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1.
The history and rationale of environmental regulation with respect to nutrient emissions from Danish agriculture is briefly outlined, while the current regulation is detailed through reference to and statement of actual paragraphs in statutory orders. The present regulations mainly concern nitrogen losses in the form of farm waste discharges, ammonia volatilization from animal manure and nitrate leaching from agricultural land. Being an important nutrient, phosphorus is only considered implicitly in the regulations. The main elements of the regulations include provisions for storage capacity of animal manure, livestock density on a farm basis, and mandatory submission of fertilizer and crop rotation plans to the authorities. The fertilizer plans and the resulting agricultural practices with respect to the use of both commercial fertilizers and animal manures must comply with normative fertilizer values, stated as a function of the yield expectation of agricultural crops, and minimum utilization efficiencies of animal manure. It is thus a violation of Danish laws and regulations to apply more fertilizer than indicated by the normative values in the statutory orders (and violation of the provisions may be punished by fines). The current regulations apply advisory and regulatory instruments. Financial instruments are not used. It is therefore important that where aspects of the common agricultural policy have a potential to reduce nutrient emissions, this potential is used to the full.  相似文献   

2.
3.
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   

4.
Poland largely encompases the estuary of the Vistula and Odra rivers, which drain into the Baltic Sea. Only a very small area of the south-east part of the country is within the Black Sea Basin. Poland contributes significantly to the pollution of the Baltic Sea, with biogenic nutrients and organic substances. Poland includes more than half the coastal inhabitants of the Baltic Sea, and they use 40% of the arable land situated there. The contribution to the pollution of this sea with nitrogen, phosphorus and organic substances is approximately 30, 40 and 22%, respectively. The main sources of nutrients are untreated sewage and the runoff and leakage of fertilizers from agricultural land. The natural conditions in Poland are poorer than in Western Europe due to the prevalence of light soils and a short growing period with frequent droughts. After correcting the synthetic index for soil and climate, it was estimated that for each inhabitant of Poland there are 0.3 ha of farmland, which is comparable to that of Western Europe. For the maintenance of the population, intensive agricultural production must be accompanied by environmental protection regulations. Polish agriculture is not only a polluter but also a recipient of pollution, especially the deposits of sulphur and heavy metals emitted by industry and municipal areas. The estimated annual emission of sulphur dioxide is about 4 million t, which equals an average deposit of about 90 kg of sulphur per hectare of farmland. The pedological processes and acid deposits cause more than 60% of agricultural land in Poland to be acidic. The contamination of soils with heavy metals in general is lower than in Western Europe, but in some areas (e.g. Upper Silesia) it exceeds the safe limits.  相似文献   

5.
Nutrient loads from the land to the sea must be reduced to combat coastal eutrophication. It has been suggested that further mitigation efforts are needed in the brackish Baltic Sea to decrease nutrients, especially in eutrophic coastal areas. Mussel farming is a potential measure to remove nutrients directly from the sea. Mussels consume phytoplankton containing nitrogen (N) and phosphorus (P); when the mussels are harvested these nutrients are removed from the aquatic system. However, sedimentation of organic material in faeces and pseudo-faeces below a mussel farm consumes oxygen and can lead to hypoxic or even anoxic sediments causing an increased sediment release of ammonium and phosphate. Moreover, N losses from denitrification can be reduced due to low oxygen and reduced numbers of bioturbating organisms. To reveal if mussel farming is a cost-effective mitigation measure in the Baltic Sea the potential for enhanced sediment nutrient release must be assessed.  相似文献   

6.
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   

7.
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   

8.
《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   

9.
The herbicides atrazine, simazine and terbuthylazine (and the degradation product deethylatrazine) were analysed in two river-to-open-sea transects and two vertical (open-sea) profiles in the southern Baltic off Poland. Samples taken in September 1995 and April 1997 contained total triazine concentrations ranging from 7 to 31 and 4.5 to 13 ng/dm3, respectively. Concentrations of the individual compounds ranged from 0 to 8 ng/dm3. These are generally higher than levels reported, for example, in the North Sea. The largest surface concentrations were found close to the Vistula and Odra river mouths, endorsing river run-off as a primary source of the triazines. Temporal variability can be related to the late-spring and early-summer agricultural applications of the compounds. Variations in ratios between the individual triazines can be explained by usage patterns and differing residence times. Offshore vertical profiles indicate enrichment of the surface layer through atmospheric triazines inputs, highest concentrations above the halocline associated with colloidal organics and lowest concentrations in the bottom waters, probably as a result of particulate scavenging. The influence of the North Sea inflow to the Baltic is also discussed.  相似文献   

10.
Socio-economic development in Europe has exerted increasing pressure on the marine environment. Eutrophication, caused by nutrient enrichment, is evident in regions of all European seas. Its severity varies but has, in places, adversely impacted socio-economic activities. This paper aims to evaluate the effectiveness of recently adopted policies to reduce anthropogenic nutrient inputs to European seas. Nitrogen and phosphorus budgets were constructed for three different periods (prior to severe eutrophication, during severe eutrophication and contemporary) to capture changes in the relative importance of different nutrient sources in four European seas suffering from eutrophication (Baltic Proper, coastal North Sea, Northern Adriatic and North-Western Black Sea Shelf). Policy success is evident for point sources, notably for P in the Baltic and North Seas, but reduction of diffuse sources has been more problematic.  相似文献   

11.
One of the key environmental concerns about shrimp farming is the discharge of waters with high levels of nutrients and suspended solids into adjacent waterways. In this paper we synthesize the results of our multidisciplinary research linking ecological processes in intensive shrimp ponds with their downstream impacts in tidal, mangrove-lined creeks. The incorporation of process measurements and bioindicators, in addition to water quality measurements, improved our understanding of the effect of shrimp farm discharges on the ecological health of the receiving water bodies. Changes in water quality parameters were an oversimplification of the ecological effects of water discharges, and use of key measures including primary production rates, phytoplankton responses to nutrients, community shifts in zooplankton and delta15N ratios in marine plants have the potential to provide more integrated and robust measures. Ultimately, reduction in nutrient discharges is most likely to ensure the future sustainability of the industry.  相似文献   

12.
Recent oceanographic observations and a retrospective analysis of nutrients and hydrography over the past five decades have revealed that the principal source of nutrients to the Gulf of Maine, the deep, nutrient-rich continental slope waters that enter at depth through the Northeast Channel, may have become less important to the Gulf's nutrient load. Since the 1970s, the deeper waters in the interior Gulf of Maine (>100 m) have become fresher and cooler, with lower nitrate (NO3) but higher silicate (Si(OH)4) concentrations. Prior to this decade, nitrate concentrations in the Gulf normally exceeded silicate by 4–5 μM, but now silicate and nitrate are nearly equal. These changes only partially correspond with that expected from deep slope water fluxes correlated with the North Atlantic Oscillation, and are opposite to patterns in freshwater discharges from the major rivers in the region. We suggest that accelerated melting in the Arctic and concomitant freshening of the Labrador Sea in recent decades have likely increased the equatorward baroclinic transport of the inner limb of the Labrador Current that flows over the broad continental shelf from the Grand Banks of Newfoundland to the Gulf of Maine. That current system now brings a greater fraction of colder and fresher deep shelf waters into the Gulf than warmer and saltier offshore slope waters which were previously thought to dominate the flux of nutrients. Those deep shelf waters reflect nitrate losses from sediment denitrification and silicate accumulations from rivers and in situ regeneration, which together are altering the nutrient regime and potentially the structure of the planktonic ecosystem.  相似文献   

13.
In order to determine and assess their status sediments from the German coastal waters of the baltic sea were analyzed for structural parameters and for several groups of harmful substances. Regarding all groups of harmful substances, i.e. nutrients, heavy metals and organic toxicants the sediments of the eastern sections investigated (Strelasund, Peenestrom and Stettin Lagoon) are generally more polluted than the sediments of the other ones.The sediments of the examined sections of the Baltic coast compare with North Sea sediments by factors of between 0.05 and 4 with regard to heavy metals.Because of the variability of the concentration of harmful substances in the various coastal sections, it is imperative to make a differentiated assessment of the polluted sediments and to set district-related targets for the various sections of the Baltic coast.  相似文献   

14.
We present and analyse a fully coupled physical–biogeochemical model of the uptake and release of carbon dioxide in the Baltic Sea. The modelling includes the interaction between physical (stratification, temperature, salinity, penetration of solar radiation, and ice), chemical (total alkalinity, pH, dissolved inorganic carbon, oxygen, and nutrients), and biological processes (plankton and dissolved organic carbon (DOC)). These processes have been built into an advanced process-oriented coupled basin ocean model that has been extensively explored and validated for the Baltic Sea.  相似文献   

15.
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   

16.
The need to assess the environmental status of marine and coastal waters according to the EU Water Framework Directive (WFD) encouraged the design of specific biotic indices to evaluate the response of benthic communities to human-induced changes in water quality. In the present study three of these indices, the traditional Shannon Wiener Index (H') and the more recently published AMBI (AZTI' Marine Biotic Index) and BQI (Benthic Quality Index), were tested along a salinity gradient in the southern Baltic Sea. The comparison of the three indices demonstrates that in the southern Baltic Sea the ecological quality (EcoQ) classification based on macrozoobenthic communities as indicator greatly depends on the biotic index chosen. We found a significant positive relation between species number, H', BQI and salinity resulting in EcoQ status of "Bad", "Poor" or "Moderate" in areas with a salinity value below 10 psu. The AMBI was less dependent on salinity but appear to partly overestimate the EcoQ status. Presently none of these biotic indices appear to be adjusted for application in a gradient system as given in the southern Baltic Sea. A potential approach describing how to overcome this limitation is discussed.  相似文献   

17.
The drainage channel network in Vojvodina,northern part of the Republic of Serbia,in total length of around 20,000 km,transfers excessive(under)ground waters from around 2.15 million ha of lowlands.Channels are mostly in direct connection with the surrounding arable agricultural land and are exposed to different run-off,leaching and/or wind erosion processes.Close to urban areas,some channel sections serve as recipients of unrefined sewage and industrial waste waters.Water flows and velocities,as well as the transportable capacity of fluvial materials(sediments) are relatively low.This,in combination with other natural and anthropogenic impacts,contributes to sediment generation in the drainage channel network.Based on around 100 sediment samples from 46 channels,concentrations of primary nutrients(N,P and K) were elaborated in this study.Detected concentrations of macronutrients in the channel sediments(e.g.N 1-1.2%,P 100-265 and K 100-380 mg 100 g~(-1)) exceeded their content in surrounding arable land by a few fold.Also,significantly higher nutrient concentrations(in average by 50%) were detected in downstream(vs.upstream) channel sections.An excessive presence of observed elements in channel sediments,due to interactive processes between water and sediment material,can adversely influence the water quality and life conditions for channel biota and caused other negative environmental impacts such as eutrophication.These results clearly confirm that the processes of nutrient accumulation in channel sediments are greater than those in the surrounding,mostly intensively arable land areas.The erosion of unprotected agricultural areas and sediment transport as the most important pollution pathways from the drainage basin to channel network may be essential factors responsible for detected condition of nutrient accumulation.  相似文献   

18.
The nutrient load on the Gulf of Finland, the Baltic Sea, is estimated taking into account the export of nutrients from Lake Ladoga with Neva runoff, from the Chudsko-Pskovskoe Lake with Narva runoff, from a partial watershed of the Gulf of Finland, and wastewater discharges from St. Petersburg. The data used include the materials of state monitoring of water bodies and state statistical reports on northwestern Russia, materials of GUP Vodokanal Sankt Peterburga, the results of earlier researches of water quality formation in Lake Ladoga, the Gulf of Finland, and on their catchment, and the results of calculation of nutrient load on the gulf with the use of a model developed in the Institute of Limnology, RAS. Currently, the annual nutrient load on the Gulf of Finland is ∼5200 t Ptot and 70800 t Ntot. The phosphorus load exceeds the admissible levels recommended by the Helsinki Commission, thus suggesting the need to search for real ways to reduce the load in the future.  相似文献   

19.
The most serious environmental problem encountered in the Baltic Sea is eutrophication. Finland finalised in spring 2002 its national Programme for the Protection of the Baltic Sea. The programme contains more than 30 measures for improving the state of the Baltic Sea and protecting the marine environment. Total national investments during the next 10-15 years will amount to EUR 300-370 million. The highest annual cost will be environmental support to agriculture. The bulk of the rest of the money will be used for nitrogen purification of municipal wastewater, improvement of water protection in dispersed settlement areas, and investments to improve maritime safety and decrease the risks of oil spills.  相似文献   

20.
The atmospheric chemistry and deposition model has been applied for calculation of nitrogen and sulphur depositions to the entire North Sea area for the year 1999. The total atmospheric nitrogen and sulphur depositions to the North Sea area were determined to 709 kton (kt) N and 551 kt S, respectively. Since the North Sea area was calculated to be 747,988 km2, this is equivalent to an average deposition of 0.9 ton N km?2 and 0.7 ton S km?2, respectively. The depositions decrease strongly from the south end (about 2–3 kt N km?2) to the north end (about 0.2 kt N km?2) of the North Sea, due to increasing distance to the large source areas in the northern part of the European continent. The territorial waters of Belgium, the Netherlands and Germany receive about 50% higher deposition densities than the average value for the entire North Sea area. For the remaining territorial waters of the North Sea the depositions follow more or less the fraction of the area. The results furthermore show that about 60% of the total nitrogen deposition is related to emissions from combustion sources (nitrogen oxides) and about 40% from emissions related to agricultural activities (ammonia).  相似文献   

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