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1.
There are increasing concerns regarding the delivery, movement and presence of non-indigenous or invasive species into marine and estuarine areas. Such introductions can be on a large scale such as the movement to higher latitudes of species as the result of global warming. Alternatively, such species can be introduced into a marine or estuarine area as the result of small-scale events, such as the liberation from waste-water discharges, aquaculture or ballast-water discharge. However, if such introductions lead to a successful colonisation then they can become a wide-scale problem. This paper considers the introduction of such non-indigenous and invasive species as biological pollution and biological pollutants and it discusses the definitions and concepts used in assessing and managing marine pollution in relation to these terms.  相似文献   

2.
Adverse effects of invasive alien species (IAS), or biological pollution, is an increasing problem in marine coastal waters, which remains high on the environmental management agenda. All maritime countries need to assess the size of this problem and consider effective mechanisms to prevent introductions, and if necessary and where possible to monitor, contain, control or eradicate the introduced impacting organisms. Despite this, and in contrast to more enclosed water bodies, the openness of marine systems indicates that once species are in an area then eradication is usually impossible. Most institutions in countries are aware of the problem and have sufficient governance in place for management. However, there is still a general lack of commitment and concerted action plans are needed to address this problem. This paper provides recommendations resulting from an international workshop based upon a large amount of experience relating to the assessment and control of biopollution.  相似文献   

3.
The ongoing transfer of harmful organisms by shipping, especially via ballast water transport, may result in a change of biodiversity, alteration of ecosystems, negative impacts on human health and economic loss. Species introductions which cause irreversible consequences to receiving environments and economies call for particular attention. One critical issue is a need to evaluate the quantities and processes of species introductions. Consequently ballast water was sampled on 15 ships calling at the Port of Koper, Slovenia. This was the first ballast water sampling study in the Mediterranean Sea. This paper summarises the sampling results. Samples were analysed for all types of aquatic organisms including bacteria. The results may be considered as background information for an initial risk assessment of future species introductions - an important tool for the implementation of ballast water management measures.  相似文献   

4.
This article assesses the ecological and economic impacts of land reclamation and dredging through consulting recent environmental impact assessment reports. Geographic features of Bahrain during 1963-2008 are produced using Geographical Information System. Extensive but inexpensive shallow coastal areas and tidal flats have been reclaimed particularly from 1997 to 2007 at a high rate of 21 km(2)/year. Formal records show the increase in the original land mass by the year 2008 to be 91 km(2). An estimated total cumulative loss of major habitats resulting from 10 reclamation projects was around 153.58 km(2). Also much larger scale impacts should be considered resulting from the borrow areas used for the extraction of sand or infill materials. A number of key habitats and species are affected in the vicinity of these projects. The study attempts to assign a monetary value to the marine ecosystem functions. There is a need for efficient coastal zone management to regulate a sustainable use of the marine resources.  相似文献   

5.
Coastal ecosystems are impacted by many stressors, of which chemicals are possibly not the most important. Chemicals differ from most other stressors such as eutrophication and hypersedimentation in the time scale-effects from the latter act on the scale of weeks or months, whereas effects from chemicals may take years to manifest themselves in population or community changes. There are four different approaches available to manage chemicals in marine ecosystems: target contaminant levels, target individual effects, target community impacts (biodiversity) and, finally, target processes. These four differ in the analytical methods available and the analyst's ability to separate effects from chemicals from other environmental factors and natural variation. There is furthermore, a need to develop a framework to integrate biological effects methods with risk assessment methodology. Such integration will improve the basis for risk-based assessment of chemicals. A problematic issue relevant to all aspects of environmental management are the interactions between chemicals, and between chemicals and eutrophication or sedimentation. There is a clear need for more knowledge about such interactions.  相似文献   

6.
The introduction of alien species (AS) in marine environments is a factor of disturbance that can be viewed as a pollution agent. Using basic information on abundance and distribution of alien species, we developed an index that classifies AS impacts on native species, communities, habitats and ecosystem functioning. This method can be used to evaluate impact at five different levels of biopollution, fitting within the existing schemes for water quality assessment. Both spatial and temporal comparisons are possible. The assessments may also be used to evaluate management performance where avoidance measures were necessary and assist in preventing further unwanted introductions. Such assessments made for the same areas over time provide opportunities for measuring change in biopollution. We have tested the method using four different well-studied areas within the Baltic Sea (brackish to freshwater environments) for two different times, 20 years apart. Further developments of the scheme may be needed to cover some specific cases and taxonomic groups according to their life history.  相似文献   

7.
The paper gives a personal overview of fisheries management including the background to sustainable yield and the increasing importance of marine research for fisheries. It gives the characteristics of the marine environment, including the atmosphere, for international fisheries management. Conservation and the need for multispecies management are required and the paper discusses the increases in incidental catch and the effects of overfishing on target and by catch stocks. There are specific concerns of high seas management, including overlapping (straddling) and highly migratory fish stocks. The paper discusses fisheries management against a background of Agenda 21 of the Rio Conference and the 1982 UN Convention on the Law of the Sea.  相似文献   

8.
Adaptive management of the marine environment requires an understanding of the complex interactions within it. Establishing levels of natural variability within and between marine ecosystems is a necessary prerequisite to this process and requires a monitoring programme which takes account of the issues of time, space and scale. In this paper, we argue that an ecosystem approach to managing the marine environment should take direct account of climate change indicators at a regional level if it is to cope with the unprecedented change expected as a result of human impacts on the earth climate system. We discuss the purpose of environmental monitoring and the importance of maintaining long-term time series. Recommendations are made on the use of these data in conjunction with modern extrapolation and integration tools (e.g. ecosystem models, remote sensing) to provide a diagnostic approach to the management of marine ecosystems, based on adaptive indicators and dynamic baselines.  相似文献   

9.
10.
Biosecurity management allows countries to meet a number of international obligations and provides some protection from potential degradation of environmental, economic, social and cultural values. Ocean governance relies on the precepts of ecologically sustainable development to manage the multiple uses in the coastal zone. The increasing reliance on aquaculture to provide food security and economic development has led to an increase in the use of non-native target species grown as food sources. Increased economic activity has led to shifting trade patterns and increased efficiencies in vessels with the resulting increase in the number of introduced marine species via ballast water and hull fouling. Herein we review the different marine biosecurity strategies and legislation that have been implemented internationally and locally that aid in preventing and managing introduced marine species, with some attention to Australia and New Zealand as examples. Typical tools being used include quarantine, Import Health Standards, voluntary cleaning guidelines, and risk assessment, all of which aim to prevent introductions.  相似文献   

11.
Harbour porpoises sampled within the UK Cetacean Strandings Investigation Programme have been analysed for 25 chlorobiphenyl congeners. In all, 440 porpoises stranded or bycaught during the period 1991-2005 were studied. There are regional differences in the trend in summed congener concentrations over time but, despite controls on PCBs having been in place for decades, they are declining only slowly. Their toxic impacts in UK porpoises - increased susceptibility to infectious disease mortality in the most contaminated individuals - looks likely to continue for some time yet. Further efforts to limit or eliminate PCB discharges to the marine environment are still needed.  相似文献   

12.
Invasions are common in coastal marine environments where proximity to urban areas should influence the number of non-native organisms due to the likelihood of unintentional introductions from urban centers. Invasive species are widely recognised as important agents of global change, and can colonize new habitats and even cause local extinction of native species. This study was focused on the invasive marine macroalga Sargassum muticum, a problematic invasive species on the West coast of America and in European waters. An intensive survey was carried out along the Galician coast (North West of Spain) from March to August 2008 to determine the current distribution of this species, and its relationship with level of urbanization and native macroalgal diversity. We sampled the presence of S. muticum and native macroalgae in the mid and low intertidal zones of twenty rocky shores distributed along ten rias. Rias were grouped into high and scarcely urbanized based on their population density. Results indicated that S. muticum was present in nine out of the ten rias, confirming its presence in most of the intertidal rocky shores of Galicia twenty years after it was first observed. The presence of S. muticum was not related to the degree of urbanization of the rias, and its distribution and abundance did not seem to be influenced by diversity or functional groups of native algae. In addition, there was a great variability in the percentage cover, number and length of individuals amongst localities and rias suggesting that both large-scale and local processes may play a role in the distribution of this species. This study highlights the importance of future research into the distribution and impact of introduced algae and proves the urgent need for monitoring programmes and increasing efforts to prevent and control new introductions.  相似文献   

13.
Marine legislation world-wide has, as a recent final objective, the maintenance of a good environmental or ecological status for marine waters, habitats and resources. The concept of environmental status takes into account the structure, function and processes of marine ecosystems, bringing together physical, chemical, physiographic, geographic and climatic factors: subsequently, integrating such conditions, with anthropogenic impacts and activities undertaken in the area concerned. Such an approach is intended to permit an assessment of the environmental status at the ecosystem level, i.e. ‘ecosystem-based approach’, or ‘ecosystem-based management’.Such legislation emphasises the need for the development of methodologies, to assess environmental status. As such the knowledge acquired within Regional Seas, discussed at International Symposia and, finally, published as Special Issues, can serve as the basis for a regional ecosystem-based approach to management and the integrative assessment of marine systems. Hence, the Bay of Biscay is used in this contribution, as an example, to show past and present research, together with perspectives for the future. It is concluded that collaboration between institutions (marine research institutes, universities) and countries (France, Spain, Portugal, the United Kingdom and Ireland) could result in an interesting ‘case-study’, for the further implementation of the European Marine Strategy Framework Directive, at the level of this particular Regional Sea. In this way, the experience gained in the implementation of the Water Framework Directive within the ecoregion, together with the information collated in the eleven International Symposia of Oceanography of the Bay of Biscay, celebrated until now, can be very useful, for an ecosystem-based management approach for this Regional Sea.  相似文献   

14.
Hypoxia alters the oxidation–reduction balance and the biogeochemical processes in sediments, but little is known about its impacts on the microbial community that is responsible for such processes. In this study, we investigated the effects of hypoxia and the ubiquitously dispersed flame-retardant BDE47 on the bacterial communities in marine surface sediments during a 28-days microcosm experiment. Both hypoxia and BDE47 alone significantly altered the bacterial community and reduced the species and genetic diversity. UniFrac analysis revealed that BDE47 selected certain bacterial species and resulted in major community shifts, whereas hypoxia changed the relative abundances of taxa, suggesting slower but nonetheless significant community shifts. These two stressors targeted mostly different taxa, but they both favored Bacteroidetes and suppressed Gammaproteobacteria. Importantly, the impacts of BDE47 on bacterial communities were different under hypoxic and normoxic conditions, highlighting the need to consider risk assessments for BDE47 in a broader context of interaction with hypoxia.  相似文献   

15.
The Great Barrier Reef Marine Park (GBRMP) is an ecosystem whose ecological features are recognized internationally. There is a need to evaluate the impacts of historical and contemporary changes in land use on the GBRMP. This paper quantifies pesticide inputs in the Herbert River catchment of North Queensland in the context of changes in land use over the last 100 years. We show that three major phases of rural land use and land cover change have occurred, with large areas of native vegetation converted to agricultural production. The increase in agricultural land has seen a corresponding increase in the area receiving pesticides. We present data showing application histories for organochlorine, organophosphate, phenoxy, triazine, urea, mercurial and azole group pesticides. While the fate of these pesticides in aquatic and marine systems is largely unknown, these trends pose a significant challenge for agricultural industries in complying with the principles of ecologically sustainable development (ESD).  相似文献   

16.
It can be argued that the intensity of monitoring of coastal marine environments lags behind the equivalent terrestrial environments. This results in a paucity of long-term time series of key environmental parameters such as turbidity. This lack of management information of the sources and sinks, and causes and impacts of stressors to the coastal marine environment, along with a lack of co-ordination of information collection is compromising the ability of environmental impact assessments of major coastal developments to discriminate between local and remote anthropogenic impacts, and natural or background processes. In particular, the quasi outsourcing of the collection of coastal information can lead to a perverse incentive whereby in many cases nobody is actively or consistently monitoring the coastal marine environment effectively. This is particularly the case with regards to the collection of long-term and whole-of-system scale data. This lack of effective monitoring can act to incentivise poor environmental performance.  相似文献   

17.
Groundwater management planning requires balancing the interests of different stakeholder groups because (1) water supply development causes changes to groundwater systems that include declines in groundwater levels and (2) benefits and costs from pumping the common-pool resource often do not occur such that they are shared proportionate to use. Quantifying impacts from declining groundwater levels among user groups can be useful for evaluating management strategies. In California, considering impacts to supply well operations is proving important for acceptance of management plans that have been required by law. A case study is presented to illustrate the types of results that may contribute to the planning process. The results indicate that significant differences in impact may occur between groundwater pumpers. Suggestions are provided for using this information to mitigate impacts to the most vulnerable stakeholders.  相似文献   

18.
Physical and biological seabed impacts can persist long after the cessation of marine aggregate dredging. Whilst small-scale experimental studies have shown that it may be possible to mitigate such impacts, it is unclear whether the costs of restoration are justified on an industrial scale. Here we explore this question using a case study off the Thames Estuary, UK. By understanding the nature and scale of persistent impacts, we identify possible techniques to restore the physical properties of the seabed, and the costs and the likelihood of success. An analysis of the ecosystem services and goods/benefits produced by the site is used to determine whether intervention is justified. Whilst a comparison of costs and benefits at this site suggests restoration would not be warranted, the analysis is site-specific. We emphasise the need to better define what is, and is not, an acceptable seabed condition post-dredging.  相似文献   

19.
Current predictions as to the impacts of climate change in general and Arctic climate change in particular are such that a wide range of processes relevant to Arctic contaminants are potentially vulnerable. Of these, radioactive contaminants and the processes that govern their transport and fate may be particularly susceptible to the effects of a changing Arctic climate. This paper explores the potential changes in the physical system of the Arctic climate system as they are deducible from present day knowledge and model projections. As a contribution to a better preparedness regarding Arctic marine contamination with radioactivity we present and discuss how a changing marine physical environment may play a role in altering the current understanding pertaining to behavior of contaminant radionuclides in the marine environment of the Arctic region.  相似文献   

20.
This special issue of Continental Shelf Research contains 20 papers giving research results produced as part of Australia's Torres Strait Co-operative Research Centre (CRC) Program, which was funded over a three-year period during 2003–2006. Marine biophysical, fisheries, socioeconomic-cultural and extension research in the Torres Strait region of northeastern Australia was carried out to meet three aims: 1) support the sustainable development of marine resources and minimize impacts of resource use in Torres Strait; 2) enhance the conservation of the marine environment and the social, cultural and economic well being of all stakeholders, particularly the Torres Strait peoples; and 3) contribute to effective policy formulation and management decision making. Subjects covered, including commercial and traditional fisheries management, impacts of anthropogenic sediment inputs on seagrass meadows and communication of science results to local communities, have broad applications to other similar environments.  相似文献   

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