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93 Uppsatser om Climatic gradient - Sida 2 av 7
Epiphytic lichen flora in a boreal forest chronosequence
Epifytiska lavar utgör en viktig del av floran i den boreala zonen. Några miljövariabler är kända för att styra artrikedomen och artsammansättningen av epifytiska lavar på beståndsnivå, såsom träddiversitet, beståndsålder, fuktighet och trädens barkstruktur. Skogsbränder utgör den viktigaste störningen i boreala skogar men studier på brandeffekter på epifytiska lavar är mycket få. Detta arbete undersökte artrikedomen, diversiteten och artsammansättningen av epifytiska lavar på basala delar av björkar längs en gradient av 30 skogsbeklädda öar som skiljer sig i storlek och brandhistorik i den norra boreala zonen i Sverige. Målet med studien var att undersöka hur lavfloran påverkades av östorleken och miljövariablerna längs gradienten.
Termisk analys av kompakta jordvärmesystem - Sensitivitetsanalys och korrektions faktorer baserat på fältmätningar i referensanläggningar i Östergötland
Chapter 1 defines the aim of the project and gives a general orientation about ground heat extractors. In chapter 2 physical processes that could be expected to be involved in the heat transport around a ground heat exchanger are discussed. It is shown from a literature study what amount of moisture transport due to thermal gradients there could be expected in a ground heat exchanger. The conclusion is drawn that the moisture gradient (Sr) is of same magnitude as the driving temperature gradient (°C). At the expected amount of increased moisture around the pipes the moisture transport could be considered to have a little effect on the brine temperature.
Studie av koldioxidgradienter i havets ytskikt
Studie av koldioxidgradienter i havets ytskiktSofia SöderholmDenna studie bygger på ett nyligen utvecklat instrument som har mätt koldioxidkoncentrationer på tre olika djup i vattnet samt en nivå i luften. Då detta instrument var oprövat i vatten har en utvärdering av mätmetodens lämplighet för vattenmätningar utförts. Syftet med mätningarna var att undersöka ytvattnets vertikala koldioxidgradient för att med hjälp av denna kunna beskriva flödet av koldioxid mellan hav och atmosfär bättre. Detta flöde är en viktig del av den globala kolcykeln och en djupare förståelse för koldioxidflödets beteende kan i framtiden bidra till mer noggranna klimatprognoser. Hur de beräknade flödena från profilinstrumentet påverkas av temperaturgradienterna i vattnets ytskikt har även det studerats.
Hydrauliken i Ångersjöns fosforfällor : bestämning av flödesvägar och åtgärdsförslag för optimal fosforbindning vid avloppsrening med reaktiva filter
Discharge of untreated wastewater leads to unnaturally high levels of nitrogen and
phosphorus in rivers, lakes and the sea, which results in unbalanced ecosystems with
eutrophication and lack of oxygen. Part of the phosphorus in surface waters is coming from
on-site wastewater treatment from scattered households with unsatisfactory purification.
Blast furnace slag is a by-product from iron production, and has in laboratory trials showed good phosphorus binding capacity. To test blast furnace slag as a reactive filter media for phosphorus separation in a full scale experiment, a wastewater treatment plant has been built behind the picnic area at Ångersjön alongside the road E4 in central-eastern Sweden. The plant contains two parallel lines, one with blast furnaces slag and the other with Filtralite-P as phosphorus sorbent. Both filters have showed decreasing phosphorus purification effect with time in spite of a low wastewater load.
Utvärdering av en ny selektionsmetod för hingstsperma : med avseende på membranintegriteten och membranstabiliteten
Today, equine breeding is based on performance and conformation, resulting in a vast variation in fertility among different horses, with noticeable economic losses as a consequence. The horse breeding industry is therefore in need of methods that diagnose the spermatozoa concerning their quality and provide the best sperm for AI. The commonly used selection methods for sperm today are: centrifugation, where extender is added, the sample is centrifuged and then resuspended; swim-up self-migration; adherence separation; and density gradient centrifugation. However, none of these methods are in used routinely in practice before inseminating mares with fresh or cooled semen.
The aim of this study was to evaluate a new selection method, Single Layer Centrifugation (SLC), and its effect on sperm viability. The viability was analyzed with regard to membrane integrity and membrane stability of ejaculated spermatozoa.
The impact of climate change on agriculture in the Republic of Mauritius : a socio-econometric study on Mauritian farming
"Food security is a situation that exists when all people, at all times, have physical and economic access to sufficient, safe and nutritious food that meets their dietary needs and food preferences for an active and healthy life" (FAO Summit, 2003, pp. 28).Food insecurity is of concern regarding the Republic of Mauritius (ROM) since it is defined as a net food importing country. (Farming news, 2008). The impacts of climate change followed by their complexity could potentially have an increased risk effect upon the social and environmental welfare as well as the economic drivers in the ROM (www, UNESCO1, 2009). The primary victims when it comes to the impacts of climate change are the Mauritian agricultural producers since agriculture is highly dependent on climate stability, therefore affecting the yields of the producers.
Klimatförändringar och dess effekter på ogräsfloran i Sverige :
Land management for food production is a fundamental human activity and one of the greatest challenges of the 21st century will be to increase the global food to accommodate a world growing to 10 billion or more people, while undergoing climate change. The increasing temperature and the current and projected increase in concentrations of CO2 lead to concern over possible impacts on agricultural pests. This assay is summarizing the knowledge of weeds in a changing climate in Sweden. Global warming and other climatic changes will affect the growth, phenology, and geographical distribution of weeds. The climate change will also affect the weed composition indirect by causing changes in the agriculture.
Bostäder i Tyresö
Min ingång i projektet var att undersöka hur man kan bo värdigt på äldre dagar och vilka behov som uppstår. Undersökningen visade att frånsett att äldre rör sig på mer begränsade ytor så är behoven inte så olika som man kan tro. Istället för att fokusera på äldre har jag därför lagt vikt på en bostad som ska klara livets prövningar oavsett om det gäller ett brutet ben, rullstoll eller ålderdom. Bostaden ska kännas trygg, stabil och beständig. Samtidigt vill jag att den ska värna om den enskilda personens privata sfär och i hela bostadsområdet finns en gradient av olika offentlighetsgrader.
Handel med utsläppsrätter inom EU - Möjlighet eller papperstiger
This study in Environmental Science examines the amendment of the EU-Directive on. Greenhouse gas emission allowance trading. The Directive is to be considered as a tool for fulfilling the obligations that the Union and its member countries have taken on through the 1997 Kyoto agreement together with the protocols proposed at that time. The flexible mechanisms of the protocol are intended as instruments for limiting the climatic changes arising from anthropogenic sources, emission allowance trading being one of these mechanisms. The results presented here consist primarily of an analysis of interviews with various experts in the field of emission control concerning the possibilities and problems attending the process of implementation.
Implementation av webbsida för rekommendationssystem med användaruppbyggd databas
The goal of this project was to create a web-based, crowd-sourced, correlational database, that easily allowed users to submit objects and receive correlated objects as results. The webservice was created in the web development languages of HTML, CSS, PHP and Javscript, with MySQL to handle the database. Simultaneous development was kept in check with the aid of the source code management system GIT. Upon completion, the service contained several HTML-views, the ability to add and rate objects, a per-object dedicated page with information parsed from Wikipedia.org, and a view with objects ranked in accordance to the preferences specific to the current user. Roughly a month after the beginning of development, the website was publicly launched and promoted in order to collect data, and improvements were added to the website as needed.
Skattning av fordonsmassa med driftstatistik
In the automatic manual transmission system, Opticruise, the choice of gear is based on several parameters such as road incline, driving resistance and vehicle mass. Many different mass estimations are made during driving. A final vehicle mass is then used to determine the current gear. Construction vehicles are often not equipped with air suspension and can therefore not estimate the vehicle mass when standing still. If that sort of vehicle is reloaded while standing still an incorrect mass estimation will be used and as an effect of that also a wrong gear.
Naturlig haptisk kraftåterkoppling från volymdata
As the volumes are entering the world of computer graphics the pure volume visualisation becomes a more important tool in for example research and medical applications. But the advance in haptics --- force feedback from the computer --- is behind. In volume haptics no equal to the proxy method so popular in surface haptics has yet emerged. Some implementations of volume haptics even use surfaces as intermediate representations so that surface haptics can be used.The intention of this work was to create natural feeling haptic feedback from volumetric density data using pure volume haptics. The haptic algorithm would be implemented in Reachin API for the Reachin Desktop Display, together with other parts to build up a usable volume visualisation environment.To achieve the feeling of stiffness and friction dependent on tissue type, a proxy based method was developed.
Produktutveckling av mobil förstahjälpenstation
This thesis is about a part of the marquetrytechnique, scorching. Scorching is made by heating up something, put a veneer into the heated substance and make a controlled burning. This technique is old but still used today and have according to me great potential for development. In my work I wanted to give the scorching greater room then I earlier have seen. I wanted the scorching to be the dominant ingredient for a decorative element in a piece of furniture or an interior.
Dendroklimatologisk analys av lokalklimat vid Grövelsjön i Dalafjällen
Climate on earth is getting warmer, which effects earth?s energy balance and so forth the ocean and atmospheric circulation. In many sub-polar regions on the northern hemisphere changes due to warming of the climate can be observed. Some examples that already have been observed are shifts in tree line, towards higher altitudes and latitudes, increased ablation of Swedish glaciers and melting of the permafrost on the Siberian tundra. In Sweden climate change scenarios tell us that it will become warmer and that a higher amount of precipitation in form of rain will be an effect from this. To study climate changes in Sweden, transition zones are useful in order to observe changes in distribution of species and animal populations.
Skattning av den integrerade hydrauliska konduktivitetens variation kring Tunåsens infiltrationsanläggning : En utredning av påverkan från möjliga osäkerheter i befintlig information
Estimation of the variation in the integrated hydraulic conductivity around the Tunåsen infiltration facility - An investigation of the effects of uncertainties in existing informationAlmost half of Sweden?s drinking water volume is produced from groundwater. The main fraction of this is extracted from eskers, some of which allow for very large extraction rates. Despite this, the groundwater volume is not sufficient in some areas. This has led to an extensive use of artificial recharge.In Uppsala, the total volume added through artificial recharge is divided between four infiltration facilities.