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1.
The environmental policies aimed at reducing nutrient emissions from the agricultural sectors in the Baltic states, Poland, Germany and Scandinavia are detailed. The emissions include leaching, run-off and erosion losses of nitrogen and phosphorus, volatile losses of ammonia, and farm waste discharges. Farm waste discharges and nitrate leaching from agricultural fields have received considerable attention during the last few decades, but more recently the remaining loss categories have also been recognized as substantial contributors of nutrients to the environment.

Environmental targets have been set in the Helsinki Commission (HELCOM) Ministerial Declaration of 15 February 1988, stating that a significant reduction (e.g. 50%) of the nutrient load to the Baltic Sea shall be reached before 1995. A similar target for the Oslo and Paris (OSPARCOM) Convention waters has been set by the North Sea ministers, while the EU Nitrate Directive expresses an environmental standard by setting an upper limit to nitrate concentrations in groundwater.

It is argued here that in most instances only marginal reductions in agricultural emissions will be achieved under the current policies before 1995 (or later). Exceptions are seen in transition economy countries where fertilizer consumption and livestock production have decreased significantly. As agriculture is a major source of nutrients to convention waters, the overall 50% reduction target will not be met. Furthermore, it is argued that there is scope for a considerable reduction of losses from agriculture and that the instruments to achieve the objectives are readily available. Measures should focus on the total input of nutrients to the agro-ecosystems and not so much attempt to regulate specific management practices. The more prominent instruments include the reduction or alteration of agricultural subsidies, market considerations and the use of environmental taxes (on fertilizers and nutrients in animal manure) combined with in-depth structural regulations. It is, however, necessary to generate further political willingness to ensure decisions and successful implementation of the various measures—a process which requires public attention.  相似文献   


2.
The Helsinki Commission (HELCOM) Baltic Sea Action Plan, adopted by the coastal countries of the Baltic Sea and the European Community in November 2007, is a regional intergovernmental programme of measures for the protection and management of the marine environment explicitly based on the Ecosystem Approach. The Action Plan is structured around a set of Ecological Objectives used to define indicators and targets, including effect-based nutrient input ceilings, and to monitor implementation. The Action Plan strongly links Baltic marine environmental concerns to important socio-economic fields such as agriculture and fisheries and promotes cross-sectoral tools including marine spatial planning. Due to complementarities with the European Union (EU) Marine Strategy Framework Directive, the Action Plan is in essence a pilot for this process without neglecting the important role of the Russian Federation - the only Baltic coastal country not a member of the EU.  相似文献   

3.
Concerning increased degradation of marine ecosystems, there is a great political and institutional demand for an array of different tools to restore a good environmental status. Thereby, eutrophication is acknowledged as one of the major human induced stressors which has to be monitored and reduced. The present study concentrates on an assessment of the eutrophication status of the Baltic Sea Protected Areas by use of available data and GIS technologies. Two geodata layers were used for analysis: (1) a map on the eutrophication status of the Baltic Sea generated by the Helsinki Commission applying the HELCOM Eutrophication Assessment Tool (HEAT), and (2) modelled data on atmospheric nitrogen deposition made available by the European Monitoring and Evaluation Programme (EMEP). The results yielded comprehensive and conclusive data indicating that most of the BSPAs may be classified as being 'affected by eutrophication' and underlining the need to decrease the overall emissions of nutrients.  相似文献   

4.
《Marine pollution bulletin》2012,64(5-12):209-214
Concerning increased degradation of marine ecosystems, there is a great political and institutional demand for an array of different tools to restore a good environmental status. Thereby, eutrophication is acknowledged as one of the major human induced stressors which has to be monitored and reduced. The present study concentrates on an assessment of the eutrophication status of the Baltic Sea Protected Areas by use of available data and GIS technologies. Two geodata layers were used for analysis: (1) a map on the eutrophication status of the Baltic Sea generated by the Helsinki Commission applying the HELCOM Eutrophication Assessment Tool (HEAT), and (2) modelled data on atmospheric nitrogen deposition made available by the European Monitoring and Evaluation Programme (EMEP). The results yielded comprehensive and conclusive data indicating that most of the BSPAs may be classified as being ‘affected by eutrophication’ and underlining the need to decrease the overall emissions of nutrients.  相似文献   

5.
The legislative framework for the environmental protection of the North Sea has developed extensively during the past two decades. This framework includes proposals within national, regional, European and global initiatives. This paper describes the development of the Oslo and Paris Commissions and their relationship with the North Sea Ministerial Conferences. The new OSPAR Convention, signed in Paris in 1992, is described as a model for protection frameworks for other regional seas.  相似文献   

6.
Protection of the sea has received much political attention—for example, at successive North Sea Conferences environmental ministers have formulated a stringent policy with the aim of reducing pollution in the north-east Atlantic. In the past this area received many substances from many sources, but gradually intergovernmental action since 1972 in the Oslo and Paris Conventions has succeeded in tracing the major sources and understanding the effects of these inputs on the marine environment. After long discussion, many dumpings and discharges have been ended because they were considered harmful to the marine environment. Dredging activities were included in the discussions but they may be regarded as being a special case compared with many other disposals.

In general, clean dredged material for sea disposal offers no problems, although restrictions may be caused by physical impacts, mainly to habitats for living organisms. However, this material also has positive, often even beneficial uses. In contrast, contaminated material disposal is restricted and the internationally accepted rule is that the material should not create hazards to human health, harm living resources and marine life or damage amenities or interfere with other legitimate uses of the sea. There are in principle three options for dealing with polluted sediments: doing nothing, remedial action in situ, removal of the contaminated material; occasionally treatment is a possibility. The distinction has been made between the disposal of industrial waste, sewage sludge or dredged material. Industrial waste disposal is now prohibited; sewage sludge may be dumped until 31 December 1998, although dredged material may still be stored at sea under certain conditions. The Oslo Convention 1972 decided with regard to dredged material: that pollution has to be tackled at the source; dumping at sea is forbidden, although dredged materials may be excluded from this; land disposal prevails, although in several countries there is a growing resistance to disposal on land; there should be a precautionary approach against marine disposal; a stand-still principle should be followed where the quantities disposed in a certain year should not be exceeded nor should the quality of the receiving water be reduced; marine disposal should be phased out and, where appropriate, time-limits set; and the polluter pays.

Dredged material is regarded as polluted and as a consequence may in general not be disposed of at sea when it contains substances listed in the Annexes of the Convention. Exceptions to this are indicated by the terms ‘a trace contaminant’, ‘rapidly rendered harmless’ or ‘significant amounts’. Therefore, to achieve uniformity in the application of the Convention, guidelines have been prepared by a joint London Dumping Convention/Oslo Commission working group of experts on dredged material. Several characteristics must be considered when choosing a site for marine disposal and interests such as beach recreation, sport and commercial fishing, nature, cultural or historical interests, navigation, military interests and cables and pipelines should be taken into account. Also the capacity of the area to assimilate disposed matter per time unit must not be exceeded, especially in low energy areas. It is considered that in discussions of the environmental aspects of dredging it is important that associations such as PIANC argue for safe and economic navigation.  相似文献   


7.
The main focus of this work was to evaluate the capabilities of information technology to establish the biological activity of organic xenobiotics on the example of hazardous substances from the list of Helsinki commission (HELCOM) aimed at protecting the marine environment of the Baltic Sea from negative impact. These methodological approaches will be used in future for the preliminary assessment of the toxicity of new xenobiotics revealed in Baltic waters.  相似文献   

8.
Loading by atmosphere and by the Baltic Sea cause gravity change at Metsähovi, located 15 km from the open sea. Gravity is changed by both the Newtonian attraction of the loading mass and by the crustal deformation. We have performed loading calculations using appropriate Green's function for both gravity and deformation, for both atmospheric and Baltic loading. The loading by atmosphere has been computed using a detailed surface pressure field from high resolution limited area model (HIRLAM) for north Europe up to 10° distances. Baltic Sea level is modelled using tide gauge records. Calculations show that 1 m of uniform layer of water corresponds to 31 nm s−2 in gravity and −11 mm in height. Modelled loading is compared with observations of the superconducting gravimeter T020 for years 1994–2002. The combination of HIRLAM and a tide gauge record decreases RMS of gravity residuals by 14% compared to single admittance in air pressure corrections without sea level data. Regression of gravity residuals on the tide gauge record at Helsinki (at 30 km distance) gives a gravity effect of 26 nm s−2 m−1 for Baltic loading.The gravity station is co-located with a permanent GPS station. We have also associated the loading effects of the atmosphere and of the Baltic Sea with temporal height variations. The range of modelled vertical motion due to air pressure was 46 mm and that due to sea level 18 mm. The total range was 38 mm. The effects of the Baltic Sea and of the atmosphere partly cancel each other, since at longer periods the inverse barometer assumption is valid. Regression of the modelled height on local air pressure gives −0.37 mm hPa−1, corresponding approximately to width 6° for pressure system.We have tested the models using one year of daily GPS data. Multilinear regression on local air pressure and sea level in Helsinki gives the coefficient −0.34 mm hPa−1 for pressure, and −11 mm m−1 for sea level. These match model values. Loading by air pressure and Baltic Sea explains nearly 40% of the variance of daily GPS height solutions.  相似文献   

9.
Four watersheds, each characterized by a major resource use were selected for the study: The Vistula River in Poland—agriculture; the Dalälven River in Sweden—forestry; the Archipelago Sea in Sweden, Finland, Estonia—tourism; and the Lake Peipsi in Estonia/Russia—fisheries/agriculture. The main objective was to examine the reactions of particular ecosystems within the Baltic Sea drainage area, and to assess sustainability conditions on the regional level.The degree of sustainability and impact on the Baltic Sea were investigated through workshops and seminars in the areas. Overviews of environmental and socio-economic conditions were succinctly summarized in commissioned papers. Interventions by and discussions with scholars, sector experts, administrators and stakeholders of the various sites laid the foundation for conceptualizing the interaction of natural and human forces for each case. The project was able to draw quite a number of conclusions, summarized as the following lessons learnt.In the Vistula Region, nutrient emissions have levelled off but shortage of freshwater is critical. Forestry in the Dalälven watershed is largely environmental-friendly, except for fragmentation of the landscape and its negative impact on biodiversity. In the Archipelago area a former low-energy community has been replaced by a leisure time society. Different types of tourism is developing, but despite this variety, an improved integration of ecological properties with socio-economic patterns is required in order to build a sustainable, living Archipelago. The lake Peipsi basin and the surrounding area suffer both from problems of resource management and economic backwardness. Parts of the local economy has lost access to the one time large Soviet market, although the Estonian side has apparently benefited from present economic growth. To cope with the division of the lake, a regime for trans-national management is unfolding. It is based on both informal and, to an increasing extent, agreed professional contacts.Networks of engaged people were in all sites a resource for and promoter of the sustainability path. In order to succeed and to maintain the zeal, they need strong institutional support and common goals. Public programmes in the Baltic, ie. the work of the Helsinki Commission and Baltic Agenda 21, have developed instruments to enhance sustainability beneficial for the management of these watersheds. But critical tasks remain to be done in developing a shared understanding of ways to improve management of ecosystems with social factors.  相似文献   

10.
The loading effect of the Baltic Sea is immediately recognizable in the gravity record of the superconducting gravimeter T020 in Metsähovi, Finland, by simply inspecting residual gravity together with the tide gauge record at Helsinki 30 km away. The station is 10 km from the nearest bay of the Baltic Sea and 15 km from the open sea. Sea level variations in the Baltic are non-tidal and driven at short periods primarily by wind stress, at longer periods by water exchange through the Danish straits. Locally they can have a range of 2–3 m. Loading calculations show that a uniform layer of water covering the complete Baltic Sea increases the gravity in Metsähovi by 31 nm/s2 per 1 m of water, and the vertical deformation is −11 mm. The observed gravity response to the local sea level is generally less, since the variations at short periods are far from uniform areally, the same water volume just being redistributed to different places. Regression of the whole gravity record (1994-2001) on local sea level gives 50–70% of the uniform layer response, as do loading calculations using actual water distributions derived from 11 tide gauges. However, both fits are dominated by some extreme values of short duration, and parts of the gravity record with long-period variations in sea level are close to the uniform layer response. The gravity observations can be used to test corrections for other co-located geodetic observations (GPS, satellite laser ranging) which are influenced by the load effect but not sensitive enough to discriminate between models.  相似文献   

11.
The discharge of nutrients is investigated in relation to their sources and effects in two case studies. The reduction of 47% in the phosphorus load from Denmark to marine areas between 1989 and 1993 has resulted in significantly lower phosphorus concentrations in most Danish coastal waters, and tendency to decrease can be seen in the Belt Sea and Kattegat as well. No general changes in nitrogen concentrations have been observed. This is due to the fact that more than 80% of the nitrogen load in Danish waters originate from diffuse agricultural sources.In the Pomeranian Bight strong nutrient gradients are generated by the mixing of Odra river water and coastal water. The spreading of the river plume could be exactly observed especially in winter, when biological activity is low. In general, different types of distribution, transport and modification patterns can be described.The annual input of nutrients from the catchment area to the Baltic Sea was estimated to be around 1000 kt N and 46 kt P. As a result, winter concentrations of phosphate and nitrate are characterized by positive overall trends in the surface layer in all subregions of the Baltic Proper for the period 1969 to 1993. These trends stem mainly from the strong increase in the 1970ies and early 1980ies. Thereafter, the concentrations of both nutrients fluctuate strongly around a high level. The drastic decrease in fertilizer consumption since the late 1980ies mainly caused by the great economic changes in the countries of the former East Bloc is not yet significantly reflected in decreasing winter concentrations, but first signs already have been found in the decrease in averaged phosphate concentrations in winter, especially in the Arkona and Bornholm Seas.  相似文献   

12.
13.
Over the years many policy measures have been taken to prevent illegal oil discharges from ships, like the MARPOL 73/78 Convention (1983) and the Bonn Agreement (1969/1983). However, the number of discharges remained high, leading to chronic oiling of seabirds and sensitive coastlines, therefore further measures were taken. The aim of this study is to quantify the effectiveness of two key legislative regulations: the IMO-designation of the North Sea as MARPOL Special Area which took effect in 1999, and the adoption of the EU Directive on Port Reception Facilities in 2000. Under study is the heavily navigated Belgian Surveillance Area, monitored since 1991, characterised by shallow waters with ecologically important sandbanks. The aerial surveillance data from 1991 to 2010 show a stepwise decrease in ship-source oil pollution. Three time periods can be distinguished with two turning points coinciding with the actual implementation of these key legislative measures, confirming their effectiveness.  相似文献   

14.
The paper presents a theoretical study to explain the regular occurrence of a cold water upwelling cell at the southern east coast of the Gotland island in the central Baltic Sea. While for a circular island up- and downwelling patterns would rotate around the island, the responses around the elongated Gotland island with narrow tips at its southern and northern ends are different. The study uses the example of the response of a coastal ocean to a wind band to develop an understanding of important aspects of generation of Kelvin waves and how the waves change the response patterns.  相似文献   

15.
Politics, economics and science interpret the concept of sustainability differently. The discussion distinguishes between economic, environmental and social sustainability. While advocates of economic sustainability assume that natural capital is substitutable by humanmade capital, policies for a sustainable development are questionable. The paper therefore highlights a regional case to show that sustainability is indivisible. Moreover, economics and policies serving Baltic sustainability need a new institutional network to manage the multispecies resource with participation of the social players and by addressing targets step by step. The findings are based on a simple ecological-economic model providing insights for the negotiation game for all players. In addition, multispecies resource management shows a strong hierarchy in both social actions and targets. Since sustainable development is an on-going, dynamic process, policy implementation and funding must also be continuous. Sustainable development therefore challenges the institutional sets for the process and its relations to local, regional and national policies.  相似文献   

16.
Environmental impacts occur at all stages of oil and gas production. They are the result of prospecting activities, of the physical impact due to the installation of rigs, of the operational discharges when production starts and of accidental spills. The input of oil to the North Sea due to the offshore industry has been estimated at 29% of the total input of oil. The operational discharges consist of production water and drilling cuttings. An overview of statistics collected over the last 10 years shows that although the amount of oil discharged via production water is increasing as platforms are getting older, cuttings still account for 75% of the oil entering the sea as a result of normal operations. Spills represent a relatively small source of oil. The effects on the marine environment of discharges of production water and of discarded oily cuttings have been extensively studied, by national authorities as well as by the industry. Although it has not always been possible to reach consensus about the significance of the observed effects, a number of ‘agreed facts’ have led to establishment of regulations in the framework of the Paris Commission. The ‘decisions’ and ‘recommendations’ adopted by the Commission are regularly reviewed in the light of new developments.  相似文献   

17.
The western Baltic Sea infront of the German coast is a highly variable dynamical system, dominated by a complex and small-scale morphometry, the water exchange between the Baltic and North Seas, and driven by local wind. Neither data collection, nor satellite images or model simulations alone were able to explain the observed spatial patterns and transport processes. Therefore, all these methods were combined to explain the dynamical features and to systematise them according to the typical local wind pattern and time series. The aim was to develop an instrument for regional authorities which supports the interpretation of coastal water monitoring data and forms a basis for an improved monitoring strategy. Satellite data of sea surface temperature and ocean colour from the sensors NOAA-AVHRR and SeaWiFS were applied for synoptic investigations in the entire region and Landsat-7-ETM+ for regional studies. Model simulations were performed for the western Baltic using a 3D model MOM-3 and for the Szczecin Lagoon using 2D model FEMFLOW. For the first time, regional particularities in the coastal dynamical features and processes are derived for the main wind directions and for transitions between dominant wind situations west and east as derived from wind statistics. The simulated transport of particles released from different coastal and open sea sources indicate the affected areas during changing forcing conditions. The results support the interpretation of acquired coastal monitoring data as well as the assessment and optimisation of the monitoring programme.  相似文献   

18.
Globally coupled climate models are generally capable of reproducing the observed trends in the globally averaged atmospheric temperature. However, the global models do not perform as well on regional scales. Here, we present results from four 100-year, high-resolution ocean model experiments (resolution less than 1 km) for the western Baltic Sea. The forcing is taken from a regional atmospheric model and a regional ocean model, imbedded into two global greenhouse gas emission scenarios, A1B and B1, for the period of 2000 to 2100 with each two realisations. Two control runs from 1960 to 2000 are used for validation. For both scenarios, the results show a warming with an increase of 0.5–2.5 K at the sea surface and 0.7–2.8 K below 40 m. The simulations further indicate a decrease in salinity by 1.5–2 practical salinity units. The increase in water temperature leads to a prolongation of heat waves based on present-day thresholds. This amounts to a doubling or even tripling of the heat wave duration. The simulations show a decrease in inflow events (barotropic/baroclinic), which will affect the deepwater generation and ventilation of the central Baltic Sea. The high spatial resolution allows us to diagnose the inflow events and the mechanism that will cause future changes. The reduction in barotropic inflow events correlates well with the increase in westerly winds. The changes in the baroclinic inflows can be consistently explained by the reduction of calm wind periods and thus a weakening of the necessary stratification in the western Baltic Sea and the Danish Straits.  相似文献   

19.
The freshwater pearl mussel Margaritifera margaritifera (L., 1758) is considered to be a critically endangered species. It is important to obtain information on the distribution and status of the surviving populations of the species, but in Russia this work is still problematic due to the size of the country’s territory, combined with the insufficient number of available specialists. “Searching rules” have been proposed to remotely identify potential pearl mussel habitats in rivers. The most important criteria are relating to the lakes found at the rivers’ sources, as well as to the extent of the deforestation along river basins. About 200 watercourses of the Russian section of the Baltic Sea basin were evaluated using these “rules”. As a result, two previously unknown, viable populations were discovered (comprising about 53,000 specimens), while the absence of pearl mussels was made evident among some rivers which were traditionally believed to be their habitats. The obtained data provides an update on the status of pearl mussels in Russian territories located south of the 61 st degree of latitude. There are 10 populations of this species; 4 of them are almost extinct, 6 are relatively numerous but declining. The total number of pearl mussels hardly exceeds 90,000 individuals.  相似文献   

20.
Tsunami and its Hazard in the Indian and Pacific Oceans: Introduction   总被引:1,自引:0,他引:1  
The 2004 Indian Ocean tsunami caused an estimated 230,000 casualties, the worst tsunami disaster in history. A similar-sized tsunami in the Pacific Ocean, generated by the 1960 Chilean earthquake, commenced international collaborations on tsunami warning systems, and in the tsunami research community through the Tsunami Commission of International Union of Geodesy and Geophysics. The IUGG Tsunami Commission, established in 1960, has been holding the biannual International Tsunami Symposium (ITS). This volume contains selected papers mostly presented at the 22nd ITS, held in the summer of 2005. This introduction briefly summarizes the progress of tsunami and earthquake research as well as international cooperation on tsunami warning systems and the impact of the 2004 tsunami. Brief summaries of each paper are also presented.  相似文献   

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