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Climate change and the oceans – What does the future hold? Full text
2013
Bijma, Jelle | Pörtner, Hans-O. | Yesson, Chris | Rogers, Alex D.
Climate change and the oceans – What does the future hold? Full text
2013
Bijma, Jelle | Pörtner, Hans-O. | Yesson, Chris | Rogers, Alex D.
The ocean has been shielding the earth from the worst effects of rapid climate change by absorbing excess carbon dioxide from the atmosphere. This absorption of CO2 is driving the ocean along the pH gradient towards more acidic conditions. At the same time ocean warming is having pronounced impacts on the composition, structure and functions of marine ecosystems. Warming, freshening (in some areas) and associated stratification are driving a trend in ocean deoxygenation, which is being enhanced in parts of the coastal zone by upwelling of hypoxic deep water. The combined impact of warming, acidification and deoxygenation are already having a dramatic effect on the flora and fauna of the oceans with significant changes in distribution of populations, and decline of sensitive species. In many cases, the impacts of warming, acidification and deoxygenation are increased by the effects of other human impacts, such as pollution, eutrophication and overfishing.The interactive effects of this deadly trio mirrors similar events in the Earth’s past, which were often coupled with extinctions of major species’ groups. Here we review the observed impacts and, using past episodes in the Earth’s history, set out what the future may hold if carbon emissions and climate change are not significantly reduced with more or less immediate effect.
Show more [+] Less [-]Climate change and the oceans - What does the future hold? Full text
2013
Bijma, Jelle | Pörtner, Hans-Otto | Yesson, Chris | Rogers, A. D.
Assessing the damage caused by Deepwater Horizon: Not just another Exxon Valdez Full text
2013
Perrons, Robert K.
In light of the high stakes of the Deepwater Horizon civil trial and the important precedent-setting role that the case will have on the assessment of future marine disasters, the methodologies underpinning the calculations of damage on both sides will be subjected to considerable scrutiny. Despite the importance of the case, however, there seems to be a pronounced lack of convergence about it in the academic literature. Contributions from scientific journals frequently make comparisons to the Ixtoc I oil spill off the coast of Mexico in 1979; the legal literature, by stark contrast, seems to be much more focused on the Exxon Valdez spill that occurred off the shores of Alaska in 1989. This paper accordingly calls for a more thorough consideration of other analogs beyond the Exxon Valdez spill—most notably, the Ixtoc I incident—in arriving at an assessment of the damage caused by the Deepwater Horizon disaster.
Show more [+] Less [-]Dissolved oxygen in the rehabilitation phase of an estuary: Influence of sewage pollution abatement and hydro-climatic factors Full text
2013
Villate, Fernando | Iriarte, Arantza | Uriarte, Ibon | Intxausti, Lander | de la Sota, Alejandro
Seasonal and inter-annual variations of dissolved oxygen (DO) along the estuary of Bilbao were investigated from 1998 to 2008, during its rehabilitation phase from pollution, to determine whether anthropogenic or natural forcings or both govern DO dynamics and hypoxia. Both seasonal and inter-annual variations of DO were best explained by hydro-climatic factors, sewage pollution and phytoplankton dynamics in the inner, intermediate and outer estuary respectively. The most remarkable intra-decadal improvement in DO occurred in the halocline layer of the intermediate estuary, where the factor that best explained these changes was sewage pollution abatement. However, in the estuarine hotspot for hypoxia, i.e. inner estuary bottom waters, no parallel response to sewage pollution abatement was observed and hydro-climatic factors were the main drivers of inter-annual DO variations. Differences in the degree of stratification and flushing accounted for this differential response of DO to anthropogenic and climate-related forcings at both axial and vertical scales.
Show more [+] Less [-]Water concentrations of PAH, PCB and OCP by using semipermeable membrane devices and sediments Full text
2013
Karacık, B. | Okay, O.S. | Henkelmann, B. | Pfister, G. | Schramm, K.-W.
Water concentrations of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were estimated from semipermeable membrane devices (SPMDs) and from sediment pollutant concentrations. SPMDs were deployed in the Istanbul Strait and Marmara Sea and retrieved after 7 and 21days. Performance reference compounds (PRCs) were used to determine the site-specific sampling rates of the compounds. Water concentrations (Cw) of the analyzed compounds estimated by using two different calculation methods for SPMDs were found similar. Cw of total PAHs estimated from SPMDs (Cw-spmd) were found between 13 and 79ngL−1 and between 7.0 and 68ngL−1 for 7 and 21days of deployments respectively. Water concentrations of PCBs using sediment data was found as between 0.001 and 11.0ngL−1. The highest value of Cw-spmd for two deployments were 2.8ngL−1 for OCPs. Cw estimated from sediment concentrations were generally higher than those estimated from SPMDs.
Show more [+] Less [-]Use of skin and blubber tissues of small cetaceans to assess the trace element content of internal organs Full text
2013
Aubail, A. | Méndez-Fernandez, P. | Bustamante, P. | Churlaud, C. | Ferreira, M. | Vingada, J.V. | Caurant, F.
Use of skin and blubber tissues of small cetaceans to assess the trace element content of internal organs Full text
2013
Aubail, A. | Méndez-Fernandez, P. | Bustamante, P. | Churlaud, C. | Ferreira, M. | Vingada, J.V. | Caurant, F.
In order to evaluate the use of biopsy samples as non-destructive tool for assessing trace element concentrations in small cetaceans, the concentrations of 14 trace elements were determined in skin, blubber, liver and kidneys of four species of small cetaceans (i.e. common dolphin Delphinus delphis, harbour porpoise Phocoena phocoena, bottlenose dolphin Tursiops truncatus and striped dolphin Stenella coeruleolba), stranded and/or by-caught along the NE Atlantic Ocean coast between 2001 and 2008. Only Cu, Fe, Hg, Mn, Ni and Zn were above the detection limit of the instruments and showed recoveries satisfactory enough to be interpreted. Among these trace elements, Hg was the only one showing a significant correlation between concentrations in and those in liver and kidneys. In consequence skin and blubber can only be used as non-invasive monitoring tissues to investigate Hg bioaccumulation in internal tissues for cetacean populations.
Show more [+] Less [-]Use of skin and blubber tissues of small cetaceans to assess the trace element content of internal organs Full text
2013
Aubail, A. | Méndez-Fernandez, P. | Bustamante, P. | Churlaud, C. | Ferreira, M. | Vingada, J. V. | Caurant, F.
In order to evaluate the use of biopsy samples as non-destructive tool for assessing trace element concentrations in small cetaceans, the concentrations of 14 trace elements were determined in skin, blubber, liver and kidneys of four species of small cetaceans (i.e. common dolphin Delphinus delphis, harbour porpoise Phocoena phocoena, bottlenose dolphin Tursiops truncatus and striped dolphin Stenella coeruleolba), stranded and/or by-caught along the NE Atlantic Ocean coast between 2001 and 2008. Only Cu, Fe, Hg, Mn, Ni and Zn were above the detection limit of the instruments and showed recoveries satisfactory enough to be interpreted. Among these trace elements, Hg was the only one showing a significant correlation between concentrations in and those in liver and kidneys. In consequence skin and blubber can only be used as non-invasive monitoring tissues to investigate Hg bioaccumulation in internal tissues for cetacean populations. | We greatly acknowledge the stranding networks from France (Observatoire PELAGIS), Spain (CEMMA), and Portugal (SPVS) for providing us cetacean samples. We also thank A. F. Guerra and F. Read from the Instituto de Investigaciones Marinas (C.S.I.C) in Vigo, Spain, and W. Dabin from the Observatoire PELAGIS in La Rochelle, France, for the age determination of the individuals. We also wish to thank C. Pignon-Mussaud from the Cellule Géomatique (UMR LIENSs) for providing the map of the study area and M. Kalombo from the Centre Commun d’Analyses (Fédération de Recherche en Environnement pour le Développement Durable FR 3097 CNRS-IFREMER-Université de La Rochelle) for running part of the trace element analyses. This work has been funded by the CPER 13 (Contrat de Plan Etat Région) through a post-doctoral grant to AA and PMF acknowledges support from the Portuguese Foundation for Science and Technology of the Government of Portugal (SFRH/BD/36766/2007). | published
Show more [+] Less [-]Distribution of local 137Cs anomalies on the seafloor near the Fukushima Dai-ichi Nuclear Power Plant Full text
2013
Thornton, B. (Blair) | Ohnishi, Seiki | Ura, Tamaki | Odano, Naoteru | Sasaki, Shun | Fujita, Tsuneo | Watanabe, Tomowo | Nakata, Kaoru | Ono, Tsuneo | Ambe, Daisuke
An estimated 3.5±0.7×1015Bq of 137Cs is thought to have been discharged into the ocean following the melt down at Fukushima Dai-ichi Nuclear Power Plant (F1NPP). While efforts have been made to monitor seafloor radiation levels, the sampling techniques used cannot capture the continuous distribution of radionuclides. In this work, we apply in situ measurement techniques using a towed gamma ray spectrometer to map the continuous distribution of 137Cs on the seafloor within 20km of the F1NPP. The results reveal the existence of local 137Cs anomalies, with levels of 137Cs an order of magnitude higher than the surrounding seafloors. The sizes of the anomalies mapped in this work range from a few meters to a few hundreds of meters in length, and it is demonstrated that the distribution of these anomalies is strongly influenced by meter scale features of the terrain.
Show more [+] Less [-]Influence of waste management policy on the characteristics of beach litter in Kaohsiung, Taiwan Full text
2013
Liu, Dagang | Wang, Meng-Wei | Chen, Ping
Marine debris is a ubiquitous problem that poses a serious threat to the global oceans; it has motivated public participation in clean-up campaigns, as well as governmental involvement in developing mitigation strategies. While it is known that the problem of marine litter may be affected by waste management practices on land, beach survey results have seldom been compared with them. In this study, marine litter surveys on four beaches of Cijin Island were conducted to explore the effects of waste management and policy implications. Indirect evidence shows that chances for land-based litter, such as plastic bags and bottles, entering the marine environment can be greatly decreased if they can be properly reduced, reused and recycled. We suggest that mitigation measures should focus on source reduction, waste recycling and management, utilizing effective economic instruments, and pursuing a long-term public education campaign to raise the public awareness of this problem.
Show more [+] Less [-]Distribution of the genus Alexandrium (Halim) and paralytic shellfish toxins along the coastline of New South Wales, Australia Full text
2013
Farrell, Hazel | Brett, Steve | Ajani, Penelope | Murray, Shauna
Blooms of Alexandrium species, in particular the species Alexandrium catenella, accounted for more than 50% of algal related, shellfish aquaculture harvest zone closures in New South Wales (NSW) Australia since 2005. While there are indications that species of Alexandrium are more abundant than they were formerly, there is little data available on the spatial and temporal distribution and abundance of the genus in NSW. A six and a half year dataset comprising a total of 8649 fortnightly samples from 31 estuaries spread over 2000km of NSW coastline was analysed. The greatest abundances of Alexandrium spp. were observed during the austral Spring and Summer, in estuaries in the mid and southern latitudes of the state. In identifying these high risk zones, we propose variables such as season, temperature, rainfall and estuarine flushing to be targeted in intensive site specific studies, to support the development of predictive tools for resource managers.
Show more [+] Less [-]The growth of coral reef science in the Gulf: A historical perspective Full text
2013
Burt, John A.
Coral reef science has grown exponentially in recent decades in the Gulf. Analysis of literature from 1950 to 2012 identified 270 publications on coral reefs in the Gulf, half of which were published in just the past decade. This paper summarizes the growth and evolution of coral reef science in the Gulf by examining when, where and how research has been conducted on Gulf reefs, who conducted that research, and what themes and taxa have dominated scientific interest. The results demonstrate that there has been significant growth in our understanding of the valuable coral reefs of the Gulf, but also highlight the fact that we are documenting an increasingly degraded ecosystem. Reef scientists must make a concerted effort to improve dialogue with regional reef management and decision-makers if we are to stem the tide of decline in coral reefs in the Gulf.
Show more [+] Less [-]Environmental impacts of tourism in the Gulf and the Red Sea Full text
2013
Gladstone, William | Curley, Belinda | Shokri, Mohammad Reza
The Gulf and Red Sea possess diverse coastal and marine environments that support rapidly expanding mass tourism. Despite the associated environmental risks, there is no analysis of the tourism-related literature or recent analysis of impacts. Environmental issues reported in 101 publications (25 from the Gulf, 76 from the Red Sea) include 61 purported impacts (27 from the Gulf, 45 from the Red Sea). Gulf literature includes quantitative studies (68% publications) and reviews (32%), and addresses mostly land reclamation and artificial habitats. Most Gulf studies come from Iran and UAE (64%). Red Sea literature includes quantitative studies (81%) and reviews (11%), with most studies occurring in Egypt (70%). The most published topics relate to coral breakage and its management. A full account of tourism’s environmental impacts is constrained by limited tourism data, confounding of impacts with other coastal developments, lack of baseline information, shifting baselines, and fragmentation of research across disciplines.
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