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124 Uppsatser om Fish - Sida 3 av 9

Naturvärdesbedömning av Utanåfladen; En inventering av vårlekande fisk, bottenfauna och vegetation

There are several thousands shallow bays along the Swedish east coast. Most of them are disturbed by different human activities, and undisturbed bays can be considered as quite unique. In the sheltered shallow bays water warms up more rapidly than adjacent water favoring the growth of vegetation, which in turns is beneficial to spring spawning Fish species like perch and pike. It is nowadays more common that coastal habitats are inventoried to facilitate future preservation and planning. The aim of this study was to investigate the shallow bay Utanåfladen (59° 53`31.38 N 19°00`44.90 E) in the north Stockholm archipelago and evaluate its habitat value.

Predation på evertebrater under tidig vår i sjön Tåkern

Benthic invertebrates play important roles as feeding resources for many organisms in different food webs. Shifts in predation of these organisms can generate cascading effects and potentially lead to the disappearance of one or more species from a site. Cascading effects can bring impacts to organisms who aren?t even directly involved, why studies in this field are important for understanding sudden changes in ecosystems. I examined the predation from Fish and waterfowl on benthic invertebrates in the shallow and eutrophic Lake Tåkern in the plains of Östergötland County, southern Sweden.

Beteende inför lek hos odlad respektive vild lax (Salmo salar L.) i Klarälven

In many regulated rivers, authorities have stocked hatchery salmon to compensate for loss of wild populations. However, hatchery Fish have not always behaved as wild Fish do, and stocking them has not always fully compensated for the loss of wild Fish. The purpose of this study was to compare swimming behaviour in the river before spawning, the choice of spawning areas and body size between wild and hatchery-reared salmon in the river Klarälven. Salmon behaviour in the river before spawning was analyzed using radio telemetry. The salmon were caught at Forshaga power plant, radio-tagged and returned to Klarälven at Ekshärad, 107 km from the river?s mouth.

Vattendragsrestaurering i teorin och fiskinventering i praktiken : en litteratur respektive metodstudie

Running water-pathways have played an important roll in Sweden and frequently been manipulated. One profound change was made during the period of logging when streams were cleared from obstacles as big boulders, sharp bends and side-streams. Dams and different constructions gave control of the stream water and the streams became channel-like with a homogen structure. This interference gave problems for many Fish populations and resulted in a shortage of feeding habitat, over-wintering habitat, spawning habitat, unnatural flow regimes, sedimentation, unnatural temperature fluctuations. Many of these historical changes of the watersheds are now subjects for restoration, ie., bring back the streams to what we believed it was before the change. However, what once existed in terms of complexity is now gone and difficult toreplace.

Småskalig vattenkraft : Dagsläge och framtidsplaner

This study focuses on small scale hydropower in Sweden. This means plants with a capacity of up to 10 MW. The study has a special focus on plants with a capacity up to 2 MW. The study has three aims. It strives to describe the small-scale hydroelectric industry in Sweden.

Optimering av FISH- teknik för detektion av Laktobaciller

SammanfattningSyftet med den här studien var att utveckla och optimera Fish (Fluorescense In Situ Hybridisation) tekniken som en snabb och ganska billig metod för detektion av laktobaciller. Det vill säga att kunna på objektsglas använda Fish tekniken för att identifiera laktobaciller på artnivå med fluorescensmärkta prober mot 16S och 23S RNA. Fish är en allmän och användbar metod för att detektera och lokalisera mikroorganismer eller en specifik grupp av mikroorganismer i provet (1). Metoden detekterar DNA- eller RNA- sekvenser med hjälp av fluorescensmärkta prober som hybridiseras specifikt med komplementära målsekvenser i intakta celler (2). Detta innebär att man behåller cellmorfologin och tillför en lättdetekterad fluorescerande färg.

Drank som proteinkälla till regnbågslax (Onchorhynchus mykiss) :

The objective of the present study was to evaluate distillers? dried grains with solubles (DDGS) as a protein source to rainbow trout (Oncorhynchus mykiss), by studying digestibility and growth measurements. One control diet, totally lacking DDGS, and three test diets were made containing 10 % (low), 31% (medium) and 51 % (high) DDGS respectively on dry matter (DM) basis. The control diet and the test diets were made to be as nutritionally equal as possible. Wheat bran was used to balance the fiber content of the diets.

Fisk- och fågelpredations påverkan på den bentiska makroevertebratfaunans sammansättning under tidig vår i Tåkern

Predation is one of many factors that form the structure of the macroinvertebrate community in lakes, wetlands and watercourses. Earlier studies lack an examination concerning how Fish- and waterfowl predation affect macroinvertebrates during shorter periods in the spring. I performed an exclosure study in the shallow eutrophic Lake Tåkern which is located in the western part of Östergötland County, Sweden. The experiment was performed during a three week period (1-21 April 2012) when the water temperature was low and the density of migrating diving ducks was high. The experimental cages used included three out of four different treatments; general predation (open cages), bird exclusion (net with mesh size 90*45mm) and no predation (net with mesh size 1*1mm).

Influence of the habitat on the potential for cannibalism and population dynamics in stream-dwelling European grayling (Thymallus thymallus L.)

Cannibalism can have major influence on Fish population dynamics. A prerequisite for cannibalism is that the cannibal and the potential victim meet, and besides density effects, the encounter rate between cannibals and their victims is therefore also largely dependent on habitat use and habitat heterogeneity. In this study I quantified and compared the potential for cannibalism in stream-dwelling European grayling populations in three rivers in Jämtland by means of habitat classifications. I also analyzed population dynamic consequences of varying the potential for cannibalism in terms of intensity, using a physiological structured population model. Findings based on habitat characteristics were that the potential for cannibalism is in general not favourable in these types of streams.

Utveckling i Ammerån : att skapa ett hållbart fiske med hög kvalitet

Ammerån which is a small forest river in eastern Jämtland is a well-known river that has been a popular Fishing river for a long time. The actual Ammerån begins downstream the lake Solbergsvattnet at Hammerdal and flows into the Indalsälven 10 km upstream Hammarstrand. The river environment switches between forests with wilderness feeling and open agricultural land. The entire Ammerån is today a nature reserve and protected from hydropower development. Fishing in Ammerån has mainly been focused on trout and grayling, and is so even today.

Det obetydliga : om fiskhuvudformiga hängen, sociala praktiker och förändring, 600-1200 e. Kr.

Fish-head pendants are one of the characteristic Gotlandic Late Iron Age artefacts. This object has been rather neglected and mainly considered as an insignificant embellishment, normally worn as a neck-collar and seen as an artefact include in the typical Gotlandic set of female jewellery.The fact that the Fish-head pendant has a very long life span, which stretches from grave-finds in the Early Vendel Age to hoards in Viking Age as well as secondary usage as brooches in the Early Middle Ages, makes the artefact an excellent starting point for discussions on social practices and change through material culture. It's shown in this study that, contrary to previous beliefs, the normal usages for Fish-head pendants is as solitary pendants and not as neck-collars. Neck-collars is shown to have an intricate relation to inhumations for young individuals, whereas solitary pendants are found in cremation deposits for adult individuals, something that relates to a fixed social practice mainly in the period 700-900 AD and that develops from the cremation funeral practice. This particular social practice relates to aspects of attraction and protection and continues in to the 10th century outside of funeral structures, which is shown by the composition of hoard-finds from the 10th century, but is totally absent when the pendants is given a secondary usage as brooches in the end of the 11th and beginning of the 12th century.

Bestämning av utfallet av translokationen t(11;18)(q21;q21) hos patienter med MALT-lymfom genom FISH analys

Lymphoma is a group of malignant tumour diseases developing in the secondary lymphatic system. These diseases can develop in all organs as lymphocytes are ubiquitously in the body. In connection to mucus membranes we find mucosa-associated lymphoid tissue, MALT, in which lymphoma can spontaneously but slowly develop, mostly at chronic inflammation or at autoimmune diseases. Today these diseases are incureable with the exception of some cases caused by Helicobacter pylori-infection. Antibiotic treatment of these cases can induce remissions.MALT-lymphomas have characteristic histological and molecular properties.

Förekomst av kontaminanter i importerad fisk : en litteraturstudie

A literature review of contaminants; cadmium, methylmercury, dioxins, and PCB, for eleven different Fish species (Greenland halibut, gilt headed bream, sea bass, wolfFish, hoki, ocean perch, angler, Nile perch, pangasius, red snapper and tilapia) that were selected in concurrence with the National Food Administration. The result can be used by the National Food Administration to gain further knowledge about the different Fish species to be able to continue to give advice to varied risk category and the public. The gilt headed bream and sea bass were the only Fishes whose values for mercury exceeded the limit of 0,5 mg/kg (EU Reg. 1881/2006). In the angler, Nile perch and pangasius the mean value of mercury didn?t exceed the limit, however in some individuals the mercury content did exceed what is allowed.

En utvärdering av temperaturproblem samt närsaltsbelastning i odlingsdammarna och Flugströmmen i Harasjömåla

This bachelor?s project deals with both the problems of high water temperatures in Fishponds at a Fish-breeding station and of the nutrient load to nearby lakes and streams in Harasjömåla, Blekinge, Sweden. Theory, methods and results of the analyses are presented in the report..

Migration losses of Atlantic salmon (Salmo salar L.) smolts at a hydropower station area in River Åbyälven, Northern Sweden : passage fates at a reservoir, a power house and a bypass structure

A large number of rivers in northern Sweden have hydropower developments that cause negative effects on both up- and downstream migrations of anadromous species like Atlantic salmon. So far, most attention has focused on the hindrances of adult Fish during their upstream spawning migration. However, since turbines in power stations cause losses on downstream passing Fish, the focus on negative effects on smolts has increased. The aim of this study was to compare three different causes of losses of salmon smolts passing downstream through a power station area in the flow-controlled River Åbyälven in northern Sweden.A total of 61 wild salmon smolts were caught and radio-tagged in the River Åbyälven during their downstream migration in June 2009. The salmon smolts were released at three locations, 1.1 km upstream from the power station, in the turbine intake and in the upper part of a Fishway, acting both for up- and downstream Fish passage.

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