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1.
Corals are key members of the tropical reef communities, by providing habitat for other organisms and entering importantly into the overall metabolism of the reef community. Concern has been expressed several times at the collapse of the community that would result from damage to corals by oil pollution. So far relatively few experimental studies of the susceptibility of coral to oil have been carried out. In this study four Panamanian coral species have been exposed to marine diesel and bunker oil. These may cause delayed death, but probably more importantly interfere with feeding and metabolism at sub-lethal concentrations.  相似文献   

2.
Biofouling increases drag on marine vessels resulting in higher fuel consumption and can also facilitate the transport of harmful non-indigenous species (NIS). Antifouling technologies incorporating biocides (e.g., copper and tributyltin) have been developed to prevent settlement of organisms on vessels, but their widespread use has introduced high levels of contamination into the environment and raised concerns about their toxic effects on marine communities. The recent global ban on tributyltin (1 January 2008) and increasing regulation of copper have prompted research and development of non-toxic paints. This review synthesises existing information regarding the ecological impact of biocides in a wide range of organisms and highlights directions for the management of antifouling paints. We focus particularly on representatives of the recent past (copper and tributyltin) and present (copper and ‘booster’) biocides. We identify knowledge gaps in antifouling research and provide recommendations relating to the regulation and phasing-out of copper.  相似文献   

3.
An oil spill-food chain interaction model, composed of a multiphase oil spill model (MOSM) and a food chain model, has been developed to assess the probable impacts of oil spills on several key marine organisms (phytoplankton, zooplankton, small fish, large fish and benthic invertebrates). The MOSM predicts oil slick thickness on the water surface; dissolved, emulsified and particulate oil concentrations in the water column; and dissolved and particulate oil concentrations in bed sediments. This model is used to predict the fate of oil spills and transport with respect to specific organic compounds, while the food chain model addresses the uptake of toxicant by marine organisms. The oil spill-food chain interaction model can be used to assess the environmental impacts of oil spills in marine ecosystems. The model is applied to the recent Evoikos-Orapin Global oil spill that occurred in the Singapore Strait.  相似文献   

4.
The sinking of the tanker Eurobulker in Southern Evoikos gulf (Aegean Sea, Greece) in September 2000 resulted in a spill of 700 tons of crude oil. The environmental impact of the spill was studied by the National Centre for Marine Research. The hydrocarbon concentrations in water, sediment and coastal benthic organisms were measured and the response of the benthic communities to the disturbance caused by the oil spill was studied along the direction to the coast and over three sampling seasons. The most severe and direct effects were evidenced on the muddy benthic communities of the accident site and the stations in the close vicinity sampled shortly after the spill. The effects included reduction of the species richness and community diversity, but the communities reached full recovery 8 months later. The impact of the spill was more indirect and delayed in the coastal stations, where as the hydrocarbon measurements indicated, the pollutants were transported later and induced their effects on the benthic communities 6 months after the accident.  相似文献   

5.
On 3 December 1987, the supply ship Nella Dan ran aground at Macquarie Island (54°29′S, 158°58′E) releasing about 270 000 I of oil, mostly light marine diesel, into the sea. At the time of the incident, many marine invertebrates were washed up dead along 2 km of shoreline. Twelve months later, the shore community was investigated using 1. algal and invertebrate populations of the littoral and sublittoral rocky shore, and 2. the invertebrate communities living in the holdfasts of the giant kelp Durvillaea antarctica, which were collected for later examination. Investigations were undertaken at both affected and control locations. Analyses of differences in community structure involved nested ANOVA and multidimensional scaling techniques. On the rocky substrate, the effect of the spill was restricted to some biota of the lower littoral and sublittoral zones—particularly echinoderms and the patellid limpet Nacella macquariensis. There were differences in cover for some algal species between locations. Within the kelp holdfasts, communities were dominated by peracarid crustaceans at control locations and by polychaetes (particularly the opportunistic groups—capitellids, cirratulids and spionids) at oil-affected locations.

The communities have recently been re-surveyed (in the summer of 1994–1995) to assist in the interpretation of the results and to gauge the extent of recovery of the affected biota.  相似文献   


6.
The fate of linear alkylbenzenesulponates (LAS) in estuaries and coastal areas of the North Sea has been characterized with simple environmental models. The predicted concentration range in the estuaries around the North Sea (0.9-9 microg LAS l(-1)) was validated by monitoring data (1-9 microg LAS l(-1)). In offshore sites of the North Sea, it is estimated--and experimentally verified for a few sites--that the LAS concentration is below analytical detection limit (i.e., 0.5 microg LAS l(-1)). The effects of LAS on marine organisms have been reviewed. For short-term acute tests, there was no significant difference (p = 0.83) between the mean LC50 values of freshwater and marine organisms (mainly pelagic species tested, 4.1 and 4.3 mg LAS l(-1), respectively). For longer-term chronic tests, it appeared that the sensitivity (mean no-observed effect concentration (NOEC) value) of marine and freshwater organisms (0.3 and 2.3 mg LAS l(-1), respectively) was significantly different pt-test = 0.007). The predicted no-effect-concentrations (PNEC) were 360 and 31 microg LAS l(-1), for freshwater and marine pelagic communities, respectively. Given that the maximum expected estuarine and marine concentrations are 3 to > 30 times lower than the PNEC, the risk of LAS to pelagic organisms in these environments is judged to be low.  相似文献   

7.
A Canadian multi-authored appraisal of research on oil and dispersants has been completed recently. It resulted in a number of recommendations concerning research on oil spills, on relevant physical-chemical factors, effects of chemically dispersed oil on marine organisms, and strategies to minimize effects of oil spills in northern marine waters.  相似文献   

8.
Patterns of change in the structure of bacterial communities monitored by ribosomal intergenic spacer analysis (RISA) in oil contaminated sediments inhabited or not by the marine polychaete Nereis diversicolor were studied during 45 days under laboratory conditions. Results supported by principal component analysis showed a marked response of the bacterial communities to the oil contamination and to the presence of N. diversicolor. Phylogenetic affiliation of specific RISA bands showed that, in the contaminated sediments, the presence of the marine polychaetes favoured the development of bacteria which may play an active role in natural bioremediation processes of oil polluted environments.  相似文献   

9.
To assess risks of chemically-dispersed oil to marine organisms, oil concentrations in the water were simulated using a hypothetical spill accident in Tokyo Bay. Simulated oil concentrations were then compared with the short-term no-observed effect concentration (NOEC), 0.01 mg/L, obtained through toxicity tests using marine diatoms, amphipod and fish. Area of oil concentrations higher than the NOEC were compared with respect to use and non-use of dispersant. Results of the simulation show relatively faster dispersion near the mouth of the bay compared to its inner sections which is basically related to its stronger water currents. Interestingly, in the inner bay, a large area of chemically-dispersed oil has concentrations higher than the NOEC. It seems emulsifying oil by dispersant increases oil concentrations, which could lead to higher toxicity to aquatic organisms. When stronger winds occur, however, the difference in toxic areas between use and non-use of dispersant is quite small.  相似文献   

10.
Different levels of eutrophication and pollution in the Baltic coastal waters in general, and in estuaries particularly define variations in the buffering capacity of ecosystems of these important filter zones between rivers and the adjacent Baltic Proper. Phyto- and zooplankton in the estuaries form important components of the pelagic food webs that participate in producing and structuring the matter, energy, and information fluxes in the ecosystems. Due to salinity gradients, estuaries provide a large variety of aquatic habitats for native populations of marine, brackish and fresh water plankton species. Non-indigenous planktonic species that expand their bio-geographical range and invade the Baltic coastal ecosystems also find favourable environments, establish permanent populations there, and impact aboriginal ecosystems. The dynamics of abundance, species diversity, population structure, productivity of planktonic communities, and peculiarities of trophic interactions in different Baltic estuaries are influenced by a number of common environmental factors. Being measured on the unified basis and monitored, changes (or stability) of structural and functional parameters of plankton communities can serve as indicators of alterations to the ecosystems. Comparative analyses and quantitative estimates of long-term changes in phyto- and zooplankton can contribute to evaluation of functional response of Baltic coastal ecosystems to anthropogenic stress. Both theoretical (modeling) and empirical studies of interactions within plankton communities aimed at the assessment of the role of planktonic organisms in water quality regulation, and applicability of these data for the evaluation of the status of ecosystems and their management can be considered as major goals for the future investigations in Baltic estuaries.  相似文献   

11.
Non-eroding silicone-based coatings can effectively reduce fouling of ship hulls and are an alternative to biocidal and heavy metal-based antifoulings. The products, whose formulations and make up are closely guarded proprietary knowledge, consist of a silicone resin matrix and may contain unbound silicone oils (1-10%). If these oils leach out, they can have impacts on marine environments: PDMS are persistent, adsorb to suspended particulate matter and may settle into sediment. If oil films build up on sediments, infiltration may inhibit pore water exchange. PDMS do not bioaccumulate in marine organisms and soluble fractions have low toxicity to aquatic and benthic organisms. At higher exposures, undissolved silicone oil films or droplets can cause physical-mechanic effects with trapping and suffocation of organisms. These 'new' effects are not covered by current assessment schemes. PDMS make the case that very low water solubility and bioavailability do not necessarily preclude damage to marine environments.  相似文献   

12.
The discovery of high levels of tributyltin compounds in Antarctic marine sediments has prompted managers to consider the banning of such substances in this region. We propose that the banning of antifouling coatings may result in an increase in the risk of non-indigenous species invasions. Our studies show that un-treated vessels carry a more diverse community of fouling organisms than treated hulls on which fouling is restricted to specific untreated niches. Up to 40% of the species recruited to the hulls of Southern Ocean vessels are species with invasive histories. Viable fouling assemblages can survive prolonged voyages to high-latitude coastlines, yet passage through sea-ice may remove fouling communities due to mechanical abrasion reducing the hazard of introductions to ice-bound coastlines. The banning of antifouling compounds may be of particular concern for the ice-free sub-Antarctic islands which represent a common anchorage point for vessels on-route to Antarctica.  相似文献   

13.
Gray's Reef National Marine Sanctuary (GRNMS) is an increasingly popular site for recreational fishing and diving in the South Atlantic Bight (SAB). As a result, there has been heightened concern about potential accumulation of marine debris and its consequent effects on sanctuary resources. Field surveys were conducted at GRNMS in 2004 and 2005 to provide a spatially comprehensive characterization of benthic communities and to quantify the distribution and abundance of marine debris in relation to bottom features. The spatial distribution of debris was concentrated in the center of the sanctuary and was most frequently associated with ledges rather than other bottom types. On ledges, the presence and abundance of debris was significantly related to observed boating activity and physiographic features including ledge height, ledge area, and percent cover of benthic organisms. The results from this study will aid managers in optimizing cleanup efforts and long-term monitoring of debris accumulation patterns at GRNMS and other hard bottom areas in the SAB.  相似文献   

14.
It is proposed that a new, fifth era should be added to the four historical phases of marine research identified by Rupert Riedl, specifically an era devoted to studying and ameliorating disturbed marine ecosystems. In an age of global environmental deterioration, many marine ecosystems and organisms are high on the list of threatened entities. This poor status prompts research that would otherwise have been unnecessary and hinders research that would normally have been conducted. I argue that research into intact marine ecosystems is becoming increasingly difficult, and that most of our future insights into marine habitats will stem from knowledge gained by examining various disfunctions of those systems rather than their functions. The new era will therefore differ from past research in its underlying aim, the range of topics studied, the selection and funding of those topics, the validity of its conclusions, and in its urgency. Sea turtles and cetaceans are cited as case studies at the organismic level, shallow-water benthic communities, including coral reefs, at the ecosystem level.  相似文献   

15.
The history of aquatic environmental pollution goes back to the very beginning of the history of human civilization. However, aquatic pollution did not receive much attention until a threshold level was reached with adverse consequences on the ecosystems and organisms. Aquatic pollution has become a global concern, but even so, most developing nations are still producing huge pollution loads and the trends are expected to increase. Knowledge of the pollution sources and impacts on ecosystems is important not only for a better understanding on the ecosystem responses to pollutants but also to formulate prevention measures. Many of the sources of aquatic pollutions are generally well known and huge effort has been devoted to the issue. However, new concepts and ideas on environmental pollution are emerging (e.g., biological pollution) with a corresponding need for an update of the knowledge. The present paper attempts to provide an easy-to-follow depiction on the various forms of aquatic pollutions and their impacts on the ecosystem and organisms.  相似文献   

16.
Hypoxia: from molecular responses to ecosystem responses   总被引:24,自引:0,他引:24  
  相似文献   

17.
Sediments and marine organisms such as mussels (Mytilus galloprovincialis), fish (Mullus barbatus, Serranus scriba), crabs (Polybius henslowi) and shrimp-like crustaceans (mysids, euphausiids) were sampled on European coasts, France, Spain) and analysed for their PAH content by gas chromatography/mass spectrometry (GC-MS). The PAH concentrations determined in the organisms were significantly negatively correlated with logKow values, but to different extents according to the species. This was explained by the greater exposure of the organisms to the lower molecular weight compounds with differences resulting from different feeding habits, habitat, and biotransformation capacities of the organisms in relation to trophic levels. The influence of these observations on the use of different sentinel species in biomonitoring programmes is discussed.  相似文献   

18.
Marine biodiversity in almost all oceans is being threatened at the genetic, species, and ecosystem levels. The marine ecosystem is being degraded and the extinction rate of marine organisms has accelerated. In this paper, the potential causes of fishery resource exhaustion in the East China Sea are analyzed, including the change in the stoichiometric composition of seawater with regard to the concentrations of N and P, toxic effects of marine pollution, marine habitat destruction, increased seawater temperatures caused by climate warming, ocean acidification, pressure from overfishing, and the spread of marine pathogenic bacteria. It is believed that the factors mentioned above have significant impact on the exhaustion of fishery resources in the East China Sea. However, considering the cumulative, synergistic, and superimposed effects as well as the amplification effects resulting from their interactions, the actual risk of ecological extinction of marine organisms might be even more severe than that previously estimated. Hence, ecosystem management and research focused on a single risk factor or influencing factor is not enough to prevent marine ecosystem degradation and fishery resource exhaustion. A comprehensive, systematic, effective, and ecosystem-based management policy is imperative for healthy and sustainable fishery development in the East China Sea.  相似文献   

19.
An estimated 10–20 000 seabirds were killed by a very small oil spill off the coast of North Norway in March 1979. Despite the fact that over 90% of these were Brunnich's Guillemots Uria lomvia, the breeding population of this species was not considered to have been seriously threatened by this spill. On the other hand, this episode did illustrate how extremely vulnerable certain seabird species are to oil.  相似文献   

20.
Selected key components of the continental shelf benthic and demersal communities were monitored for the two years following the Prestige oil spill (POS) in order to identify the possible ecological effects of the oil. This work includes the first results regarding changes in abundance, distribution and food habits of hake (Merluccius merluccius), four-spot megrim (Lepidorhombus boscii), Norway lobster (Nephrops norvegicus) and Pandalid shrimp (Plesionika heterocarpus) populations of Galician and Cantabrian Sea shelves following the POS. Significant reductions in the abundance of Norway lobster, Plesionika heterocarpus and four-spot megrim were detected in the POS maximum impact area, located over the Galician shelf. Noteworthy recoveries were observed in the 2004 abundance indices of four-spot megrim and Plesionika. On the other hand, no significant effects were detected in the abundance or distribution of hake juveniles even though the tar aggregates were bound by the same oceanographic drift events as the hake recruits were during the winter of 2003 (Navidad current) in different water column layers of the Cantabrian Sea. Feeding patterns of the four species analysed did not present apparent modifications that can be related to the POS.  相似文献   

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