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1.
Seagrass meadows are valuable ecosystem service providers that are now being lost globally at an unprecedented rate, with water quality and other localised stressors putting their future viability in doubt. It is therefore critical that we learn more about the interactions between seagrass meadows and future environmental change in the anthropocene. This needs to be with particular reference to the consequences of poor water quality on ecosystem resilience and the effects of change on trophic interactions within the food web. Understanding and predicting the response of seagrass meadows to future environmental change requires an understanding of the natural long-term drivers of change and how these are currently influenced by anthropogenic stress. Conservation management of coastal and marine ecosystems now and in the future requires increased knowledge of how seagrass meadows respond to environmental change, and how they can be managed to be resilient to these changes. Finding solutions to such issues also requires recognising people as part of the social–ecological system. This special issue aims to further enhance this knowledge by bringing together global expertise across this field. The special issues considers issues such as ecosystem service delivery of seagrass meadows, the drivers of long-term seagrass change and the socio-economic consequences of environmental change to seagrass. 相似文献
2.
Olenin S Elliott M Bysveen I Culverhouse PF Daunys D Dubelaar GB Gollasch S Goulletquer P Jelmert A Kantor Y Mézeth KB Minchin D Occhipinti-Ambrogi A Olenina I Vandekerkhove J 《Marine pollution bulletin》2011,62(12):2598-2604
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.
Stephen Anthony Mitchell 《Aquatic Sciences - Research Across Boundaries》2013,75(1):95-112
The larger wetlands of Sub-Saharan Africa, cover 2,072,775 km2 (9.01 %) of the landmass. This paper reviews the major threats, including climate change, to these wetlands, a number of which lie in semi-arid regions. Climate change predictions are that the arid or semi-arid regions of Africa in the latitudes around the Tropics of Capricorn and Cancer will become drier. The future of wetlands is allied to human well-being, and the effects of climate change cannot be de-linked from human activities occurring in and around wetlands. The high productivity of wetlands supports substantial populations of poor people dependent on ecosystem services for at least part of their livelihood. This is particularly so in the semi-arid Sahel in the North and equivalent latitudes in the south, which are seen as vulnerable to climate change largely due to high levels of poverty and low adaptive capacity. While sustainable ecosystem management is a long-term goal, survival is more immediate to poor people depending on ecosystem services for their livelihoods. Population increase and a decrease in the resource base due to predicted decreased rainfall will lead to over exploitation of the resource base. Certain engineering interventions redistribute ecosystem services to the benefit of those upstream or away from the river system. Governance systems play a key role in the sustainable management of resources. Breakdown of governance systems through civil war is seen as a driver of poverty and a major cause of breakdown in resource conservation, increasing the dependence of poor people on ecosystems. 相似文献
4.
The adverse ecological effects of elevated levels of phosphorus (P) and fine sediment (termed silt) in surface waters are a major environmental issue both nationally and internationally. Increasingly, the Water Framework Directive (WFD) will provide the basis for the integrated management of European waters, but there is a more immediate need for action to safeguard designated wildlife sites from the effects of eutrophication and siltation. We outline the policy drivers behind the control of these pollution problems, the nature and extent of ecological risks and approaches to target-based management within catchments. Tackling diffuse sources of P and silt requires accurate apportionment of local sources and contributing areas, and integration of practical action with the development of an improved quantitative understanding of the management changes needed in catchments to meet environmental objectives. Such an approach can be used to refine policies on land-based emissions of these pollutants and operational strategies for control. The critical role of catchment appraisal through modelling within this approach is stressed. Management measures to control agricultural sources of P and silt will also help to address other key catchment management objectives (flood risk management, water resource management, terrestrial and wetland habitat restoration). Climate change predictions indicate that the need for integrated catchment management, to increase the resilience of catchments, wildlife and people to extremes of weather conditions (drought and flood) and temperature trends, has never been greater. 相似文献
5.
The keynote paper by Garrett Hardin 44 years ago introduced the term 'tragedy of the commons' into our language (Hardin, 1968); this term is now used widely, but it is neither universally accepted nor fully understood. Irrespective, the 'tragedy of the commons' is an increasing reality for more than 500 million people that rely on the biodiversity resources and services of tropical coral reefs, mangrove forests, seagrass beds and associated fisheries. These natural resources continue to decline despite major advances in our scientific understanding of how ecosystems and human populations interact, and the application of considerable conservation and management efforts at scales from local user communities to oceans. Greater effort will be required to avert increasing damage from over-exploitation, pollution and global climate change; all deriving from increasing exploitation driven by poverty and progress i.e. continuing to expand development indefinitely and extraction of resources at industrial scales. However, the 'tragedy' concept has been widely criticized as a simple metaphor for a much larger set of problems and solutions. We argue that the 'tragedy' is essentially real and will continue to threaten the lives of millions of people unless there are some major moral and policy shifts to reverse increasing damage to coastal habitats and resources. We agree with the conclusion by Hardin that the solution to the tragedy will not be through the application of natural sciences, but via implementing exceedingly difficult and controversial moral decisions. An extreme example of a moral and controversial direction suggested by Hardin was in re-examining the 'freedom to breed' as an inherent human value. The need for 'moral decisions' is even greater in 2012. 相似文献
6.
Dennis P. Tihansky 《Marine pollution bulletin》1973,4(10):149-153
Increasing pollution of estuaries and coastal waters causes economic damage to fisheries, tourism and much else. Developing countries are not immune from this, and the growth of tourism as well as the shift of populations to the coast in many parts of the world make pollution control all the more urgent. The problem is an international one and demands international solutions, but before these are likely, a good deal more hard information will be needed. 相似文献
7.
The mappings of poverty and food insecurity were carried out for the rural districts of the four riparian countries (Botswana, Mozambique, South Africa and Zimbabwe) of the Limpopo river basin using the results of national surveys that were conducted between 2003 and 2013. The analysis shows lower range of food insecure persons (0–40%) than poverty stricken persons (0–95%) that is attributable to enhanced government and non-government food safety networks in the basin countries, the dynamic and transitory nature of food insecurity which depends on the timings of the surveys in relation to harvests, markets and food prices, and the limited dimension of food insecurity in relation to poverty which tends to be a more structural and pervasive socio-economic condition. The usefulness of this study in influencing policies and strategies targeted at alleviating poverty and improving rural livelihoods lies with using food insecurity mappings to address short-term socio-economic conditions and poverty mappings to address more structural and long-term deprivations. Using the poverty line of $1.25/day per person (2008–2013) in the basin, Zimbabwe had the highest percentage of 68.7% of its rural population classified as poor, followed by Mozambique with 68.2%, South Africa with 56.1% and Botswana with 20%. While average poverty reduction of 6.4% was observed between 2003 and 2009 in Botswana, its population growth of 20.1% indicated no real poverty reduction. Similar observations are made about Mozambique and Zimbabwe where population growth outstripped poverty reductions. In contrast, both average poverty levels and population increased by 4.3% and 11%, respectively, in South Africa from 2007 to 2010. While areas of high food insecurity and poverty consistently coincide with low water availability, it does not indicate a simple cause–effect relationship between water, poverty and food insecurity. With limited water resources, rural folks in the basin require stronger institutions, increased investments and support to enable them generate sufficient income from their rain-fed farming livelihood to break out of the poverty cycle. 相似文献
8.
Galloway TS 《Marine pollution bulletin》2006,53(10-12):606-613
Marine pollution is a major threat to human and environmental health. Given the complexity of function of marine and coastal ecosystems, it is unlikely that a balanced view of the nature and extent of risk will easily be achieved if human and environmental risk assessments continue to be conducted in isolation. Here, the integration of assessment protocols is advocated as a holistic means of improving risk management. Biomarkers can provide the common conceptual framework and measurable endpoints necessary for successful integration. Examples are given of the ways in which suites of biomarkers encompassing molecular change, cellular pathology and physiological impairment can be developed and adapted for human and ecological scenarios. By placing a greater emphasis on the health status of impacted biota, it is more likely that risk assessment will develop the efficiency, reliability and predictive power to adapt to the unforeseen environmental threats that are an inevitable consequence of human development and global change. 相似文献
9.
Interactions between climate change and contaminants 总被引：1，自引：0，他引：1
There is now general consensus that climate change is a global threat and a challenge for the 21st century. More and more information is available demonstrating how increased temperature may affect aquatic ecosystems and living resources or how increased water levels may impact coastal zones and their management. Many ecosystems are also affected by human releases of contaminants, for example from land based sources or the atmosphere, which also may cause severe effects. So far these two important stresses on ecosystems have mainly been discussed independently. The present paper is intended to increase awareness among scientists, coastal zone managers and decision makers that climate change will affect contaminant exposure and toxic effects and that both forms of stress will impact aquatic ecosystems and biota. Based on examples from different ecosystems, we discuss risks anticipated from contaminants in a rapidly changing environment and the research required to understand and predict how on-going and future climate change may alter risks from chemical pollution. 相似文献
10.
11.
Toyofuku H 《Marine pollution bulletin》2006,53(10-12):579-590
For over centuries developments in food production and new food safety management systems in most developed countries have been perceived by many to be efficient in the prevention of food-borne disease. Nevertheless a number of problems remain dominant, one of these being the high level of food-borne microbiological disease which seems, for some pathogens, to have increased over the last decades. The development of an interdisciplinary approach with direct interaction between surveillance and risk analysis systems is described as a potential basis for improved prevention of food-borne disease. Quantitative microbiological risk assessment is a relatively new scientific approach, able to link data from food within the entire food chain and the various data on human disease to provide a clear estimation of risk. Today food safety is one of the WHOs top eleven priorities; the Organization calls for more systematic and aggressive steps to be taken to reduce significantly the risk of microbiological food-borne diseases. Dealing with this challenge is one of the major challenges for the 21st century in regard to food safety, implying a significant re-direction of food microbiology efforts in many parts of the world. 相似文献
12.
Kuijper MW 《Marine pollution bulletin》2003,47(1-6):265-272
UNESCO is one of the specialized agencies under the United Nations charged with the advancement and improvement of education, social and natural sciences, culture and communication. This global mandate translates into programmes in the field tailored to the member states' specific requirements that build on the full breadth of expertise available in UNESCO. Environmental awareness building is an integral component of many of UNESCO's programmes. This paper describes how UNESCO addresses the need for awareness building in a variety of settings under different programmes and sectors. A first example is taken from the work of the education sector, which aims at introducing innovative learning methods and curricula that change or cultivate the perspective of people of all ages on sustainable development. The second example is taken from the Man and Biosphere Programme. The Biosphere Reserve concept has had a long history within UNESCO and is increasingly applied to protected areas in the coastal zone. Notable examples are Ranong Biosphere Reserve in Thailand, Can Gio Biosphere Reserve in Vietnam and the Island of Palawan in the Philippines. The concept is currently experiencing a revival as more and more countries realize the importance of striking a balance between human development and strict conservation. Many people know about UNESCO through the so-called World Heritage Sites. These are sites that are recognized by the world community as particular monuments, either natural or cultural, that warrant preservation for the whole of mankind. In the Asia-Pacific region, there are quite a number of coastal and marine sites that have been designated as natural world heritage sites, e.g. Halong Bay in Vietnam, the Komodo marine national park, Indonesia, the Great Barrier Reef in Australia, East-Rennell Island in the Solomon Islands, and Tubbataha Reef in the Philippines. The need for a cross-sectoral approach is evident under the so-called Coastal Zone and Small Islands endeavour, which aims at assisting Member States towards environmentally sound, socially equitable and culturally appropriate development in coastal regions and in small islands. Four examples of current pilot projects (Surin Island, Thailand, Jakarta Bay, Indonesia, Upolo Island, Samoa and Ulugan Bay, the Philippines) are highlighted. Each setting and each audience requires a different strategy. UNESCO's strength is to learn from all these experiences and make such new insights universally available and to put novel concepts into practice. 相似文献
13.
Sir Martin Holdgate 《Marine pollution bulletin》1994,29(6-12):258-261
The oceans have a major influence on world climate and are an important source of food, most of which comes from the coastal zones. These zones, and the traditional, sustainable, life-styles of the fishing communities that live there, are under immense and growing pressure. Urbanization, pollution, sea level rise, and the destruction of natural coast defences and fish nursery grounds are undermining sustainability. Although chemical pollution in some areas, with some substances, is falling it remains a serious problem over the world as a whole.
The United Nations Conference on the Human Environment, held at Rio de Janeiro in June 1992, recognized the need for more effective protection of the resources of the coastal seas, and a number of specific actions are set out in Agenda 21. But action is still not being taken on a scale which matches the problem. There are four probable reasons: first, the sea is still assumed to be too big to damage; second, jurisdiction is inadequate; third, serious national and international conflicts of interest remain; and fourth, economic distortions hamper sound judgement. The northern seas, which suffer less from these problems, should be demonstration areas for sound marine resource management. 相似文献
14.
Todd EC 《Marine pollution bulletin》2006,53(10-12):569-578
Surveillance systems for foodborne disease vary in capacity by country, especially for marine-related illnesses. Generally, the more developed the country is, the more funding that is put into its surveillance programs, but no country has an outstanding system that could serve as a model for all others. An additional problem is lack of consistency. Approaches to surveillance and available resources change over time, so that apparent trends may reflect more of an administrative function. Most countries have some passive system that allows data on foodborne illnesses to be sent to centralized authorities where summaries are generated. However, these depend on the uneven quality of the source data that vary according to the resources allocated at the local level. Active surveillance systems collect data targeted to answer specific epidemiological questions more efficiently, but at such a high cost that most countries do not have the resources, except on a occasional basis. There is also the issue of what to do with the collected data. There has to be a conscious effort to translate the problems identified from the surveillance programs to consider strategies for prevention and control of foodborne disease. Otherwise, there is little value in having these kinds of monitoring programs. Another problem is lack of coordination in surveillance systems between most countries, so that information can be rapidly and efficiently shared. That being said, surveillance over the years had generated much interesting information on how disease agents are transmitted through the food supply, and where contamination and growth by pathogens in the food production and preparation chain typically occur. In addition, attempts are being made to create regional networks in different parts of the world usually initiated by organizations like WHO and PAHO. The kinds of information collected and programs being introduced are discussed in examples taken from both the developed and less developed world, followed by a series of recommendations for improving surveillance on a global basis. A recent burden in the surveillance system is the potential for a deliberate attack on the food supply with agents not usually involved with foodborne illness. At least in the US, a major concern is for the rapid detection and containment of a massive contamination of the food supply. 相似文献
15.
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
16.
《Marine pollution bulletin》2007,54(10-12):569-578
Surveillance systems for foodborne disease vary in capacity by country, especially for marine-related illnesses. Generally, the more developed the country is, the more funding that is put into its surveillance programs, but no country has an outstanding system that could serve as a model for all others. An additional problem is lack of consistency. Approaches to surveillance and available resources change over time, so that apparent trends may reflect more of an administrative function. Most countries have some passive system that allows data on foodborne illnesses to be sent to centralized authorities where summaries are generated. However, these depend on the uneven quality of the source data that vary according to the resources allocated at the local level. Active surveillance systems collect data targeted to answer specific epidemiological questions more efficiently, but at such a high cost that most countries do not have the resources, except on a occasional basis. There is also the issue of what to do with the collected data. There has to be a conscious effort to translate the problems identified from the surveillance programs to consider strategies for prevention and control of foodborne disease. Otherwise, there is little value in having these kinds of monitoring programs. Another problem is lack of coordination in surveillance systems between most countries, so that information can be rapidly and efficiently shared. That being said, surveillance over the years had generated much interesting information on how disease agents are transmitted through the food supply, and where contamination and growth by pathogens in the food production and preparation chain typically occur. In addition, attempts are being made to create regional networks in different parts of the world usually initiated by organizations like WHO and PAHO. The kinds of information collected and programs being introduced are discussed in examples taken from both the developed and less developed world, followed by a series of recommendations for improving surveillance on a global basis. A recent burden in the surveillance system is the potential for a deliberate attack on the food supply with agents not usually involved with foodborne illness. At least in the US, a major concern is for the rapid detection and containment of a massive contamination of the food supply. 相似文献
17.
The Ter Vell (NE Iberian Peninsula) is a eutrophic coastal lagoon which has been flooded by the excess irrigation water and the agricultural runoff during the last decades. Between 1999 and 2003, restoration measures were applied to improve its water quality. At the same time, but independently, agricultural water management drastically reduced the freshwater inflow. The short-term effects of these management actions on the limnological characteristics of the lagoon were analysed by comparing two hydrological cycles, one before (1999/2000) and the other one after (2002/2003) the actions. The two cycles are illustrative of opposite situations in the hydrological functioning of coastal wetlands. In the first, the lagoon was exorheic, with prolonged flooding periods and a low residence time; in the second, it had a more endorheic character, with scarce water inputs and prolonged periods of confinement. Consequently, nitrogen inputs diminished and organic load and salinity increased as the internal loading and the accumulation effects became more relevant. These effects were actually caused by the drastic reduction in the freshwater inflow which prevented, in turn, the success of the restoration measures. The zooplankton community of the Ter Vell lagoon was not significantly altered by the hydrological change, at least in the short-term, and rotifers and cladocerans, mainly those species indicative of eutrophy, dominated the community. 相似文献
18.
Over recent decades, research has been directed to assessing the impacts of land uses on valuable natural assets, such as the Great Barrier Reef. Land managers in adjacent areas are expected to adopt practices to minimize any adverse affects on downstream environments. Conversely, researchers are being pressed to provide answers to the problems. In response, researchers and environmental managers are bombarding land managers with information regarding the potential environmental implications of their practices. Is this an effective mode to achieve on-ground change?
Collaboration between all groups – research, industry and extension – may be more effective in developing and implementing practical solutions to these more complex issues. A change from the research and extension models currently used may be needed to achieve positive resource management outcomes.
Research, development and extension initiatives underway in the Australian sugar industry to improve farm practice and reduce the potential for adverse impacts on downstream environments are discussed. Case studies provide some insights into how science and extension skills work best together and how an industry group can respond to a community concern. 相似文献
19.
Quantifying water vulnerability: a multi-dimensional approach 总被引：2，自引：0，他引：2
Caroline A. Sullivan 《Stochastic Environmental Research and Risk Assessment (SERRA)》2011,25(4):627-640
In today’s uncertain world, vulnerability of water supplies is of increasing concern. A number of factors influence this,
ranging from physical conditions through to human management capacities. Across the Orange River Basin in southern Africa,
these threats arise from overpopulation and farming pressure, with agrochemical and industrial runoff as well as harsh weather
conditions giving rise to severe problems of erosion and land degradation. Under conditions of climate change, these threats
are exacerbated, as temperature rises and water resources become more erratic. Since water is both an essential instrument
of livelihood support and a crucial factor of production, there is a need to develop more effective mechanisms to identify
those areas where its scarcity or poor management can bring about a slowdown in the development process. This urgency is heightened
by the international commitment to the Millennium Development Goals (MDGs), supposedly to be reached by 2015. In addition
to the MDGs, governments are also committed to the development of basin management plans for Integrated Water Resources Management (IWRM). This means that, in order to try to allocate water in an equitable and efficient way, better understanding is needed
of all of the complexities of managing water across heterogeneous basins. It is now recognized that effective water management
is much more dependent on effective governance than on hydrologic regimes. Ranging from traditional local customary norms
and practices dating back through generations to the latest state-of-the-art science-based international agreements, water
governance is a key to supporting the lives and livelihoods of local populations. Access to information is an essential feature
of any of these approaches, and harmonization of data on water issues is long overdue. This paper provides an outline of an
index-based methodology on which an assessment of water vulnerability can be made. In this approach, supply-driven vulnerability (from water systems) and the demand-driven vulnerability (from water users), are evaluated at the municipal scale. By combining these various dimensions together mathematically,
a Water Vulnerability Index (WVI) can be generated. 相似文献
20.
The coast of Honduras, Central America, represents the southern end of the Mesoamerican Barrier Reef System, although its marine resources are less extensive and studied than nearby Belize and Mexico. However, the coastal zone contains mainland reef formations, mangroves, wetlands, seagrass beds and extensive fringing reefs around its offshore islands, and has a key role in the economy of the country. Like most tropical areas, this complex of benthic habitats experiences limited annual variation in climatic and oceanographic conditions but seasonal and occasional conditions, particularly coral bleaching and hurricanes, are important influences. The effects of stochastic factors on the country's coral reefs were clearly demonstrated during 1998 when Honduras experienced a major hurricane and bleaching event. Any natural or anthropogenic impacts on reef health will inevitably affect other countries in Latin America, and vice versa, since the marine resources are linked via currents and the functioning of the system transcends political boundaries. Much further work on, for example, movement of larvae and transfer of pollutants is required to delineate the full extent of these links.
Anthropogenic impacts, largely driven by the increasing population and proportion of people living in coastal areas, are numerous and include key factors such as agricultural run-off, over-fishing, urban and industrial pollution (particularly sewage) and infrastructure development. Many of these threats act synergistically and, for example, poor watershed management via shifting cultivation, increases sedimentation and pesticide run-off onto coral reefs, which increases stress to corals already affected by decreasing water quality and coral bleaching. Threats from agriculture and fishing are particularly significant because of the size of both industries. The desire to generate urgently required revenue within Honduras has also led to increased tourism which provides an over-arching stress to marine resources since most tourists spend time in the coastal zone. Hence the last decade has seen a dramatic increase in coastal development, a greater requirement for sewage treatment and more demand for freshwater, particularly in the Bay Islands.
Although coastal zone management is relatively recent in Honduras, it is gaining momentum from both large-scale initiatives, such as the Ministry of Tourism's ‘Bay Islands Environmental Management Project', and national and international NGO projects. For example, a series of marine protected areas and legislative regulations have been established, but management capacity, enforcement and monitoring are limited by funding, expertise and training. Existing and future initiatives, supported by increased political will and environmental awareness of stakeholders, are vital for the long-term economic development of the country. 相似文献