Literature Library

Currently indexing 10051 titles

Is monitoring for mass spawning events in coral assemblages in north Western Australia likely to detect spawning?

Citation Information: Marine Pollution Bulletin; Available online 10 September 2012; In Press, Corrected Proof

Authors: Craig A. Styan, Natalie L. Rosser

Abstract: In north Western Australia coral reefs occur near ports being developed to support rapidly expanding resources industries. Dredging for port construction is required to stop during significant mass coral spawning events due to the sensitivity of gametes and larvae to increases in turbidity and sedimentation, but the timing of this event can vary between seasons and years so monitoring is used to predict when spawning is imminent. Here we used simulations to mimick sampling strategies currently used in some coral spawning monitoring programmes in Western Australia, to assess the ability of these programmes to be able to predict multi-specific mass spawning events. We found that current practices may sometimes miss spawning events that are likely to be considered large enough to warrant stopping dredging. Generally, sampling fewer individuals in a large number of species is a better way of monitoring for upcoming spawning than sampling a large number of individuals in a small number of species, but overall, greater sampling efforts than are currently undertaken are needed if moderately sized events are to be detected reliably. Determining exactly how many samples are needed, however, depends on having a clearer definition of what actually constitutes a “significant mass spawning” event in the first place.

Filament formation and evolution in buoyant coastal waters: observation and modelling

Citation Information: Progress in Oceanography; Available online 11 September 2012; In Press, Accepted Manuscript

Authors: Ilaria Iermano, Giovanni Liguori, Daniele Iudicone, Bruno Buongiorno Nardelli, Simone Colella, Adriana Zingone, Vincenzo Saggiomo, Maurizio Ribera d’Alcalà

Abstract: This paper presents a detailed analysis of the formation and subsequent evolution of filament-like structures observed in a relatively small area of the mid-Tyrrhenian Sea (Mediterranean Sea). The filament dynamics and potential impact on the cross-shelf exchange budget are investigated based on a combined use of remote sensing imagery, in-situ data and numerical modelling.

The complexity of these phenomena is shown by focusing on four distinct events that led to cross-shelf transport, each representative of a different dynamic process and a distinct expected impact on the coastal area. A systematic analysis of available observations for the years 1998-2006 underlines the role of the interplay of atmospheric freshwater fluxes, river loads and wind stress variations, which may create favourable conditions for the convergence of shelf waters (particularly at coastal capes) and the subsequent formation of short-lived filaments along the coast.

The response of the buoyant coastal waters to periods of wind reversal and fluctuating freshwater discharge rates is examined through idealised Regional Ocean Modeling System (ROMS) simulations. The filaments observed in remote sensing imagery were well reproduced by the numerical exercise, where the filaments appear as organised sub-mesoscale structures that possess high relative vorticity and develop at the river mouths or adjacent capes. In both scenarios, the filaments appear largely determined by i) the presence of a buoyancy anomaly, ii) the angle between the wind pulse direction and the coast and iii) irregularities in the coastal profile.

The ensemble of results suggests that the occurrence of such transient, intense structures may contribute considerably to the biological variability and cross-shelf exchange in coastal areas with similar traits.

A National Perspective on the Role of Marine Protected Areas in Sustaining Fisheries

Citation Information: Fisheries Research, Volume 144, July 2013, Pages 23–27

Authors: Lauren Wenzel, Jordan Gass, Mimi D’Iorio, Jason Blackburn

Abstract: Marine Protected Areas (MPAs) have been used by traditional cultures for generations as a means to sustain local fisheries for food security. In more recent decades, MPAs have been used by coastal and ocean managers to protect special areas for a wide range of purposes–protecting threatened or rare species, conserving areas for biological diversity and other ecological functions, setting aside areas for recreation–as well as a fisheries management tool. While the role of an MPA in protecting species or biological diversity is fairly well understood, their role as fisheries management tools is more complex and controversial. This paper provides an overview of the use of MPAs as a fisheries management tool in the United States, drawing on the comprehensive MPA Inventory developed and maintained by the National Marine Protected Areas Center (MPA Center).

Organic coasts? Regulatory challenges of certifying integrated shrimp–mangrove production systems in Vietnam

Citation Information: Journal of Rural Studies; Available online 15 September 2012; In Press, Corrected Proof

Authors: Tran Thi Thu Ha, Simon R. Bush, Arthur P.J. Mol, Han van Dijk

Abstract: The Vietnamese government aims to expand the scale of Naturland certified organic production in integrated shrimp–mangrove farming systems across the coast of Ca Mau province by 2015. In doing so the division between public and private regulation has become blurred. We analyze the government's goal by examining the regulatory challenges of using organic certification as a means of linking farm-level management to the sustainability of coastal (mangrove) landscapes. The results show the importance of farmer perceptions of sustainable farm and landscape management, fair benefit sharing mechanisms in the certified value chain, and legitimate private sector-led auditing. We conclude that in order to overcome conflicts of interest and legitimate representation in organic certification, the social and economic conditions of production require regulatory intervention from provincial and local level government. To achieve benefits beyond the scale of the farm, the role of shrimp producers should be redefined as partners in rather than targets of regulation.

A modeling approach toward oil spill management along the Eastern Mediterranean

Citation Information: Journal of Environmental Management; Volume 113, 30 December 2012, Pages 93–102

Authors: M. El-Fadel, R. Abdallah, G. Rachid

Abstract: This paper examines the temporal and spatial distributions of the largest oil spill along the Eastern Mediterranean and explores management options (boom deployment and fuel upgrade) to reduce potential adverse impacts on the marine environment from similar accidents. For this purpose, the trajectory and weathering of the ∼18,000 tons of heavy fuel oil spilled from the Jiyeh thermal power plant were simulated along the coast of Lebanon using the 3D MEDSLIK model, supported with sea water sampling and analysis and field measurements. The base simulation of the spill under existing conditions at the time of occurrence defined the temporal distribution over 90 days of oil spilled in terms of percentage of oil on the surface or evaporated (13.1%), dispersed in the water column or landed on the coast (86.9% landed of which 30.1% were potentially releasable). The spatial distribution defined shoreline stretches with high risk of exposure (located 35 km north of the source and stretching for more than 150 km with medium to low risk exposure). Parametric analysis revealed a relatively higher sensitivity to the drift factor, the current depth, and the time of spill parameters. Deployment of booms reduced shorelines exposure by ∼95% in comparison to baseline conditions, and medium or light brands increased evaporation by ∼22–42% and reduced oil reaching the coast by ∼37–57% in comparison to heavy fuel oil.

Novel offshore application of photovoltaics in comparison to conventional marine renewable energy technologies

Citation Information: Renewable Energy; Volume 50, February 2013, Pages 879–888

Authors: Kim Trapani, Dean L. Millar, Helen C.M. Smith

Abstract: An original proposal for the deployment of photovoltaic (PV) systems in offshore environments is presented in this paper. Crystalline PV panels are considered where they are deployed on pontoon type structures and there are six case study examples precedent practise of such deployments in lakes and reservoirs (but not seas). The authors put forward an alternative based on flexible thin film PV that floats directly on the waterline. The paper then concentrates on the techno-economic appraisal of offshore PV systems in comparison to conventional marine renewable energy technologies. The difficulties of comparing offshore technology projects developed in various countries, using different currencies and in different years are overcome so that such comparisons are made on an equitable basis. The discounted cost of electricity generated by each scheme is determined, including capital expenditure (CAPEX) and yearly operation and maintenance (O&M) costs.

Actual wind, tidal (current turbines and barrages) and wave projects were considered in the analysis alongside crystalline and thin film PV. Thin film PV was found to be economically competitive with offshore wind energy projects for latitudes ranging from 45°N to 45°S. The specific yield, assessed in terms of GWh/km2 was higher for thin film PV than for wind, wave and tidal barrage systems. In addition the specific installed capacity, expressed in MW/km2 was also higher than the other conventional technologies considered (excluding tidal current turbines).

Assessing Coral Reefs on a Pacific-Wide Scale Using the Microbialization Score

Citation Information: McDole T, Nulton J, Barott KL, Felts B, Hand C, et al. (2012) Assessing Coral Reefs on a Pacific-Wide Scale Using the Microbialization Score. PLoS ONE 7(9): e43233. doi:10.1371/journal.pone.0043233

Abstract: The majority of the world's coral reefs are in various stages of decline. While a suite of disturbances (overfishing, eutrophication, and global climate change) have been identified, the mechanism(s) of reef system decline remain elusive. Increased microbial and viral loading with higher percentages of opportunistic and specific microbial pathogens have been identified as potentially unifying features of coral reefs in decline. Due to their relative size and high per cell activity, a small change in microbial biomass may signal a large reallocation of available energy in an ecosystem; that is the microbialization of the coral reef. Our hypothesis was that human activities alter the energy budget of the reef system, specifically by altering the allocation of metabolic energy between microbes and macrobes. To determine if this is occurring on a regional scale, we calculated the basal metabolic rates for the fish and microbial communities at 99 sites on twenty-nine coral islands throughout the Pacific Ocean using previously established scaling relationships. From these metabolic rate predictions, we derived a new metric for assessing and comparing reef health called the microbialization score. The microbialization score represents the percentage of the combined fish and microbial predicted metabolic rate that is microbial. Our results demonstrate a strong positive correlation between reef microbialization scores and human impact. In contrast, microbialization scores did not significantly correlate with ocean net primary production, local chla concentrations, or the combined metabolic rate of the fish and microbial communities. These findings support the hypothesis that human activities are shifting energy to the microbes, at the expense of the macrobes. Regardless of oceanographic context, the microbialization score is a powerful metric for assessing the level of human impact a reef system is experiencing.

Controlling Effects of Irradiance and Heterotrophy on Carbon Translocation in the Temperate Coral Cladocora caespitosa

Citation Information: Tremblay P, Ferrier-Pagès C, Maguer JF, Rottier C, Legendre L, et al. (2012) Controlling Effects of Irradiance and Heterotrophy on Carbon Translocation in the Temperate Coral Cladocora caespitosa. PLoS ONE 7(9): e44672. doi:10.1371/journal.pone.0044672

Abstract: Temperate symbiotic corals, such as the Mediterranean species Cladocora caespitosa, live in seasonally changing environments, where irradiance can be ten times higher in summer than winter. These corals shift from autotrophy in summer to heterotrophy in winter in response to light limitation of the symbiont’s photosynthesis. In this study, we determined the autotrophic carbon budget under different conditions of irradiance (20 and 120 µmol photons m−2 s−1) and feeding (fed three times a week with Artemia salina nauplii, and unfed). Corals were incubated in H13CO3-enriched seawater, and the fate of 13C was followed in the symbionts and the host tissue. The total amount of carbon fixed by photosynthesis and translocated was significantly higher at high than low irradiance (ca. 13 versus 2.5–4.5 µg cm−2 h−1), because the rates of photosynthesis and carbon fixation were also higher. However, the percent of carbon translocation was similar under the two irradiances, and reached more than 70% of the total fixed carbon. Host feeding induced a decrease in the percentage of carbon translocated under low irradiance (from 70 to 53%), and also a decrease in the rates of carbon translocation per symbiont cell under both irradiances. The fate of autotrophic and heterotrophic carbon differed according to irradiance. At low irradiance, autotrophic carbon was mostly respired by the host and the symbionts, and heterotrophic feeding led to an increase in host biomass. Under high irradiance, autotrophic carbon was both respired and released as particulate and dissolved organic carbon, and heterotrophic feeding led to an increase in host biomass and symbiont concentration. Overall, the maintenance of high symbiont concentration and high percentage of carbon translocation under low irradiance allow this coral species to optimize its autotrophic carbon acquisition, when irradiance conditions are not favourable to photosynthesis.

The Early Life History of the Clam Macoma balthica in a High CO2 World

Citation Information: Van Colen C, Debusschere E, Braeckman U, Van Gansbeke D, Vincx M (2012) The Early Life History of the Clam Macoma balthica in a High CO2 World. PLoS ONE 7(9): e44655. doi:10.1371/journal.pone.0044655

Abstract: This study investigated the effects of experimentally manipulated seawater carbonate chemistry on several early life history processes of the Baltic tellin (Macoma balthica), a widely distributed bivalve that plays a critical role in the functioning of many coastal habitats. We demonstrate that ocean acidification significantly depresses fertilization, embryogenesis, larval development and survival during the pelagic phase. Fertilization and the formation of a D-shaped shell during embryogenesis were severely diminished: successful fertilization was reduced by 11% at a 0.6 pH unit decrease from present (pH 8.1) conditions, while hatching success was depressed by 34 and 87%, respectively at a 0.3 and 0.6 pH unit decrease. Under acidified conditions, larvae were still able to develop a shell during the post-embryonic phase, but higher larval mortality rates indicate that fewer larvae may metamorphose and settle in an acidified ocean. The cumulative impact of decreasing seawater pH on fertilization, embryogenesis and survival to the benthic stage is estimated to reduce the number of competent settlers by 38% for a 0.3 pH unit decrease, and by 89% for a 0.6 pH unit decrease from present conditions. Additionally, slower growth rates and a delayed metamorphosis at a smaller size were indicative for larvae developed under acidified conditions. This may further decline the recruit population size due to a longer subjection to perturbations, such as predation, during the pelagic phase. In general, early life history processes were most severely compromised at ~pH 7.5, which corresponds to seawater undersaturated with respect to aragonite. Since recent models predict a comparable decrease in pH in coastal waters in the near future, this study indicates that future populations of Macoma balthica are likely to decline as a consequence of ongoing ocean acidification.

Marine Mammal Impacts in Exploited Ecosystems: Would Large Scale Culling Benefit Fisheries?

Citation Information: Morissette L, Christensen V, Pauly D (2012) Marine Mammal Impacts in Exploited Ecosystems: Would Large Scale Culling Benefit Fisheries? PLoS ONE 7(9): e43966. doi:10.1371/journal.pone.0043966

Abstract: Competition between marine mammals and fisheries for marine resources—whether real or perceived—has become a major issue for several countries and in international fora. We examined trophic interactions between marine mammals and fisheries based on a resource overlap index, using seven Ecopath models including marine mammal groups. On a global scale, most food consumed by marine mammals consisted of prey types that were not the main target of fisheries. For each ecosystem, the primary production required (PPR) to sustain marine mammals was less than half the PPR to sustain fisheries catches. We also developed an index representing the mean trophic level of marine mammal's consumption (TLQ) and compared it with the mean trophic level of fisheries' catches (TLC). Our results showed that overall TLQ was lower than TLC (2.88 versus 3.42). As fisheries increasingly exploit lower-trophic level species, the competition with marine mammals may become more important. We used mixed trophic impact analysis to evaluate indirect trophic effects of marine mammals, and in some cases found beneficial effects on some prey. Finally, we assessed the change in the trophic structure of an ecosystem after a simulated extirpation of marine mammal populations. We found that this lead to alterations in the structure of the ecosystems, and that there was no clear and direct relationship between marine mammals' predation and the potential catch by fisheries. Indeed, total biomass, with no marine mammals in the ecosystem, generally remained surprisingly similar, or even decreased for some species.

Differences in Recruitment and Life-History Strategy Alter Zooplankton Spring Dynamics Under Climate-Change Conditions

Citation Information: Ekvall MK, Hansson L-A (2012) Differences in Recruitment and Life-History Strategy Alter Zooplankton Spring Dynamics Under Climate-Change Conditions. PLoS ONE 7(9): e44614. doi:10.1371/journal.pone.0044614

Abstract: In recent decades temperature elevation has been the focus of many studies on climate change, including effects on planktonic communities, but few studies have examined the effects of increased water color ("brownification"). Since these changes are likely to occur simultaneously, it is important to investigate their potential interactive effects. Accordingly, we performed a mesocosm experiment where we combined a 3°C increase in temperature with a doubling in water color to study how these factors affect zooplankton. In particular, we looked at recruitment of cladocerans and copepods from the sediment in spring, as well as their establishment in the water column. Our results show that an elevated temperature will have considerable effects on recruitment as well as on pelagic abundances of both cladocerans and copepods, whereas increases in water color will have less effects on the recruitment and pelagic establishment. But more importantly, the proportion of cladocerans in the water column, relative to copepods, increased at higher temperature, suggesting that cladocerans benefit more from elevated temperatures than copepods do. Overall, these results likely stem from the combined effect of changes in recruitment and differences in life history between copepods and cladocerans. Taking a wider outlook, this suggests that future climate warming will change the dominance pattern of zooplankton communities in spring, and, in accordance with the experimental data, we here show that cladocerans are more abundant than copepods in natural lake ecosystems during warmer rather than cooler years.

Global Coverage of Cetacean Line-Transect Surveys: Status Quo, Data Gaps and Future Challenges

Citation Information: Kaschner K, Quick NJ, Jewell R, Williams R, Harris CM (2012) Global Coverage of Cetacean Line-Transect Surveys: Status Quo, Data Gaps and Future Challenges. PLoS ONE 7(9): e44075. doi:10.1371/journal.pone.0044075

Abstract: Knowledge of abundance, trends and distribution of cetacean populations is needed to inform marine conservation efforts, ecosystem models and spatial planning. We compiled a geo-spatial database of published data on cetacean abundance from dedicated visual line-transect surveys and encoded >1100 abundance estimates for 47 species from 430 surveys conducted worldwide from 1975–2005. Our subsequent analyses revealed large spatial, temporal and taxonomic variability and gaps in survey coverage. With the exception of Antarctic waters, survey coverage was biased toward the northern hemisphere, especially US and northern European waters. Overall, <25% of the world's ocean surface was surveyed and only 6% had been covered frequently enough (≥5 times) to allow trend estimation. Almost half the global survey effort, defined as total area (km2) covered by all survey study areas across time, was concentrated in the Eastern Tropical Pacific (ETP). Neither the number of surveys conducted nor the survey effort had increased in recent years. Across species, an average of 10% of a species' predicted range had been covered by at least one survey, but there was considerable variation among species. With the exception of three delphinid species, <1% of all species' ranges had been covered frequently enough for trend analysis. Sperm whales emerged from our analyses as a relatively data-rich species. This is a notoriously difficult species to survey visually, and we use this as an example to illustrate the challenges of using available data from line-transect surveys for the detection of trends or for spatial planning. We propose field and analytical methods to fill in data gaps to improve cetacean conservation efforts.

The Impact of Escaped Farmed Atlantic Salmon (Salmo salar L.) on Catch Statistics in Scotland

Citation Information: Green DM, Penman DJ, Migaud H, Bron JE, Taggart JB, et al. (2012) The Impact of Escaped Farmed Atlantic Salmon (Salmo salar L.) on Catch Statistics in Scotland. PLoS ONE 7(9): e43560. doi:10.1371/journal.pone.0043560

Abstract: In Scotland and elsewhere, there are concerns that escaped farmed Atlantic salmon (Salmo salar L.) may impact on wild salmon stocks. Potential detrimental effects could arise through disease spread, competition, or inter-breeding. We investigated whether there is evidence of a direct effect of recorded salmon escape events on wild stocks in Scotland using anglers' counts of caught salmon (classified as wild or farmed) and sea trout (Salmo trutta L.). This tests specifically whether documented escape events can be associated with reduced or elevated escapes detected in the catch over a five-year time window, after accounting for overall variation between areas and years. Alternate model frameworks were somewhat inconsistent, however no robust association was found between documented escape events and higher proportion of farm-origin salmon in anglers' catch, nor with overall catch size. A weak positive correlation was found between local escapes and subsequent sea trout catch. This is in the opposite direction to what would be expected if salmon escapes negatively affected wild fish numbers. Our approach specifically investigated documented escape events, contrasting with earlier studies examining potentially wider effects of salmon farming on wild catch size. This approach is more conservative, but alleviates some potential sources of confounding, which are always of concern in observational studies. Successful analysis of anglers' reports of escaped farmed salmon requires high data quality, particularly since reports of farmed salmon are a relatively rare event in the Scottish data. Therefore, as part of our analysis, we reviewed studies of potential sensitivity and specificity of determination of farmed origin. Specificity estimates are generally high in the literature, making an analysis of the form we have performed feasible.

Predator Cue and Prey Density Interactively Influence Indirect Effects on Basal Resources in Intertidal Oyster Reefs

Citation Information: Hughes AR, Rooker K, Murdock M, Kimbro DL (2012) Predator Cue and Prey Density Interactively Influence Indirect Effects on Basal Resources in Intertidal Oyster Reefs. PLoS ONE 7(9): e44839. doi:10.1371/journal.pone.0044839

Abstract: Predators can influence prey abundance and traits by direct consumption, as well as by non-consumptive effects of visual, olfactory, or tactile cues. The strength of these non-consumptive effects (NCEs) can be influenced by a variety of factors, including predator foraging mode, temporal variation in predator cues, and the density of competing prey. Testing the relative importance of these factors for determining NCEs is critical to our understanding of predator-prey interactions in a variety of settings. We addressed this knowledge gap by conducting two mesocosm experiments in a tri-trophic intertidal oyster reef food web. More specifically, we tested how a predatory fish (hardhead catfish, Ariopsis felis) directly influenced their prey (mud crabs, Panopeus spp.) and indirectly affected basal resources (juvenile oysters, Crassostrea virginica), as well as whether these direct and indirect effects changed across a density gradient of competing prey. Per capita crab foraging rates were inversely influenced by crab density, but they were not affected by water-borne predator cues. As a result, direct consumptive effects on prey foraging rates were stronger than non-consumptive effects. In contrast, predator cue and crab density interactively influenced indirect predator effects on oyster mortality in two experiments, with trait-mediated and density-mediated effects of similar magnitude operating to enhance oyster abundance. Consistent differences between a variable predator cue environment and other predator cue treatments (no cue and constant cue) suggests that an understanding of the natural risk environment experienced by prey is critical to testing and interpreting trait-mediated indirect interactions. Further, the prey response to the risk environment may be highly dependent on prey density, particularly in prey populations with strong intra-specific interactions.

Marine Spatial Planning: Current Status and Recommendations for Future Spending

Citation Information: Washington State Department of Natural Resources, Aquatic Resources Division; September 7, 2012

Authors: Jennifer Hennessey, Bridgit Trosin, Michal Rechner, Katrina Lassiter

Description: This document provides a status report on Washington state’s progress toward marine spatial planning in Washington’s marine waters. It identifies how the state is spending current state funds and describes funding needs for the 2013-2015 Biennium. The intent of this planning effort is to build upon the marine spatial component of existing statewide efforts and to improve the coordination among state agencies in developing and implementing marine management plans.

The Certainty of Confronting Uncertainty in the Chesapeake Bay Restoration Effort

Citation Information: Choices: 3rd Quarter 2011, 26(3)

Author: Carlton Hershner

Abstract: The Chesapeake Bay is a very large complex system that no longer has the capacity to provide all of the beneficial human services it once did. Restoring some of that capacity is a consensus goal for the millions of people who live in the watershed and impact its condition. The challenges of improving the condition of such a large ecosystem lie not only in assembling the necessary resources, but also in knowing what must be done and how best to do it. These questions are at the very limits of our current knowledge and so there is inherent uncertainty in all the answers. The amount of uncertainty varies from very little—identification of the system’s problem and the causes, to moderate—determination of the exact amounts of excess pollutant loads from all parts of the watershed, to significant—forecasting the performance of best management practices. Since the system will continue to degrade if nothing is done, inaction is not an option. Moving forward requires a willingness to act with less than perfect knowledge, constantly striving to reduce the uncertainty by learning and adapting as we go.

What follows is a brief review of some of the principal questions decision-makers currently confront in efforts to restore water quality conditions in the Chesapeake Bay. The answers to these questions vary significantly from “nearly certain” to “best available estimate.” Understanding this circumstance is central to both designing the strategy and setting expectations.

The Sound in the Silence: Discovering a Fish's Soundscape

Citation Information: Science 14 September 2012; Vol. 337 no. 6100 pp. 1290-1291

DOI: 10.1126/science.337.6100.1290

Author: Jane J. Lee

Abstract: Bioacoustics pioneer Arthur Popper is getting ready to retire, but his work on how fish perceive sound isn't fading away.

As an undergraduate more than 40 years ago, Arthur Popper took a detour on his way to a class on New York University's campus in the Bronx that set him on a course to become the godfather of fish hearing. Popper decided to visit a new pet shop, where he spied a fish without eyes. He began thinking about how it lived guided by its other senses. The encounter eventually led Popper, now a bioacoustician at the University of Maryland, College Park, to become one of the world's pioneers in understanding how fish perceive and respond to sound. “If I hadn't walked by that shop that day,” he says, “I'd have a different life.”

Contributions of the U.S. Integrated Ocean Observing System to National and Regional Coastal Hazards and Resources Information, Tools, and Services

Citation Information: Marine Technology Society Journal, Volume 45, Number 1, January/February 2011 , pp. 29-38(10)

Authors: Ostrander, Chris E.; Seim, Harvey; Smith, Elizabeth; Studer, Ben; Luscher-Aissauoi, Audra; Fletcher, Chip

Abstract: A changing climate, coupled with increasing development and population growth within the coastal margins of the United States, presents a growing threat to coastal populations, ecosystems, and infrastructure associated with chronic and catastrophic coastal hazards and a growing reliance on coastal resources. The U.S. Integrated Ocean Observing System (IOOS®) provides a unique capability to observe the coastal and open ocean waters of the United States and provide value-added, customized data tools, products, and services to inform decision making related to coastal hazards and resources management, assessment, and risk by individuals, resource managers, policy makers, and local agencies. Increasingly, the partnership of IOOS Regional Associations with the U.S. IOOS Program Office has the capacity to provide critical observational and scientific information needed to inform coastal planning and management efforts related to some of the most pressing problems facing our coastal zone: namely, impacts of a changing climate on coastal communities and ecosystems, sea level rise, and the competing and oftentimes conflicting uses of our coastal zone that necessitate integrated Coastal and Marine Spatial Planning. Discussed herein are three examples of regional IOOS capacity to provide information related to beach safety, coastal inundation, and marine spatial planning.

Underwater Noise Pollution From Munitions Clearance and Disposal, Possible Effects on Marine Vertebrates, and Its Mitigation

Citation Information: Marine Technology Society Journal, Volume 45, Number 6, November/December 2011 , pp. 80-88(9)

Author: Koschinski, Sven

Abstract: Underwater detonations have the potential for serious injury in marine vertebrates such as fishes, reptiles, birds and mammals. The high detonation velocity creates a shock wave. The main reason for injury is the extremely short signal rise time combined with a high overpressure. A negative pressure phase generating cavitation shortly after the peak overpressure can increase organ and tissue damage. Due to surface reflection generating a reversed phase replica of the detonation, this phenomenon is very pronounced in shallow waters. Organs most seriously affected by detonations are those with gas/tissue interfaces (e.g., ears, lungs, swim bladders, air sacs, intestines). Observed injuries include disruption of cells and tissues by differential displacement, internal bleeding, embolism, and auditory damage. Furthermore, compression of the thorax by the shock wave initiates a rapid increase in blood pressure, which can cause damage in the brain and ears. In order to protect marine life, all possible attempts should be made to avoid underwater detonations. For detonations that cannot be avoided due to safety considerations, a number of mitigation measures are presented including bubble curtains, scaring devices, visual and acoustic monitoring, and seasonal and spatial planning. However, mitigation measures have varying degrees of efficiency. Low-order detonations are not a real alternative due to the release of toxic munitions constituents to the environment. For each detonation, a proper site- and munitions-specific risk assessment and mitigation strategy must be developed.

Development of a spatially resolved linked hydrodynamic and exposure model (LOTOX2) for PCBs in Lake Ontario

Citation Information: Journal of Great Lakes Research; Volume 38, Issue 3, September 2012, Pages 490–503

Authors: Jagjit Kaur, Joseph V. DePinto, Joseph F. Atkinson, Edward Verhamme, Thomas C. Young

Abstract: A linked hydrodynamic–hydrophobic organic chemical mass balance and food chain bioaccumulation model, LOTOX2, was developed to support the Lake Ontario Lakewide Management Plan (LaMP) for establishing contaminant load reduction strategies. This paper describes the development of LOTOX2, including the linkage with a relatively finer-scale hydrodynamic model (the Princeton Ocean Model, POM). An important component of this development was the reconstruction of PCB loading history (1930–2005), which was used to understand historic trends and to conduct model calibration/confirmation for total PCBs (tPCBs) in the lake water, sediments, and adult lake trout using data for the last 25 years. A separate mass balance was conducted for the radioisotope cesium-137 (137Cs) in order to develop a sorbent mass balance model for the system. Following calibration and confirmation, a diagnostic application of the model showed that the lake is not yet at steady-state with current loads. It will take more than 50 years for tPCB concentration in lake trout to decrease to a steady-state value of about 0.4 ppm if year 2005 loads remain constant. If all external loads were instantaneously eliminated in 2005, it would take approximately 40 years for the adult lake trout tPCB concentration to reach 0.05 ppm (the uniform Great Lakes protocol value for unrestricted consumption) from its current level of 0.74 ppm.

Pages

Subscribe to OpenChannels Literature Library