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1616 Uppsatser om Surface water - Sida 44 av 108

Pre-spawning habitat selection of subarctic brown trout (Salmo trutta L.) in the river Vindelälven, Sweden

Habitat selection of migratory brown trout at the upper reaches of River Vindelälven, wasstudied in September during the pre-spawning period. The fish migrate from down- orupriver lakes for spawning in the river and data was collected by habitat mapping andradio-telemetry. Habitat selection of fish was analysed with preference curves andstatistical modelling, using the physical variables; depth, stream velocity and streambedsubstrate. Preference curves were derived by comparing fish habitat use with their nearbyavailable environment while the statistical modelling aimed to answer three main questions.1) Do the trout have a specific preference of depth, water velocity and streambed substrate?2) Is there any difference in habitat selection between sexes? 3) Is there a shift in habitatselection over time? The preference curves indicated that trout favored water depths of 1-2m, velocity compositions characterized as glides (c.

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).

Design av motorstyrd lyfthjälp till toalettstol

The objective with this project was to design a new lifting aid connected to toilet chair.A questionnaire distributed at three homes for aged people indicated that there was an interest in a mechatronic lifting device.Since existing products have limited tilting functionality, the new design was chosen to introduce lifting by motorised tilting of the sitting platform. The mechanical construction was analyzed based on a maximum load caused by a person with weight 160 kg. Two linear actuators were used to control the tilting/lifting of the sit ?place, making standing-up easer.Finally, 28 persons tested the new lifting device and gave their impressions. Many appreciated the safe, stable lifting speed.

Stadsparken i Trelleborg - en resa i historien

This thesis was performed as assignment from Fazer Food Services. The aim was to survey which food additives that were present in the products in the quotation list of one of their suppliers to the Education and Nursing segment. The aim also was to perform a theoretical analysis of these food additives and to make recommendations which food additives are acceptable and which should be excluded from the products in the future. The recommendations are not published in this report, for more information Fazer Food Services can be contacted. Food additives which have already been approved are regarded as safe according to the safety evaluation methods available at the time of approval.

Soil carbon in small-holder plantain farms, Uganda : a comparison between agroforestry and non-agroforestry

Smallholder farmers in Uganda suffer from declining productivity. With a rapidly increasing population, marginal land is taken into production and the current land management leads to loss in soil fertility and escalation in soil erosion. There are studies indicating that the use of agroforestry increases soil organic carbon (SOC) compared to systems without trees. Soils which are high in carbon have many advantages, for example better water holding capacity, which can reduce stress on crops during drought. The aim of this study was to determine the effect agroforestry has on SOC concentration in small-holder farming systems in Uganda. The intended system to study was farms practicing agroforestry methods or not in intercropped plantain (cooking banana) fields.

Markanvädnings och markvård på småskaliga farmer i Bungomadistriktet, Western Province, Kenya

In Northen Bungoma, Western province ? Kenya, the Vi-Agroforestry Project (VI-AFP) has introduced a new project that covers 7000 households. To succeed with the project, a water resources protection project, agroforestry methods will be implemented to secure the water quality of the area. In this thesis a foundation is laid for future follow-up studies of land cover and land use of this area. To carry out this study an existing method from a cooperation between VIAFP and Dalarnas University (HDa) has been implemented.

Textila cylindrar - experiment kring solljusreglering

Working with a three-dimensional shape that adjusts light seemed exciting. Venetian blinds became a basis and source of inspiration in my project. What is a Venetian blind? I arrived at the de?nition ?a surface of angleble pieces for sun adjustment?. From that simpli?ed meaning I started making sketches of what an alternative model could look like.

Synoptisk provtagning i vattendrag med eutrofieringsproblem : En studie för att identifiera områden för prioritering av åtgärder

In Halland, agriculture is the major source of eutrophication of water. In the study, synoptic sampling were performed in the three watercourses Nyrebäcken, Skintan and Vinån all located in the county of Halland. Sampling occurred during the period February to May on three occasions with different flow rates: high, low and base flow. Samples were taken in the mainstream and tributaries with intention to show how big the impact of eutrophication it is in the water and  to assess the impact of the tributariesThe results show that all watercourses are affected by eutrophication. Nyrebäcken has the highest concentrations of nitrogen and phosphorus in the mainstream, then Skintan and last Vinån.

Död ved i vatten - funktionella strukturer och dess påverkan på öring (Salmo trutta, L.)

The background to this work was to see if there was a connection between large woody debris (LWD) and the presence of brown trout in our Swedish forest streams. Previous researches by Degerman et al. (2004) have shown that there is a strong correlation between the amount of dead wood and the presence of brown trout. The goal was then to find a way to restore, maintain and increase the trout habitats by constructing and adding manmade wooden structures that would mimic natural deadwood and its features in flowing water. The inspiration was partially taken from a water restoration program in the Klamath River of northern California, USA.

Värmeslag hos hund : Förebyggande åtgärder, djurägarråd och omvårdnad

The objective of the essay was to identify the nursing care required by a dog suffering from heat stroke and how to educate and advice the owners how to start treating their dog and prevent the condition from occurring in the first place. The essay is based on a literature study. Several databases were searched for scientific research to try find answers to the issues. Keywords concerning the subject were used and mixed in different combinations to sort out the suitable studies. The results of the study indicate that the dog should be cooled by the owner directly after detection. The most crucial issue is to reduce the body temperature as quickly as possible or the morbidity will worsen.

Etanolmetabolismen ur ett alkoholistperspektiv : Kemin vid nedbrytning av etanol i kroppen, dess betydelse för kroppens kemiska processer i övrigt samt dess betydelse för hälsa och sjukdom

The present study discusses the metabolism of ethanol in the human body from the ingestion of ethanol to the excretion of its break down products water and carbon dioxide. Ethanol is a small molecule, soluble in water as well as in organic solutions. It is quickly distributed to every section in the body, where it exerts a direct toxic effect on the cells. Ethanol cannot directly leave the body efficiently so it needs other metabolic pathways. The molecule is metabolized by oxidation, predominately in the liver.

Avsättningsmöjligheter för slaggrus från avfallsförbränning vid Åmotfors Energi

The incineration of waste is steadily increasing in Sweden and so is the production of ashes. The bottom ash has for many years been used as construction material in landfills. Now many of the nation's landfills are closed and there is a great need to find another beneficial use for the ash. Bottom ash is a gravel-like material and with its material properties it can replace natural gravel in parts of roads and surface constructions. Today this use is only approved within landfill areas where leachate is collected and checked.

Elektrolytisk reduktion av zink vid reningsprocess

When cylinders for motor saws are manufactured there are high demands on the cylinders strength and wearing qualities. Aluminum is a material with low density and is used by Husqvarna AB for their motor saw cylinders. The aluminum is strengthening with nickel that is attached to the cylinders through electrolysis. When aluminum is in contact with oxygen a film of oxide is formed. To eliminate the oxide and to prevent formation of new oxide zinc is used.

Utlakning av tungmetaller från Skörby deponi

The purpose of this thesis has been to assess whether leaching from one particular Swedishlandfill site, Skörbytippen, is contributing to elevated levels of heavy metals in a ditch runningfrom the landfill site to the lake Mälaren in the communal region of Håbo kommun. Since theditch is stretching approximately five km downstream from the landfill site, in situ observationsand maps with known points of inflow was utilized to determine appropriate test points for thecollection of samples.Soil, water and sediment samples were collected and analyzed for content of organic material, pHand conductivity. Data on plant-available elements and total amounts of heavy metals wasacquired through ICP-analysis.The results show that the Skörby landfill is currently in the methane-forming anaerobedevelopment phase, which indicates that the concentration of free and complex-bound metals inthe leachate water should be low due to chemical binding with other landfill compounds. The pHof the sediment samples was generally one unit higher than the soil samples and some of themeasured data, such as pH and conductivity, show that an environmentally disturbing dischargeof some kind of strongly alkaline chemical(s) has been made from Benders? takpanneindustri inclose proximity to the landfill.

Opera i Stockholm, Galärvarvet

En ny Opera på Galärvarvet i Stockholm. Klippformad volym som landar i vattnet och sveper ner över land. Absolut närhet till Stockholms hjärta, vattnet, samt influenser från kobbar och skär från stockholm yttre skärgård..

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