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2014
Rapporten viser overskridelser av tålegrenser for forsuring av vann og jord, samt overgjødslingseffekter på vegetasjon, med
avsetningsverdier for perioden 2012–2016. Det er kun en liten reduksjon i areal med overskridelse siden forrige periode: For
vann, ved bruk av SSWCoaa-modellen er 7% av Norges areal overskredet (8% i forrige periode). Bruk av FABoaa-modellen, som
forutsetter et mye større forsuringsbidrag fra nitrogen, gir en overskridelse på 19% av Norges areal (20% i forrige periode).
Overskredet areal for overgjødslingseffekter på vegetasjon er 20% (21% i forrige periode). Tålegrensene for forsuring av
skogsjord er ikke overskredet. Noen oppdateringer av tålegrensene har blitt gjort, primært for overgjødsling av vegetasjon. Det
er også benyttet en ny metode for beregning av avsetninger. Ingen av endringene gav store forskjeller i totalt overskredet areal,
men noen forskjeller i hvor man finner overskridelser og størrelsen på overskridelsene.
Norsk institutt for vannforskning
2018
2013
2015
VKM has assessed the positive and negative effects on biodiversity were sterile salmon to be used in Norwegian aquaculture. Triploidisation is assessed as the most effective method for sterilising fish, but it can affect the welfare and health of the fish.
Several other techniques for producing sterile salmon are being tested, but it is too early to determine whether they can be used in large-scale farming.
This is the key message in a knowledge summary VKM has prepared for the Norwegian Environment Agency.
Background
Escaped farmed salmon poses a major threat to wild salmon in Norway. hey can interbreed with wild salmon, genetically alter them, and make the populations less adaptable and more vulnerable to disease and environmental changes. A possible solution to the problem may be to use sterile salmon in farming.
To date, only triploidisation has been tested. Newly fertilised eggs are given a hydrostatic pressure shock, thereby retaining an extra set of chromosomes which render the fish sterile. This method is currently the only one tested on a large scale. Triploidisation is effective but can also pose health and welfare challenges to fish.
Methods
VKM has reviewed available scientific literature regarding methods that can be used to produce sterile salmon. VKM has assessed whether these methods work as well, or better, than triploidy and whether they are likely to have fewer negative effects on fish welfare. Assessments have also been made of whether farmed fish treated with other sterilisation methods pose a greater or lesser threat to wild salmon than traditional farmed salmon.
VKM has looked at the possibilities for further development of the triploidisation technique and has also assessed various methods currently being tested for producing sterile fish. Some of these are still at the laboratory-testing stage, while others are approaching trials with release into sea-pens. VKM has grouped the different methods based on whether they cause permanent changes in the genome (so-called "knock-out" of important genes) or whether the changes only result in temporary blocking or downregulation of gene expression (so-called "knock-down").
Results
VKM concludes that triploidisation remains the most effective method and that there are possibilities to further develop this methodology through targeted breeding and adjustments in how the fish are kept. These measures can potentially solve the challenges for fish health and welfare. Using pure triploid female lines can also reduce some of the other challenges by preventing spawning interactions in rivers and reducing disease transmission to wild salmon.
Alternative sterilisation methods, such as gene editing, vaccination, and temporary downregulation of proteins for gonad development using antisense oligomers and egg immersion, are promising but still under development.
VKM assesses that methods causing permanent changes in the genome of diploid fish have a higher inherent risk than methods that only affect gene expression.
Hope in egg-bathing
Perhaps the most promising technique for safe production of sterile salmon is to add synthetic oligonucleotides to the eggs at an early stage, thereby preventing germ cell development without causing any inheritable changes. Such oligonucleotides can be injected into the eggs or absorbed by the eggs through bathing (immersion) in a special solution.
"Especially the method involving targeted 'tools,' such as oligonucleotides that prevent germ cell development and can be added to the eggs in a water bath, seems promising," says Johanna Bodin, member of the Panel for Genetically Modified organisms and spokesperson for the report.
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2025
2015
2019
NILU and GIOS, Poland, are implementing the project "Strengthening the air quality assessment system in Poland, based on Norwegian experience" as part of the programme "Improving Environmental Monitoring and Inspection" within the framework of the European Economic Area 2009-2014.
This report describes the Norwegian emission inventory practices and emission data collection for the purpose of modeling in support of air quality assessment. The report compares and describes differences between the Polish and Norwegian rules and practices for data collection, assessment, and reporting of air pollutant emission.
2014
2001
Overview of recent activities and future plans regarding POPs at CCC. Powerpoint presentation. NILU F
2004
2010
2012
2008
2012
2011