772 research outputs found
Life cycle assessment of sea lice treatments in Norwegian net pens with emphasis on the environmental tradeoffs of salmon aquaculture production systems
No full textThe development of food production systems and the adoption of diets with lower environmental burdens are critical to mitigate the threats from climate change and the erosion of biodiversity and ecosystems. Many consider seafood to be a viable alternative source of animal protein to the most polluting types of ruminant production, such as cattle and sheep. Farmed salmon is a popular finfish providing an alternative to meat, appreciated for its taste, the quality of its proteins, and its sources of marine omega 3. Despite significantly lower life cycle impacts than most land-based animal production, the salmon aquaculture industry faces substantial environmental challenges. In Norway, large production volumes concentrated in open marine cages led to the chronic contaminations of coastal areas by viruses and parasites. This reduces production efficiency, fish welfare and threatens the stocks of wild salmon. Permanent sea lice infestations in net pens force farmers to use new delousing methods, exacerbating the situation. The Norwegian aquaculture industry is unable to increase its production output sustainably and finds itself at a crossroads. Farmers are investing in alternative land-based and sea-based aquaculture systems without a comprehensive understanding of the environmental tradeoffs involved.
This work intends to improve our understanding of the environmental strengths and weaknesses of salmon aquaculture systems. I used Life Cycle Assessment (LCA) in most of my research to account for environmental impacts generated through life cycles and value chains. First, I reviewed the salmon LCA literature and applied a simple parametric statistical protocol to compare the LCA results of different salmon systems across studies. Then, I conducted LCA of the biological, mechanical, and chemical lice treatments used by the Norwegian aquaculture industry. The rationale for this work was the recent transformation of the treatment mix and the exclusion of treatments' impacts from the LCA of net pen salmons. Finally, I used the LCA of warmwater fish RAS farming in Sweden from Bergman and colleagues and an innovative winter fallowing to control sea-lice infestations in net pens suggested by Stene and colleagues to discuss the tradeoffs and future of aquaculture systems in Norway.
Despite small data samples and multiple confounding factors, the cross-study statistical comparison was successful for some portions of the data. I demonstrate that (1) sea-based systems require significantly less energy than land-based systems, (2) land-based systems have a significantly lower feed conversion ratio than sea-based systems, and (3) closed systems likely have a significantly lower eutrophying potential than open systems. Norwegian farmers' current lice treatment mix adds significant life cycle impacts to net pen salmons, especially for the carbon, marine toxicity, and energy footprints. The main impact drivers are the increased salmon mortality, the fuel use from ships, the production of hydrogen peroxide, and the construction of mechanical treatment units. However, preliminary observations suggest that adding the treatment impacts to the life cycle impacts of net pen salmons will have a negligible effect on system comparisons. Regarding the LCA methodology itself, I argue in favor of more data reusability and interoperability using the lice treatments LCA to showcase the possibility of sharing openly human and machine-readable inventories while respecting confidentiality agreements. I also highlight the limitations of LCA for the comparison of aquaculture systems, particularly with regards to impacts on biodiversity, ecosystems, and fish welfare.
Finally, based on the current state of knowledge, I argue against the large-scale development of land-based, offshore, and closed sea-based systems envisioned by some stakeholders in Norway. I recommend testing nature’s strategy suggested by Stene and colleagues to mitigate sea lice challenges and improve the environmental profile of open sea-based systems. A low technology solution like this could allow the industry to increase its production output by keeping more fish in the cages alive
Epidemiology and Pathogenesis of Type 1 Diabetes
No full textType 1 diabetes is an autoimmune disease that affects 0.1 to nearly 1% of the population, dependent on the country, with its highest incidence around 10–15 years of age. The incidence has increased over time, approximately doubling over the past 2–3 decades. The incidence varies across the world, with the highest among populations of (Northern) European origin and the lowest in Japan. Most diabetic patients do not have affected first-degree relatives, but genetic predispostion encoded in the HLA class II DR- and DQ loci is proabably necessary, albeit not sufficient, for developing disease. Exposure to environmental factors in early life appears to also impact the risk of disease development, but available evidence does not allow for strong conclusions to be drawn. The past decade has brought new data from human pancreatic donors. Hoewever, the timing between etiological triggers and the pathogenesis is poorly defined, and the disease mechanisms need to be elucidated. It is still not possible to prevent or cure type 1 diabetes. The latter can currently only be achieved using invasive beta-cell repacement therapies through transplantation
Friendship, love, and brotherhood in medieval Europe, c. 1000-1200
No full textIn this book, Lars Hermanson discusses how religious beliefs and norms steered attitudes to friendship and love, and how these ways of thinking affected social identity and political behaviour. With examples taken from eleventh- and twelfth-century northern Europe, the author investigates why friendship was praised both by brotherhoods of aristocratic warriors and by brethren within monastery walls. Social and political functions rested on personal connections rather than a strong central state in the High Middle Ages. This meant that friendship was an important pragmatic instrument for establishing social order and achieving success in the game of politics
Historisk resistensutvikling for organofosfat og pyretroid hos lakselus (2002-2022)
No full textHavbruksnæringen anses som den nye oljen, men hemmes av biologiske faktorer som lakselus. Parasitten presser laksenæringens profittmarginer, muligheten til å opprettholde god fiskevelferd og ivareta nærliggende økosystemer. Det benyttes ulike avlusningsmetoder for å holde lusepåslag nede, hvorav kjemiske har vært foretrukket. Stor bruk i Romsdalsfjorden og Storfjorden frem til 2016 ga resistente lusepopulasjoner, nedsatt effekt og derav utfasing av organofosfat og pyretroider. I denne oppgaven har vi analysert lus fra Dryna og Gudmundset og funnet resistens-gen for begge kjemikaliene. Resultatene viser at 42% av testet lus var resistent mot pyretroider og at 10% sannsynligvis var resistent mot organofosfat. Analysene baserer seg på et begrenset antall prøver og er ikke representativt for lusepopulasjonene, men kan gi en pekepinn på dagens situasjon. Det diskuteres videre om resistensnivåene kan skyldes krysskontaminering mellom nærliggende anlegg, et latent gen i populasjonen, og/eller feil bruk av kjemikalier. Resistensnivået av pyretroider er svært høyt og en gjeninnføring frarådes.
Andelen sensitive lakselus mot pyretroider er nå rundt 1/3 på Dryna og 1/2 på Gudmundset. En avlusning med 50% overlevelse blant lus er ikke effektiv. For å kunne ha en effektiv behandling uten overdrevne konsentrasjoner bør resistensnivået senkes ytterligere. Da til rundt samme målte nivåer som organofosfat, eller ideelt sett 0%. Ved en gjeninnføring av samtlige kjemikalier i et fravær av resistens, kan behandlingene kontrolleres, rulleres og resistensutvikling minimeres. Utviklingen bør følges over tid med et oppskalert volum på prøvetakningen. Mer sikkerhet kan eventuelt fastsette en beslutning rundt gjeninnføring av pyretroider og eller en eventuell utfasing av organofosfat
Utopia i kryzys. Lars T. Lih i rozważania wokół komunizmu wojennego
No full textThe article concerns the policy of ‘war communism’ in Soviet Russia during the civil war. In historiography, there are two dominant views regarding this phenomenon – while some researchers argue that it was a crisis policy (pragmatic and determined by external circumstances), others are inclined to claim that it was a utopian policy (a frantic attempt to immediately implement the communist ideal). Based on the revisionist works by Lars T. Lih, the author argues with the interpretation of the Bolshevik utopian policy, focusing on the analysis of three basic elements of this interpretation, namely: the contingent policy in the countryside, Leon Trotsky’s book entitled Terrorism and Communism and the work entitled The ABC of Communism by Nikolai Bukharin and Yevgeni Preobrazhensky. Thus, the article is an attempt to create a different picture of the Bolshevik policy in the first years after the revolution from the one that is popular in the Polish historical discourse
Does remediation save lives? On the cost of cleaning up arsenic-contaminated sites in Sweden
No full textSwedish environmental policy is based on 16 environmental quality objectives (Gov. Bill 2000/01:130 and Gov.Bill 2004/05:150).1 One of the most challenging objectives,‘A non toxic environment’, has two interim targets that concern remediation of contaminated sites. In sum, they state that the highest priority should be given to sites posing the highest risks to human health and the environment.2 By eliminating pollutants in soil, groundwater and sediment, the interim targets aim to reduce risks to human health and the environment. In Sweden, 83,000 sites are potentially contaminated due to previous industrial activities. According to the Swedish Environmental Protection Agency (EPA), the administrator of the governmental funds for remediation, approximately 1500 of these sites contain contaminant concentrations that could seriously harm human health and the environment (Swedish EPA, 2008a). To reach the interim targets, all these sites need to be remediated by 2050. Remediation of contaminated sites has so far cost more than SEK 3,000 million.3 The approximated cost to mitigate the potential risks at the most harmful sites is estimated at SEK 60,000 million.4 The Swedish government’s funding for remediation presently comes in the form of a directed grant (sakanslag). The directed grant, administrated by the Swedish EPA, subsidises remediation of contaminated sites that were contaminated prior to modern environmental legislation (in 1969) or for which no liable party can be found. The directed grant amounts to approximately 455 millions annually, which corresponds to about 10 percent of the annual national funds for environmental protection (Gov. Bill 2007/08:1). To make it possible to prioritise among contaminated sites, the Swedish EPA has developed a method for risk assessment called the ‘MIFO’ (i.e. the Method for Inventory of Contaminated Sites). The risk assessment does not take into account the actual exposure at a contaminated site. Risk is instead assessed based on divergence from guideline values for acceptable concentrations given a standardised (i.e. worst case) exposure situation on an individual level. This means that a site can be remediated without any individuals actually being exposed. The expected risk reduction is consequently not quantified. This eliminates the possibility of valuing the risk reduction, which should be weighed against the remediation cost. The purpose of this paper is to analyse how health effects, in the form of cancer risks, from sites contaminated by arsenic are valued implicitly in remediation. By using an environmental medicine approach that takes exposure into account, and without underestimating the potential health consequences of arsenic exposure, our purpose is to place arsenic risk management in the overall picture of live-saving interventions. In the case of cancer prevention, it is necessary to recognise that focus on an environmental carcinogen like arsenic may draw public attention – and funding – away from mental health risks like ambient air pollution and indoor radon. Although environmental pollution accounts for less than ten percent of all cancer cases (Harvard Centre for Cancer Prevention, 1996; Saracci and Vineis, 2007), environmental factors are important to recognize since they may be preventable. We emphasise, however, the inefficiency in becoming overly concerned about small risks while, at the same time, losing sight of the large risks. If society’s spending on lifesaving measures with small effects (i.e. a small number of lives saved) crowds out spending on lifesaving measures with large effects, then remediation can, in fact, even be said to waste lives. By using data on 23 arsenic-contaminated sites in Sweden, we estimate the sitespecific cancer risks and calculate the cost per life saved by using the sites’ remediation costs. Our results show that the cost per life saved through remediation is much higher than that associated with other primary prevention measures, indicating that the ambition level of Swedish remediation may be too high.
Environmental crisis, sectoral versus integral: The agency of change: Dialogue
No full textToday we experience and acknowledge the nexus of ecology, culture and politics as a moving objective, defined by local realities placed within global developments. Large-scale change is no longer a distant probability but an approaching condition, which forces us to accept instability and envision sustainability transitions as the ground of future inhabitation. When looking closer into atmospheric, water (riverine, maritime, deltaic), and land systems and their inherent uncertainties we realize the agency that local sensitivities, culture and planning regimes have in defining the success or failure of sustainable development. This dialogue will question what the real ground of preMarsent and future urbanization is, imagining adaptive and transformative change as material and ecologically sensitive practices to site, context and culture.This dialogue is the transcription of the round table talk on the International Forum on Urbanism held in Delft on 26 November 2021. Lars Marcus, Chris Zevenbergen and Carola Hein presented their work in the light of the environmental crisis, sectoral versus integral: the agency of change. With moderator Fransje Hooimeijer they elaborated and related their work in a discussion around the main questions of history, the longue durée, disciplinarity and agency of change.Urban DesignHistory, Form & Aesthetic
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