Global ETD Search

1	Knubbsälen i Kalmarsund Bergström, Lisa January 2014 (has links) Knubbsälens beståndsutveckling i Kalmarsund styrs av flera faktorer som till exempel: överfiskning och bottendöd som reducerar mängden tillgänglig föda; fysiska störningar på reproduktionslokalerna vilket ökar kutdödligheten; miljögifter som påverkar hormonbalansen och immunförsvaret samt att populationen i Kalmarsund har en låg genetisk variation vilket gör dem extra sårbara (Härkönen, 2006). Att ha tillgång till en metod med vilken man kan konstatera små förändringar i en sälpopulation kan göra att man tidigt får en indikation om att något händer i den marina miljön. Trots en stor hotbild så visar inventeringar att populationen ökar årligen sedan inventeringens start på 70-talet. I detta examensarbete ges en bakgrund till vilka faktorer som kan tänkas påverka knubbsälspopulationen i Kalmarsund och i arbetet presenteras dessutom en inventeringsmetodik som med hög styrka kan avslöja relativt små populationsförändringar. Resultaten visar att det skulle räcka med 5-6 års inventering för att med nittiofem procents säkerhet kunna avslöja en femprocentig ändring i populationstillväxt för knubbsälarna i Kalmarsund. / The population of harbor seal in the Baltic Sea is affected by many factors such as over-fishing and benthic dead zones which reduce available food; haul-out sites disturbances which can increase pup mortality; environmental toxins which disturb their hormonal balance and immune system, and the harbor seal population in Kalmar sound has a low genetic variation that makes them vulnerable. To be able to observe early changes in the marine environment, it is important to have a survey methodology that is able to detect small changes in the seal population. Although many potential threats, the yearly population surveys shows an increase in the population since the start of the seventies. This thesis will give a background to the factors that might have an effect on the harbor seal population in Kalmar sound, and presents a population survey method with a high statistical power that is able to detect small population changes. The results show that it would take 5-6 years of surveying to detect a 5 percent increase in the population growth of the Kalmar sound harbor seals with a 95 percent statistical probability. Knubbsäl säl Kalmarsund inventering inventeringsmetodik styrkestest
2	En husurna i Fälle : En diskussion om husurnans och rösens betydelse under Bronsåldern i nordöstra Smålands kustlandskap Sjöstrand, Maria January 2008 (has links) <p>In this essay I aim to examine how the landscape of Mönsterås might have looked like during the Bronze age in order to get a better understanding of the house urn that C J Ekerot found in a cairn in Fälle. Mönsterås is an area which has a quality of permanence, from Stone Age to Iron Age with its culmination during the Bronze Age. I will discuss the use and symbolic meaning of the house urn. The house as a symbol during the Bronze Age seemed to have had an important place in the cosmology. I will also discuss the importance of cairns, especially in the archipelago areas. The cairns have had an obvious connection to the sea throughout the Bronze age and scientist have argued that one of the reason could be that the sea was associated with the dead.</p> House urns Cairns Bronze Age Mönsterås Kalmarsund Småland Archaeology Arkeologi
3	En husurna i Fälle : En diskussion om husurnans och rösens betydelse under Bronsåldern i nordöstra Smålands kustlandskap Sjöstrand, Maria January 2008 (has links) In this essay I aim to examine how the landscape of Mönsterås might have looked like during the Bronze age in order to get a better understanding of the house urn that C J Ekerot found in a cairn in Fälle. Mönsterås is an area which has a quality of permanence, from Stone Age to Iron Age with its culmination during the Bronze Age. I will discuss the use and symbolic meaning of the house urn. The house as a symbol during the Bronze Age seemed to have had an important place in the cosmology. I will also discuss the importance of cairns, especially in the archipelago areas. The cairns have had an obvious connection to the sea throughout the Bronze age and scientist have argued that one of the reason could be that the sea was associated with the dead. House urns Cairns Bronze Age Mönsterås Kalmarsund Småland Archaeology Arkeologi
4	An ecological study of the migration, food composition and relative abundance of three-spined stickleback (Gasterosteus aculeatus) in a shallow area in Kalmar Sound. Söderling, Peter January 2013 (has links) The populations of three–spined sticklebacks (Gasterosteus aculeatus) in the Baltic Sea have increased tenfold over the last decade. A large increase in abundance can alter the offshore and coastal food webs. Despite of these facts, there are large gaps in the knowledge about the stickleback ecology in the Baltic and the possible effect they might have on their environment. Earlier investigations state that stickleback mainly occupy the deeper areas offshore, and only migrate to the shallow areas during May–July to spawn. Observations by recreational fishermen indicate that this may be incorrect, and that some adult sticklebacks are present in the shallow areas even during the winter. One aim of this study was to investigate the timing of stickleback migration to a shallow coastal area in Kalmar Sound. The study also aimed to examine the relative abundance in two adjacent shallow areas in the archipelago south of Kalmar, where one of the areas is a pike spawning ground. A one month long test fishing with fyke nets was started on the first day after ice break. Results show that the sticklebacks are present in the bays immediately after the ice break, and that high abundances coincide with the pike spawning period. Stomach analyses showed that sticklebacks consumed a large proportion of crustaceans, but also fish eggs were found. These results shed new light on the management actions for many of the coastal spring spawning fish species that have shown decreasing abundances during the last decades. / Bestånden av storspigg (Gasterosteus aculeatus) i Östersjön har ökat markant, data visar på en tiofaldig ökning under det senaste decenniet. Ökningen kan medföra att bl.a. näringsväven, till havs och längs kusterna förändras. Trots vetskapen om detta finns det kunskapsluckor kring spiggens ekologi och dess möjliga påverkan på sin omgivning. Litteratur säger att spiggen till största del bara befinner sig inne längs kusterna under maj-juli. Observationer från sportfiskare tyder på att detta inte stämmer, och att vuxen storspigg befinner sig inne längs kusten och i skärgårdsvikar året om. Ett syfte med studien var att undersöka när spiggen kom in till de grunda vikarna i Kalmarsund. Studien jämförde även spiggtätheterna mellan två närliggande områden där den största skillnaden var födan. Ett månadslångt provfiske inleddes den första isfria dagen i två skyddade vikar söder om Kalmar, där en av lokalerna var en dokumenterad leklokal för gäddor. Resultaten visade att spiggen fanns i vikarna direkt efter islossningen, och vid fisket sammanföll de största spiggfångsterna med gäddleken. Maganalyser visade att en stor andel av födan bestod av olika kräftdjur, men även romkorn hittades. Resultaten tyder på andra förutsättningar för många av de hårt ansatta vårlekande fiskarterna än vad som tidigare är dokumenterat. Three-spined stickleback Gasterosteus aculeatus migration abundance population decline increase food prey predate pike perch roach spring spawn recruitment shallow Kalmar Baltic Storspigg spigg vandring förekomst population populationsökning populationsminskning föda byte predera predator gädda abborre mört vår vårlekande föryngring lek grunt Kalmar Kalmarsund Östersjön

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