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93 Uppsatser om Climatic gradient - Sida 4 av 7

Bestämning av dagvattenflöden i Knivstaåns avrinningsområde

The purpose of the thesis was to map the hydraulic load on the Knivsta river from stormwater runoff, and build a platform for further studies of pollution loads on the rivers ecosystems. New residential areas are planned to be built in Knivsta municipality and it will have an impact on stormwater flows to Knivsta river. To examine the impact this will have, simulations were made in the area as it stands today and after expansion work. The work includes calculation of flows from the populated areas but also from the catchment area around it consisting of woodlands and fields. Because of expected climatic changes which may affect rainfall, the simulations have been performed with different return periods for rainfall data.

Skillnader i kungsörnens (Aquila chrysaetos) flyttningsmönster beroende på ålder och klimatfaktorer : En studie för skyddet av kungsörn

This study examines the factors that influence the seasonal movements of Golden Eagles (Aquila chrysaetos), and can thus provide important information that helps to improve the protection of the species. There were two main purposes of this study. First, I wanted to analyze the difference between preferences of juvenile and adult Golden Eagles in their choice of southern or northern hibernation areas. Do younger eagles prefer moving longer distance to southern areas of Sweden? Second, I wanted to investigate how the climate influenced the choice of date of migration in the fall.

Att systematiskt hantera kunskap vid planering av ny infrastruktur : En fallstudie om skyfallsskador på riksväg 90 i Kramfors kommun

Natural disasters are becoming more common due to climate change and it is important to adapt the society and its infrastructure to withstand events such as extreme rainfall. Precipitation is an important climatic factor affecting the transport and annually generates the cost of millions in damages, over the past 40 years heavy rain has increased and will continue to increase in the future. The extreme rainfall that occurred in Kramfors municipality in September 2013 led to flooding and destroyed several roads, including highway 90, which recently both had been rebuilt and given a new stretch of road. Extreme rainfall had also occurred in the municipality earlier.  The aim of the thesis was to examine how the Swedish Transport Administration handles new knowledge gained after natural disasters and how this is used in the planning of new roads.

Detection of interesting areas in images by using convexity and rotational symmetries

There are several methods avaliable to find areas of interest, but most fail at detecting such areas in cluttered scenes. In this paper two methods will be presented and tested in a qualitative perspective. The first is the darg operator, which is used to detect three dimensional convex or concave objects by calculating the derivative of the argument of the gradient in one direction of four rotated versions. The four versions are thereafter added together in their original orientation. A multi scale version is recommended to avoid the problem that the standard deviation of the Gaussians, combined with the derivatives, controls the scale of the object, which is detected.

Hur påverkas bentiska funktionella födogrupper av kalavverkning? : Effekt på abundans, samt återhämning, av funktionella födogrupper efter kalavverkning kring små vattendrag.

Forestry affects most of the forest-covered land in Sweden. In the landscape, the most common stream type is headwaters, which are important sites for many processes and organisms in both the terrestrial and the aquatic ecosystems. The aim of this study was to investigate how the abundance of benthic invertebrate functional feeding groups in headwater streams develops after clear-cutting and if it also is possible to detect a change in the composition of feeding groups. The study also attempts to determine what factors have an effect on temporal changes in abundance of these groups. For the study, 11 sites in northern Sweden were sampled for benthic invertebrates using a Surber-sampler, and for each site canopy-cover and pH was obtained.

Hur ackommodativ facilitetsträningpåverkar ackommodation, vergens och binokulärseende

Syfte: Syftet var att undersöka om och i så fall hur ackommodativ facilitetsträning, med +/- 2,00DS-flippers, under en vecka, påverkar ackommodation, vergens och binokulärseende.Metod: I studien undersöktes 17 försökspersoner mellan 20-30år. Av dessa fick 3 försökspersoner avbryta medverkan på grund av olika skäl. Försökspersonerna ombeddes att sitta på 2 synundersökningar, varav en före och en efter ackommodativ facilitetsträning. Undersökningarna inleddes med ett objektivt refraktionsvärde, följt av en anamnes. Därefter utfördes en binokulär synundersökning tillsammans med binokulära mätningar, varav en mätte den ackommodativa faciliteten.

Markering och risning av basvägar inom slutavverkningstrakter : en intervjustudie hos maskinförare och planerare

In an attempt to prevent ground damage and to reduce harvesting costs, StoraEnso's districts Värmbodal and Fryken, selected a number of final felling areas where the base roads have been marked by planners in the districts. The parties involved in the experiment are mainly planners, harvester operators and forwarder operators. The purpose of this paper is to determine the findings of this trial and to find cost savings or lost revenue. This has been done with a sample of interviews from the involved parties who logged the chosen felling areas. Literature about the interview process has been used to facilitate data collection, interpretation and analysis of the material. If we look at profitability based on assumed income and expenditure, revenue per MWh would be 63 SEK.

En analys av nattliga koldioxidflöden i en boreal barrskog avseende spatial och temporal variation

Carbon dioxide in the atmosphere contributes to the greenhouse effect, which is essential tolife on our planet. Furthermore, it plays an important part of the photosynthesis andrespiration of the world?s organisms. Since the start of the industrial revolution the amount ofcarbon dioxide in the atmosphere has increased exponentially. The main source is theextensive burning of fossil fuels.

Beror KRAV-grisars ledanmärkningar på miljöfaktorer?

This project investigated how elevation and vegetation type influences variation in plant litter phenolic content and protein precipitation capacity among and within common plant species for two different vegetation types, heath and meadow, in a subarctic ecosystem in the Abisko region of northern Sweden. As nutrient availability generally decreases with increasing elevation as a result of decreasing temperature, I hypothesised that phenolic content would increase with elevation and be higher on the heath than the meadow. To test this, the total phenolic content and protein precipitation capacity was estimated in leaf litter from 13 species in both heath and meadow vegetation across an elevational gradient ranging from 500 to 1000 meters above sea level (m.a.s.l.) in the study region. The results showed that elevation and vegetation type both had a strong impact on both variables. Total phenolic concentrations decreased with elevation for the meadow, and were greater for the heath than the meadow.

Matting of Natural Image Sequences using Bayesian Statistics

The problem of separating a non-rectangular foreground image from a background image is a classical problem in image processing and analysis, known as matting or keying. A common example is a film frame where an actor is extracted from the background to later be placed on a different background. Compositing of these objects against a new background is one of the most common operations in the creation of visual effects. When the original background is of non-constant color the matting becomes an under determined problem, for which a unique solution cannot be found. This thesis describes a framework for computing mattes from images with backgrounds of non-constant color, using Bayesian statistics.

Implementation of a Data Handling System for a Scientific  Magnetometer on a CubeSat

Since their invention in 1999, CubeSats have become a widespread standard for small picosatellite missions. CubeSats allow for quick development of satellite payloads and launch in space without the high costs of a normal satellite. Emphasis during the CubeSat design process is placed on use of commercialoff- the-shelf (COTS) components and reuse of previously-designed units.This report describes the interfacing of a scientific magnetometer, the Small Magnetometer in Low-Mass Experiment (SMILE) to such a CubeSat mission, the Space Weather using Ion spectrometers and Magnetometers (SWIM). Design of a complete platform for use in multiple such missions is presented here.Modularity is one of the key aspects followed in the course of the work. A new board containing the analog pick-up and compensation circuitry for SMILE has been designed to fit inside a CubeSat frame.

El Niño Southern Oscillation och dess atmosfäriska fjärrpåverkan.

This paper is a literature study aiming to describe scientists newest theories andknowledge concerning the El Niño and Southern Oscillation. Firstly I have described the?normal? conditions with rising and sinking air in Hadley- and Walker-cells in theequatorial Pacific and from there moved on to explaining the reversed circulation patternsand higher sea surface temperatures (SST) leading to rising air and anomalousprecipitation in eastern Pacific constituting the El Niño phenomenon. My outermostinterest regarding El Niño has been the associated teleconnections, especially in nontropicalareas. I have described the El Niño effect on the Indian summer monsoon, ontropical cyclones and on storms and precipitation on higher latitudes.

Brandrelaterade insekters lokala artrikedom i förhållande till olika miljövariabler : Fokus på betydelsen av konnektivitet på brandfält i boreal skog i Västerbottens län

The last century, forest fires have decreased in frequency due to efficient fire-suppression along with the growth of the industrial forestry. Since 1990, fire has been reintroduced under controlled forms to recreate burnt habitats. Many species that are dependent on, or benefits from, forest fires have increased since fire was reintroduced. The importance of connectivity is often addressed in ecological research. This is particularly important for species dependent on short-lived habitats such as burnt forests.

OneCore

The Swedish building and property management sector are responsible for about 30 % of the total energy use. In order to take environmental consideration, different environmental assessment tools and standards are used. Miljo?byggnad, Svanen, FEBY12 and PHI are some of these. There has been increased interest to certify buildings and therefore it is of interest to evaluate the assessment of the energy field to see if relevant energy aspects are assessed.

Increased growth in Norway spruce (Picea abies (L.) Karst.) through small annual additions of nitrogen (N) fertilizer

This project investigated how elevation and vegetation type influences variation in plant litter phenolic content and protein precipitation capacity among and within common plant species for two different vegetation types, heath and meadow, in a subarctic ecosystem in the Abisko region of northern Sweden. As nutrient availability generally decreases with increasing elevation as a result of decreasing temperature, I hypothesised that phenolic content would increase with elevation and be higher on the heath than the meadow. To test this, the total phenolic content and protein precipitation capacity was estimated in leaf litter from 13 species in both heath and meadow vegetation across an elevational gradient ranging from 500 to 1000 meters above sea level (m.a.s.l.) in the study region. The results showed that elevation and vegetation type both had a strong impact on both variables. Total phenolic concentrations decreased with elevation for the meadow, and were greater for the heath than the meadow.

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