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Environmental problems related to Europe's rivers



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Environmental problems related to Europe's rivers
There have been some remarkable improvements in recent years in the ecological status or water quality of certain European rivers such as the Rhine and the Danube. However, rivers in many parts of the Community are at risk of not reaching good ecological status or potential by 2015 due to a range of human activities. Their traditional use as recipients of effluent has had obvious negative environmental impacts. But there are other negative impacts such as 'river regulation' (irrigation, drainage, the construction of navigation channels, reservoirs, dams, etc.); damage to habitats and over-exploitation or direct impacts on species.
Status of Europe's rivers/ human pressures
The three largest European Union river basins are the Danube (817,000 km2), the Vistula (194,000 km2) and the Rhine (185,000 km2), which together drain approximately a quarter (27%) of the EU-27 territory. Europe's rivers today are used mainly for water supply, energy production, irrigation and transportation. But their use for recreational activities such as sailing, bathing and angling and other amenities is also increasingly important. The growing number of users and uses of rivers - perhaps especially around the many areas of Europe with high population densities and high industrial development - has increased the exploitive pressures on rivers, posing a risk to human health and adding to the pollution of Europe's coastal waters.
Over the past 20 years or so, according to the European Environment Agency (EEA), there have been significant advances in the treatment of sewage and industrial wastes being pumped into Europe's river systems. This has led to lower levels of most pollutants and a measurable improvement in water quality. The agricultural sector, on the other hand, has not made such good progress, as it has been under pressure to intensify to remain profitable. Nitrate levels are still as high as they were at the beginning of the last decade. High nitrate levels can result from 'runoff' carrying surplus fertiliser - which can cause eutrophication. Not only the quality of water but also the quantity available for human use is of importance, says the EEA, adding that more and more frequently there are problems with water scarcity around large cities and in southern Europe.
The main factors that increase the risk of not achieving good ecological status, or potential, in European rivers are:
• Nutrient enrichment (eutrophication) - one of the principal sources of organic pollution discharged into Europe's watercourses is from organic waste around areas of Europe with high population density and high industrial development. High levels of organic pollution tend to reduce the concentration of oxygen in water and thus affect all riverine species and habitats. Rivers with low population densities normally have reduced levels of organic pollution - for instance in Nordic countries and other mountainous areas. The agricultural sector too, with its fertilisers and manure enrichment of soil increases the concentrations of nutrients (nitrates, ammonium and phosphorus) in water that is associated with the river flow alteration (dams, reservoirs, etc) boosting the propagation of algal booms and hence water turbidity. Nevertheless, over the past 15 years the levels of organic matter concentration and nutrients in the European rivers have been gradually decreasing.
• Physical interventions including river regulation - that is the physical changes that man imposes on watercourses, such as the construction of reservoirs and energy production (hydro-electric dams), channelization and navigation structures, land drainage and irrigation, maintenance work (removal of obstacles to water flow, sediment removal, etc.). Such measures may result in a disconnection of the rivers from floodplains with a negative impact on dependent habitats and species. They may also cause disruption of the river sediment system (erosion, transport and deposition), and/or disturb aquatic organisms, for example by hindering the up- and down-stream migration of migratory fish, or by changing water flows and temperatures.
Other environmental problems affecting European rivers include:
• Acidification - decreasing of the pH levels caused by sulphur and nitrogen oxides deposition (as a result of the combustion of fossil fuels) into the rivers' catchments. This increased acidification can result in a toxic environment that has a significant negative impact on the ecosystems of rivers. Surface water acidification first became an issue of public concern in the 1970s when awareness was raised by incidences of major fish kills in the rivers and lakes in the southern most part of Norway and along the west coast of Sweden.
• Organic micro pollutants - an increased use of pesticides and the production of other organic substances has led to pollution of watercourses. Pesticides entering the aquatic environment may have serious impacts on flora and fauna and limit the use of the water for drinking water abstraction. The source of these substances is linked to agriculture and industry. While the effects of some organic chemicals are well known there are other substances where the real impact on the aquatic environment remains unclear. Minimum standards (i.e. the maximum permissible concentrations of pesticides) are regulated by Directive, in line with the revised Drinking Water Directive
• Heavy metals - the main sources in Europe's rivers are industrial and mining facilities. Concentrations of heavy metals are decreasing in European rivers and are regulated by the Water Framework Directive.
• Radioactivity - nuclear plants are normally located near water sources and thus increase the risk of contamination of the rivers by radio nuclides. The heated water released by the nuclear plant cooling systems could also have localized impacts on the river ecosystems.
Biodiversity loss
All of the above factors threaten biodiversity loss. Around 250 species of macrophytes and 250 species of fish inhabit European inland surface waters, and a significant number of birds and mammals depend on freshwater wetlands for breeding or feeding. Physical changes and water pollution have had a detrimental affect on many European freshwater habitats and resulted in the loss of their natural vegetation and animal life.
Most environmental problems concerning Europe's rivers have evolved gradually because of development pressure or lack of knowledge on how best to protect water resources. However, certain catastrophic pollution incidents such as the Sandoz disaster on the upper Rhine in 1986, as well as the more recent spillages of toxic mining waste which affected the Dohana region of Spain and the Tisza river and its tributaries in Romania, Hungary and the former Federal Republic of Yugoslavia, as well as the catastrophic floods along the rivers Danube and Elbe in 2002, have triggered action to improve river basin management on a European scale.
Rivers need to achieve good ecological status
The EU Water Framework Directive (discussed in the following section) provides an opportunity for implementing better planned, long-term water management measures that should help to minimise the impact of, or at least provide the necessary tools for, a more rapid and effective response to environmental problems in the future.
European Union Water policy
The increasing demand by Europeans for cleaner rivers (as well as lakes, groundwater and coastal beaches) was highlighted by a recent Eurobarometer opinion poll. When asked to list the five main environmental issues that Europeans were worried about, on average almost half of the EU25 respondents said they were worried about "water pollution" (47%), with figures for individual countries going up as far as 71%. This demand by Europe's citizens for sufficient quantities of good quality water for all purposes is one of the main reasons why the European Commission has made water protection one of its main priorities. The Water Framework Directive (WFD), with its overarching theme of integrated water management at the river basin level, is the operational tool for achieving the EU's goal of 'good status' for all Community waters by 2015.
Water Framework Directive (WFD)
Adopted in June 2000, the framework directive is currently in the initial phase of implementation in Member States. Involving a phased process, with strict deadlines for achieving 'good status', it sets out how water should be managed in an integrated way throughout the EU territory within river basin districts. A key element is that it obliges neighboring countries to work together to improve water quality in Pecross-border areas where they share the same river basins.
The main elements of the WFD schedule are set out below. But the most important upcoming deadline with regard to river basin planning is that by the end of 2009, Member States should have developed a management plan and a programme of measures for each river basin district, taking into account the results of studies (e.g. of the impact of human activity on the watercourses, economic analyses of water use etc.). 'Basic measures' (set out in Article 11 of the directive) are compulsory and represent the minimum steps required to achieve 'good water status'. They include the measures required by existing EU water-related Directives.
Main elements of the WFD
• The directive establishes a clear environmental target of 'good status' for all ground and surface waters in the EU and provides a framework for the coordinated implementation of all other water legislation. It maintains existing commitments of Member States under the Nitrates Directive and Urban Waste Water Treatment Directive
• Integrated river basin management is the framework within which measures for achieving 'good status' are to be implemented.
• A River Basin Management Plan (RBMP) must be developed with transboundary basins requiring joint management between two or more Member States (and possibly with countries outside the Community).
• The precise measures to be taken within a given river basin may vary widely according to what is most appropriate - but a 'programme of measures' must be fully operational by 2012, with a progress report submitted to the Commission.
• Control of all pollutant emissions and discharges into surface waters using a 'combined approach', based not only on the overall quantity of a given pollutant, but also on its concentration in the receiving aquatic environment.
• Specific controls for certain higher risk pollutants on a priority basis, with progressive reduction, phasing out, and/or cessation of emissions.
• Water pricing is to be introduced by 2010 - acting as an incentive for the sustainable use of water resources and helping to reduce unnecessary consumption.
• Public participation is a fundamental component of the directive. Article 14 obliges Member States to ensure that draft river basin management plans are published for public consultation and comment one year before the start of the period to which the plan refers.
Integrated river basin management
The idea is that the most efficient model for a single system of water management is management by the river basin - the natural geographical and hydrological unit - rather than according to administrative or political boundaries. Initiatives taken, for instance, by the countries concerned for the Danube or Rhine river basins provide positive examples of this approach, with their cooperation and joint objective-setting across Member State borders, or as in the case of the Rhine, even beyond the EU territory.
Implementing the WFD
In order to assist WFD implementation, the EU Member States and the Commission developed the Water Framework Directive Common Implementation Strategy (WFD CIS), which was agreed in May 2001. In particular, Member States were encouraged to contribute to working groups responsible for developing analyses of pressures and impacts and best practice in river basin planning. Technical guidance from this process began to emerge from 2002 onwards. It is here that many LIFE projects have been particularly influential - promoting the key activities of the strategy, namely: the sharing of information; management of information and data; development of guidance on technical issues; and the application, testing and validation of guidance.





  

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english "Environmental problems related to Europe's rivers" з предмету "Англійська мова". Робота є оригінальною та абсолютно унікальною, тобто знайти її на інших ресурсах мережі Інтернет просто неможливо. Дата та час публікації: 25.03.2011 в 19:23. Автором даного матеріалу є Irina Milka (milka.irina@rambler.ru). З моменту опублікування роботи її переглянуто 811 та скачано 80 раз(ів). Для ознайомлення з відгуками щодо роботи натисніть [перейти до коментарів]. По п'ятибальній шкалі користувачі порталу оцінили роботу в "5.0" балів.

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