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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

The Lunar Nodal Cycle Influence on the Barents Sea

Yndestad, Harald January 2004 (has links)
<p>The Barents Sea contains one of the most productive marine areas in the world. For centuries, Northeast Arctic cod and Norwegian spring spawning herring have been of vital importance for the Norwegian fish export industry and hence economic growth in Norway. It has been common knowledge that the biomass of different Barents Sea species experiences both shortand long-term fluctuations. These fluctuations have been explained by changes in herring cycles and cod cycles, or by the introduction of new fishing equipment, and more. Norwegian marine research began in earnest at the beginning of the 19th century. The main task for researchers was to discover how nature influenced cod stocks and the effects these fluctuations had on the lives of people who depended on fishing for a living. Nearly 100 years later, scientists still disagree over the causes for the biomass fluctuations in the Barents Sea. At the same time, marine research has produced long time series, which can now be analyzed using new methods. This thesis represents an investigation of a number of long time series of Arctic climate indicators and biomasses in the Barents Sea. The purpose of this analysis has been to identify a potential stationary cycle in the biomasses. A stationary cycle in the biomass allows for expanded possibilities for better long-term biomass forecasting.</p><p>The methods are based on general systems theory, analysis of systems dynamics and a wavelet analysis of time series. The wavelet analysis has identified the cycle time and the cycle phase of the dominant cycles in the time series. The phase-relation between the identified cycles contains information abort the dynamic chain of events between climate indicators and the biomasses in the Barents Sea.</p><p>The investigation has identified harmonic and sub-harmonic cycles of the 18.6-year lunar nodal cycle in all analyzed time series. The identified lunar nodal spectrum is explained by a gravity force from the 18.6-year lunar nodal cycle as the First Cause. The energy from the 18.6-year gravity force from the moon introduces a chain of oscillating events. The oscillating gravity introduces a lunar nodal spectrum in the lunar nodal tide and the polar position. A wavelet analysis of time series indicates that movement of the polar position introduces a new lunar nodal spectrum of circulating water in the Arctic Ocean. This circulation water interacts with the 18.6-year lunar nodal tide in the Atlantic Ocean and introduces an oscillation in the extent of Arctic ice, and an oscillation in the inflow of the Atlantic Ocean to the Barents Sea. The lunar nodal spectrum of Atlantic inflow introduces a lunar nodal spectrum in the Barents Sea ecology system. Analysis of the biomass in the Barents Sea shows that long-term growth, reduction and collapse are associated with the phase-relation between the biomass eigen dynamics and the lunar nodal spectrum of Atlantic inflow.</p> / Papers I - VI reprinted with kind permission of Elsevier, www.sciencedirect.com
12

The Lunar Nodal Cycle Influence on the Barents Sea

Yndestad, Harald January 2004 (has links)
The Barents Sea contains one of the most productive marine areas in the world. For centuries, Northeast Arctic cod and Norwegian spring spawning herring have been of vital importance for the Norwegian fish export industry and hence economic growth in Norway. It has been common knowledge that the biomass of different Barents Sea species experiences both shortand long-term fluctuations. These fluctuations have been explained by changes in herring cycles and cod cycles, or by the introduction of new fishing equipment, and more. Norwegian marine research began in earnest at the beginning of the 19th century. The main task for researchers was to discover how nature influenced cod stocks and the effects these fluctuations had on the lives of people who depended on fishing for a living. Nearly 100 years later, scientists still disagree over the causes for the biomass fluctuations in the Barents Sea. At the same time, marine research has produced long time series, which can now be analyzed using new methods. This thesis represents an investigation of a number of long time series of Arctic climate indicators and biomasses in the Barents Sea. The purpose of this analysis has been to identify a potential stationary cycle in the biomasses. A stationary cycle in the biomass allows for expanded possibilities for better long-term biomass forecasting. The methods are based on general systems theory, analysis of systems dynamics and a wavelet analysis of time series. The wavelet analysis has identified the cycle time and the cycle phase of the dominant cycles in the time series. The phase-relation between the identified cycles contains information abort the dynamic chain of events between climate indicators and the biomasses in the Barents Sea. The investigation has identified harmonic and sub-harmonic cycles of the 18.6-year lunar nodal cycle in all analyzed time series. The identified lunar nodal spectrum is explained by a gravity force from the 18.6-year lunar nodal cycle as the First Cause. The energy from the 18.6-year gravity force from the moon introduces a chain of oscillating events. The oscillating gravity introduces a lunar nodal spectrum in the lunar nodal tide and the polar position. A wavelet analysis of time series indicates that movement of the polar position introduces a new lunar nodal spectrum of circulating water in the Arctic Ocean. This circulation water interacts with the 18.6-year lunar nodal tide in the Atlantic Ocean and introduces an oscillation in the extent of Arctic ice, and an oscillation in the inflow of the Atlantic Ocean to the Barents Sea. The lunar nodal spectrum of Atlantic inflow introduces a lunar nodal spectrum in the Barents Sea ecology system. Analysis of the biomass in the Barents Sea shows that long-term growth, reduction and collapse are associated with the phase-relation between the biomass eigen dynamics and the lunar nodal spectrum of Atlantic inflow. / Papers I - VI reprinted with kind permission of Elsevier, www.sciencedirect.com
13

Hållbart fiske i Östersjön : Möjligheter och problem

Brander, Jonas January 2012 (has links)
No description available.
14

Sveriges framtid, möjligheter och begränsningar inom en cirkulär bioekonomi baserad på skogsråvara / Sweden's future, opportunities and limitations within a circular bioeconomy based on forest raw materials

Teandersson, Johanna January 2023 (has links)
Studien syftar till att klargöra nuläget i den svenska skogsbaserade bioekonomin. För- och nackdelar med olika utvecklingsmöjligheter har studerats, begränsningar finns för utvecklingen och framtidsmöjligheterna för en cirkulär bioekonomi i Sverige. Den dominerande råvarubasen för den cirkulära bioekonomin i Sverige är skogen. I dagsläget är det framför allt massa-, pappers- och sågverksindustrin som är väl utvecklad och kan räknas till en framgångsrik cirkulär bioekonomi i Sverige. En cirkulär bioekonomi bidrar till en grön omställning för att fasa ut användningen av fossila råvaror, vilket anses vara den största fördelen. Politiska beslut både i Sverige och inom EU kan genom vissa lagförslag begränsa tillgången på råvaror, det är också det största hotet. Möjligheterna är främst långsiktiga spelregler, där tydliga ramverk, affärsmodeller och bioekonomistrategier tas fram.
15

Att undvika en arktisk tragedi : Kollektiv förvaltning av fisket i Arktiska oceanens internationella vatten

Högberg, Tomas January 2017 (has links)
In a time of climate change the Arctic region is undergoing rapid changes, and the decreasing sea ice cover is expected to draw increased commercial interests as The Arctic Ocean gets more accessible for resource exploitation. The central part of the ocean is common area, where, in theory, overfishing may result in a tragedy of the commons and related fish stocks collapse. This study aims to provide insights into how fishing in the central Arctic Ocean relates to successful collective management, and was conducted using Elinor Ostroms design principles and The Logic of Collective Action as a framework for an ideal type inspired analysis. The results show that conditions for collective fisheries management in the central Arctic Ocean are relatively good, and it’s concluded that collective fisheries management is already embraced and enacted upon by several actors. However, to attain the ideal state of collective management further improvements are required, although there are also multiple options as to how such requirements could be met and there was no indication of why collective management would be unsuccessful. / I samband med ett förändrat klimat så genomgår även den arktiska regionen snabba förändringar, där den minskande havsisen i Arktiska oceanen ger ökad tillgång till naturresurser och förväntas dra allt större kommersiella intressen. Den centrala delen av oceanen är en allmänning, vilken enligt teorin kan överfiskas och resultera i en allmänningens tragedi och relaterade kollapser av fiskbestånd. Denna studie ämnar ge en insikt i hur fisket i centrala Arktiska oceanen förhåller sig till lyckad kollektiv förvaltning, och utfördes genom att låta Elinor Ostroms designprinciper och det kollektiva handlandets logik utgöra ett ramverk för en idealtypsinspirerad analys. Resultaten visar att förutsättningarna för kollektiv förvaltning är relativt goda och att fisket i viss utsträckning redan förvaltas kollektivt. För att uppnå en idealtypisk kollektiv fiskeförvaltning framgår det dock att ytterligare insatser behövs men att det även finns flera alternativ för att möta dessa behov, och det fanns heller ingen antydan av att kollektiv förvaltning skulle misslyckas.
16

Towards a Sustainable Fisheries Management : How to address uncertainty in order to achieve a sustainable development of regional fisheries management

Folkesson, Malin January 2010 (has links)
Fisheries management is not only about managing the resource fish, but also includes managing the social system. Aquatic ecosystems and the social system are both complex and change continuously. It is important to address what types of uncertainty the combination of both systems, complex socio-ecological systems leads to, their consequences and how these should be dealt with. Successful or unsuccessful management outcomes are difficult to address whether or not they are due to management efforts or natural changes. In addition, uncertainties often lead to a short-term management, since lack of knowledge makes it difficult to act in a long-term perspective. This thesis conceptualizes how to address different types of uncertainty prevalent in fisheries management, with focus on natural process uncertainty, measurement and estimation uncertainty, decision and implementation uncertainty, and institutional and regime uncertainty.  This was done by analyzing how three theoretical approaches, namely co-management, adaptive management and adaptive co-management address these uncertainties. In order to highlight how different types of uncertainty have been dealt with in practice, a case study on the fishery management in Lake Vättern has been made. A comparison between the literature study and this thesis’ case study shows that hypothesis-testing, cooperation, communication and transparency are corresponding factors on how to deal with uncertainties in fisheries management and that institutional and regime uncertainty is inadequately addressed in Sweden.
17

Tough Guys Don't Cry : en diskursiv och semiotisk medieanalys av gråt och maskulinitet

Steen, Therese January 2010 (has links)
My intention with this essay has been to examine how men’s tears are portrayed in three chosen films and what their crying does to their masculinity. In my analysis I have used the concept of hegemonic masculinity. I have worked from the assumption that in our culture men’s crying is problematic in some sense. By using both a semiotic and a discursive method of analysis I have investigated why and how these men are crying, and I have mapped out the similarities and differences between the three films. My conclusion is that the effect on the crying man’s masculinity is largely dependant on the degree of his previous fulfillment of hegemonic masculinity.
18

Ekens historia och förekomst i Elleholm socken, Blekinge : en kvantitativ jämförelse över tid utifrån ekinventeringsprotokoll från åren 1819, 1830–31 samt nyinventering 2019

Malm, Patrik, Balaj, Liridon January 2020 (has links)
I århundraden har eken varit betydelsefull i Sverige. Kronans syfte var att kontrollera och lagstifta eken för tillgången på skeppsvirke. Det hårda lagstiftandet och kontrollerna bidrog till att avverkning av eken förbjöds på krono- och skattejord. På 1800-talet upplöstes dispositionsrätten vilket ledde till att ekbestånden minskade. Idag är äldre ekar med höga naturvärden viktiga miljöer då de hyser olika mikrohabitater som gynnar den biologiska mångfalden. Syftet med studien har varit att med hjälp av historiskt material jämföra antalet ekar med dagens invertering. I området Elleholm, i Blekinge, har en sådan inventering inte genomförts på över 200 år. Studien undersöker historiska källmaterial som ekinventeringsprotokoll över Elleholm socken för åren 1819, 1830–1831. Insamlade data har sedan jämförts med nutida inventering. Ute i fält har även ekens hålighet, vitalitet och omkrets noterats för att se över ekens kondition. Det framtagna resultatet visar att antalet ekar har minskat drastiskt sedan protokollen skrevs. Data som samlades in efter inventeringen kring ekens kondition gällande överlevnad är positiva. Nedgången på antalet ekar kan bero på att dispositionsrätten upphörde att gälla under 1830-talet. Vidare kan även den ökade befolkningstillväxten lett till att jordägarna avverkade eken illegalt och legalt. Resultatet visar att ekarna i området Elleholm är i bra kondition, vilket kan bero på gallring och öppenhet i landskapet. På grund av nedgången av ekbestånden skyddas ekarna genom de lagar som reglerar skyddandet av ädellövskog samt ”jätteträd”.
19

Olika markberedningsmetoders effekt på granplantors (Picea abies) överlevnad och höjdtillväxt vid Siljansfors försökspark / Effects of different soil scarification methods on survival and height growth in Norway spruce seedlings (Picea abies) planted in Siljansfors Experimental Forest

Johansson, Anders January 2018 (has links)
Markberedning är vanligt förekommande när återbeskogning skall ske efter en avverkning. Vilken metod som väljs styrs av olika faktorer som t ex markfuktighet, humuslagrets tjocklek och mineraljordlagrets djup. I detta arbete studeras ett försök vid SLU: s försökspark i Siljansfors, ca 20 km SV om Mora. Studien omfattar två olika försöksytor, Sf 284 och Sf 287, planterade med gran (Picea abies) år 2004 respektive 2007. Ståndorten är en moränmark, markfuktighetsklassen är frisk och vegetationstypen är blåbär- och lingontyp och är belägen cirka 210 m.ö.h.  Syftet med denna studie är att utvärdera och jämföra tre olika markberedningsmetoder med avseende på överlevnad och höjdtillväxt hos granplantor (Picea abies) under de första åren efter plantering. Vid plantering utan markberedning och utan kemiskt behandlade plantor är risken för en hög avgång på grund av skador orsakade av snytbagge (Hylobius abietis L.) stor de första åren. De markberedningsmetoder som jämfördes var högläggning, fläckmarkberedning och inversmetoden. Dessa tre metoder jämfördes inbördes samt mot att inte markbereda alls. I det totala samlade plantmaterialet var hälften kemiskt behandlat mot snytbagge. Fördelningen kemiskt behandlat och obehandlat plantmaterial var jämt fördelat i alla försök och upprepningar. I studien ingick också en utvärdering av den så kallade ”kanteffekten”, dvs. effekten av att plantorna sattes närmare än, respektive längre än 10 cm från kanten av den anlagda markberedningsytan. I juli 2009 mättes planthöjd och överlevnad på försöksytorna. Resultatet presenteras som medelvärden i form av stapeldiagram. Överlevnadsgraden höjdes med hjälp av markberedning, permetrinbehandling och val av planteringspunkt i förhållande till humuskant.  Det var framför allt högläggning och inversmarkberedning som gynnade plantornas höjdtillväxt. / Soil preparation is common when reforestation occurs after harvesting. Which method is chosen is governed by various factors such as soil moisture, humus layer thickness and depth of mineral soil. An experiment was made at SLU's experimental park in Siljansfors, about 20 km SW about Mora. The study comprises two different experimental areas, Sf 284 and Sf 287, where Picea abies was planted in 2004 and 2007 respectively. The soil is a moraine, the soil moisture class is fresh and the vegetation type is blueberry and lingonberry type. The site is located approximately 210 m above sea level. The purpose of this study was to evaluate and compare three different soil preparation methods regarding to survival and height growth of Picea abies during the first years after planting. In the case of planting without soil preparation and without chemically treated plants, the risk of a high mortality due to the damage caused by pine weevil (Hylobius abietis L.) is high during the first years. The soil preparation methods that were compared were mounding, patch scarification and the inverse method. These three methods were compared to each other as well as to no soil preparation at all. In the total aggregate plant material, half were chemically treated against pine weevil. The distribution of chemically treated and untreated plant material was evenly distributed throughout all trials and repeats. The study also included an evaluation of the so-called "edge effect", i.e. the effect of placing the plants closer than, respectively, longer than 10 cm from the edge of the scarified patch. In July 2009, plant height and survival were measured in the experimental areas. The result is presented as averages in the form of bar charts. The survival rate was increased by soil preparation, permetrin treatment and selection of planting point relative to humus edge. It was above all mounding and inverse soil preparation that favored the height of the plants.
20

"The Sibyl was safe in her jar, no one could touch her, she wanted to die" : Possessing Culture and Passion in A.S. Byatt's Possession

Jackson, Maria January 2017 (has links)
The purpose of the essay is to discuss the power narration has over our gender roles. John Fiske and Pierre Bourdieu´s theoretical texts have been used to discuss the connection between power and culture in A.S. Byatt’s novel Possession: A Romance. Possession demonstrates how male academics take part in shaping knowledge about the past and the present from their perspective. Byatt uses allusions to myth and folktales to emphasise both the romance theme of the novel and how the past has formed us and continues to affect us in our relationships and social roles. The novel reveals how women are trapped by cultural myths about women’s roles in society. The female characters’ fates demonstrate the complexity of heterosexual relationships for independent women in a society where women are supposed to be taken care of by men. The roles imposed on women in romance stories in particular can be seen as a reductionist patriarchal view of women. Byatt emphasizes how women who at varying levels do not collaborate with men are punished for their chosen lifestyles and how some, like homosexual women, have been removed or have chosen to remove themselves from society in different ways. Byatt attempts to demythologize social myths concerning women and men by rewriting traditional myths and fairy tales. Still, Possession does not ultimately challenge the importance of the heterosexual relationship or the male and female characters’ gender roles.

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