objectives for the swedish environment seminar 5 zero eutrophication and a balanced marine...
Post on 17-Dec-2015
220 Views
Preview:
TRANSCRIPT
Objectives for the Swedish Environment
Seminar 5
Zero Eutrophication and A balanced marine environment
Outline
• Introduction to the process of eutrophication
• Zero eutrophication and necessary changes
• The interim targets to be met with zero eutrophication
• A balanced marine environment and necessary changes
• The interim targets to be met with the marine environment
• Shared responsibility
Eutrophication
Eutrophication is an accelerated growth of algae on higher forms of plant life caused by the enrichment of water by nutrients, especially compounds of nitrogen and/or phosphorus and inducing an undesirable disturbance to the balance of organisms present in the water and to the quality of the water concerned
Heavy eutrophication entails a distinct reduction in the number of plant and animal species in the water. A few species benefit, but at the expense of all the others
3
Eutrophication
Regions with eutrophic waters
From Monitor 14, Swedish Environmental Protection Agency
Most minor lakes in the green areas marked on the map have total phosphorus concentrations exceeding 25 µg/l.
4
The Process of Eutrophication
High nutrient
Cause
Top layer
Supporting factor
High phytoplankton biomass
Direct effect
Oxygen depletion, flora/fauna changes
Indirect effectsBottom layer
Supporting factor
5
Causes of eutrophication
The enrichment of water by nutrients can be of natural origin but it is
often dramatically increased by human activities.
6
• Main sources of anthropic nutrient input
• Runoff
• Erosion and leaching from fertilized agricultural areas
• Sewage from cities and industrial wastewater
• Atmospheric deposition of nitrogen (from animal breeding and combustion gases) can also be important.
Nutrient leakage from agriculture
Nutrient emissions from agriculture are the main reason why eutrophication has remained a serious problem in many Swedish inland and coastal waters
Phosphorus in artificial fertilizer and manure (tonnes/year)
7
Nutrient leakage from agriculture
Nitrogen compounds, unlike phosphorus, are highly mobile in the soil and crops are seldom able to absorb all of the fertilizer nitrogen
Nitrogen in commercial fertilizer and manure (tonnes/year)
8
Nitrogen in the ground water
• Concentrations of nitrogen in nitrate form have gradually risen in many wells in the agricultural areas of Central and Southern Sweden, presenting a health hazard to people who depend on such wells for their drinking water
• Infants are sensitive to nitrate, which can be converted into carcinogenic substances in the body
• More than 100,000 people in Sweden are depending on drinking
water which contains nitrate concentrations in excess of the Swedish
health limit (10 mg/l expressed as nitrate nitrogen)
9
Marine eutrophication
Emissions of nitrogen to the sea through Swedish watercourses underwent a noticeable increase during the 1970s, due above all, probably, to increased nitrogen deposition from the atmosphere and the increasing use of nitrogen fertilizer in agriculture. In spite of several different measures, no long-term reduction of this nitrogen load on the sea has so far been observed
Nutrient supply to the Baltic Sea proper and Öresund
10
• The eutrophication of seawater has entailed a significant increase in algal bloom and other vegetation growth in the coastal and sea areas concerned
• Concentrations of nutrients in these waters have recently started to decline again, but the sharp drop detected at the Gotland Deep in the winter of 2000/01 is most likely a temporary phenomenon
Marine eutrophication
Nutrients in winter in the Baltic proper (Gotland Deep station) 11
Marine eutrophication
• At the depth of 70 meters in the Baltic there is a salinity discontinuity between the surface water and the appreciably saltier bottom water, which impedes the vertical water exchange preventing highly oxygenated surface water from penetrating downwards. Consequently there is a permanent oxygen deficiency
• Roughly one-third of the Baltic is practically dead
• The deepest basins of the Baltic contain hydrogen instead of oxygen
12
Oxygen trends in the Bothnian Sea and the
Baltic proper Oxygen deficiency near the sea bed
Monitoring of eutrophication
The main reasons for monitoring a water body for eutrophication are,
13
This is mostly relevant for water companies, which have to deal with eutrophic waters
• to prevent the occurrence of eutrophication
• early warning purposes
• public health authorities need to know when eutrophication is likely to start in order to allow them to implement preventive actions
• to know the level of development of the process
• to have a precise picture of the quality of the water.
Zero eutrophication
Nutrient levels in soil and water must not be such that they adversely affect human health, the conditions for biological diversity or the possibility of varied use of land and water.
This objective is intended to be achieved within one generation
Vigorous action needs to be taken without delay if the objective is to be
attained
The environmental state described in this objective will be difficult to bring about by 2020
14
Necessary changes
• The release of nitrogen and phosphorous to soil and water must be reduced
• Atmospheric deposition must be decreased to levels below the critical loads (deposition of south-western Götaland needs to decrease to between a half and a third of its levels in 1995)
• Research is required to be able to estimate the critical loads for
phosphorous and nitrogen in different sea areas
• Levels of plant nutrient substances mainly phosphorous need to decease in about 100 extremely nutrient-rich lakes and watercourses in Southern Skåne, the lake Mälar Region, Östergötland and the area of Lake Vänern
15
Interim targets
By 2009 programs of measures as provided for in the EC Water Framework Directive will be established, specifying how good ecological status is to be achieved in lakes and streams and in coastal waters.
This target will be met, as EC legislation requires Sweden to prepare programs of measures to achieve good ecological status in its lakes, streams and coastal waters
16
By 2010 Swedish waterborne anthropogenic emissions of phosphorus compounds into lakes, streams and coastal waters will have decreased continuously from 1995 levels
Interim targets
1995 2000
1,000 tonnes
2
4 Phosphorus emissions to water fell by 15% between 1995 and 2000. Provided that additional action is taken, they should continue to decline.
It is difficult to assess whether this interim target will be met, however, owing to incomplete emission statistics for certain sources, and also because it is unclear what is meant by ‘decreased continuously ’.The Swedish EPA has been asked to define the target more precisely by 2004
17
By 2010 Swedish waterborne anthropogenic emissions of nitrogen into sea areas south of the Åland Sea will have been reduced by at least 30% compared with 1995 levels, to 38,500 tonnes
Interim targets
1,000 tonnes
1995 2000
10
30
50
70
Target 2010: 38.5
Target 2010: 47
The period 1995–2000 saw a marked reduction of point-source emissions. As yet, though, there has been no clear decrease in diffuse emissions from agriculture
If emissions and leaching and thus inputs to the sea continue to decrease according to plan, it should be possible to meet this interim target
18
By 2010 emissions of ammonia in Sweden will have been reduced by at least 15% compared with 1995 levels, to 51,700 tonnes
Interim targets
Ammonia emissions have fallen by almost 13% since 1995
1,000 tonnes
10
30
50
70
Target 2010
95 96 97 98 99 00 01
The prospects of achieving the interim target by 2010 seem good
19
By 2010 emissions of nitrogen oxides to air in Sweden will have been reduced to 148,000 tonnes
Interim targets
1,000 tonnes
90 92 94 96 98 00
Swedish emissions of nitrogen oxides have been reduced by 25% since 1990. With the decisions now taken, emissions are projected to fall to around 160,000 tonnes by 2010. Provided that additional measures are introduced
50
150
250
350
Target 2010
The target should be met. One source of uncertainty is the development of road traffic, with freight transport accounting for a particularly large share of emissions
20
A balanced marine environment
The North Sea and the Baltic must have a long-term sustainable productive capacity and biological diversity must be preserved. Coasts and archipelagos must have a high degree of biological diversity and a wealth of recreational, natural and cultural assets. Industry, recreation and other utilization of the seas, coasts and archipelagos must be compatible with the promotion of sustainable development. Particularly valuable areas must be protected against encroachment and other disturbances.
This objective is intended to be achieved within one generation
Attainment of this environmental quality objective is dependent on the objectives Zero Eutrophication and A Non-Toxic Environment being achieved.
21
Necessary changes
• The development of shallow sea areas and other coastline waters that are important for biological production must be prevented
• The shoreline must be protected. Exploitation of areas that are especia-lly valuable for nature conservation
• Fishing must be adjusted to suit the size of fish stocks to ensure the preservation of long-term production capacity and biological diversity
• For naturally occurring species in coastal areas and the sea to be preserved sufficiently, nitrogen and phosphorus emissions as well as the load from toxic substances must be reduced and the discharge of oil from ships must be prevented
22
• By 2010 long-term protection will be provided for at least 50% of marine environments of high conservation value and at least 70% of coastal and archipelago areas with significant natural and cultural assets.
Interim targets
There are currently about 140 areas of national interest which incorporate coastal and archipelago environments, but the areas selected need to be reviewed.
23
• By 2005 another five marine areas will be protected as reserves, and the competent authorities will have decided which other areas in the marine environment are in need of long-term protection
• By 2005 a strategy will have been adopted for the preservation and use of the cultural heritage and agricultural landscapes of coastal and archipelago areas.
Interim targets
24
• By 2005 action programs will have been prepared and introduced for threatened marine species and fish stocks that are in need of targeted measures.
• By 2010 total annual bycatches of marine mammals will not exceed 1% of each population. Bycatches of sea birds and undesired fish species will have been reduced to levels that have no adverse effect on the populations concerned.
Interim targets
• By 2008 catches of fish, including bycatches of juveniles, will not exceed recruitment, enabling fish stocks to survive and, where necessary, recover
25
• By 2010 noise and other disturbance from boat traffic will be negligible in particularly sensitive and designated archipelago and coastal areas.
• By 2010 discharges of oil and chemicals from ships will be minimized and reduced to a negligible level by stricter legislation and increased monitoring
• By 2009 programs of measures as provided for in the EC Water Framework Directive will be established, specifying how good surface water status can be achieved.
• Farmers, the Swedish Board of Agriculture and agricultural organizations
Shared responsibility
26
• Energy and transport sectors
• Households, tourist organizations, trade and industry and municipalities
• Regional authorities
• The national board of fisheries, fishing organizations and fishermen
• Shipping lines, the National Maritime Administration and the Swedish coast guard
top related