Iron And Silicic Acid Availability In The Subantarctic Ocean: Experimental Results From The Saz Project, D. A. Hutchins, Peter N. Sedwick, G. R. Ditullio, P. W. Boyd, B. Queguiner, F. B. Griffiths, C. Crossley
OES Faculty Publications
Subantarctic Southern Ocean surface waters in the austral summer and autumn are characterized by high concentrations of nitrate and phosphate but low concentrations of dissolved iron (Fe, similar to0.05 nM) and silicic acid (Si, <1 muM). During the Subantarctic Zone AU9706 cruise in March 1998 we investigated the relative importance of Fe and Si in controlling phytoplankton growth and species composition at a station within the subantarctic water mass (46.8degreesS, 142degreesE) using shipboard bottle incubation experiments. Treatments included unamended controls; 1.9 nM added iron (+Fe); 9 muM added silicic acid (+Si); and 1.9 nM addediron plus 9 muM added silicic acid (+Fe+Si). We followed a detailed set of biological and biogeochemical parameters over 8 days. Fe added alone clearly increased community growth rates and nitrate drawdown and altered algal community composition relative to control treatments. Surprisingly, small, lightly silicified pennate diatoms grew when Fe was added either with or without Si, despite the extremely low ambient silicic acid concentrations. Pigment analyses suggest that lightly silicified chrysophytes (type 4 haptophytes) may have preferentially responded to Si added either with or without Fe. However, for many of the parameters measured the +Fe+Si treatments showed large increases relative to both the +Fe and +Si treatments. Our results suggest that iron is the proximate limiting nutrient for chlorophyll production, photosynthetic efficiency, nitrate drawdown, and diatom growth, but that Si also exerts considerable control over algal growth and species composition. Both nutrients together are needed to elicit a maximum growth response, suggesting that both Fe and Si play important roles in structuring the subantarctic phytoplankton community.
Holocene Sediment Records From The Continental Shelf Of Mac. Robertson Land, East Antarctica, Peter N. Sedwick, Peter T. Harris, Lisette G. Robertson, Gary M. Mcmurtry, Maximilian D. Cremer, Philip Robinson
Holocene Sediment Records From The Continental Shelf Of Mac. Robertson Land, East Antarctica, Peter N. Sedwick, Peter T. Harris, Lisette G. Robertson, Gary M. Mcmurtry, Maximilian D. Cremer, Philip Robinson
OES Faculty Publications
Geochemical records are presented for five sediment cores from basins on the continental shelf of Mac. Robertson Land, East Antarctica. The cores contain 2-4 m thick sequences of hemipelagic, siliceous mud and ooze (SMO) deposited under seasonally open marine conditions. The inner and middle shelf SMO sequences are massive dark olive green material, whereas the outer shelf SMO sequences are dark olive material interspersed with light olive green layers similar to1-10 cm thick. The biogenic material is dominated by marine diatoms including Fragilariopsis curta, Fragilariopsis cylindrus, and Chaetoceros spp. in the dark-colored SMO and Corethron criophilum in the …
Hydrogeological Characterization Of The South Oyster Bacterial Transport Site Using Geophysical Data, Susan S. Hubbard, Jinsong Chen, John Peterson, Ernest L. Majer, Kenneth H. Williams, Donald J. Swift, Brian Mailloux, Yoram Rubin
Hydrogeological Characterization Of The South Oyster Bacterial Transport Site Using Geophysical Data, Susan S. Hubbard, Jinsong Chen, John Peterson, Ernest L. Majer, Kenneth H. Williams, Donald J. Swift, Brian Mailloux, Yoram Rubin
OES Faculty Publications
A multidisciplinary research team has conducted a field-scale bacterial transport study within an uncontaminated sandy Pleistocene aquifer near Oyster, Virginia. The overall goal of the project was to evaluate the importance of heterogeneities in controlling the field-scale transport of bacteria that are injected into the ground for remediation purposes. Geochemical, hydrological, geological, and geophysical data were collected to characterize the site prior to conducting chemical and bacterial injection experiments. In this paper we focus on results of a hydrogeological characterization effort using geophysical data collected across a range of spatial scales. The geophysical data employed include surface ground-penetrating radar, radar …