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567 Uppsatser om Pollution load - Sida 36 av 38

Predicting spawning bed erosion and longevity : a case study in tributaries to river Vindelälven, northern Sweden

Timber floating operations in Scandinavia during the 19th and 20th centuries has contributed to severe negative impacts on riverine ecosystems. Increase in water velocity and lack of stream bed heterogeneity as a result of stream channelization lead to increased bed load transport. Since availability and recruitment of new suitable spawning substrate in Scandinavian watercourses is sparse, spawning habitats for salmonids has become a scarce commodity. Lately, increasingly more attention has been given to the recreation and improvement of brown trout (Salmo trutta) spawning habitats in restoration projects. While much of the research on spawning habitat has been focused on evaluation of the influence that the constructed spawning grounds have on fish populations, few studies have been conducted to evaluate the persistence of these constructions over time. I evaluate erosion of constructed spawning beds as an effect of sediment transport attributable to water discharge.

Produktivitet vid stubblyftning :

Stump wood was used between 1850 and 1950 for production of tar and as firewood. In the 1950s the use decreased because of the introduction of the cheap fossil oil. In the 1970s stump wood became an interesting issue again as a raw material for the pulp industry. Stump lifting has today become a possible source for bioenergy. The objectives with this study were to investigate the productivity of stump lifting and stump extraction, and to analyse the economy.

Anaerob psykrofil behandling av hushållsavloppsvatten i UASB : Utvärdering av kapaciteten hos en två-stegs UASB-reaktor för behandling av hushållsavloppsvatten

Hammarby Sjöstad is a new district in southern Stockholm. A main objective with the Sjöstad project was to halve the environmental impact compared to other construction work. The environmental goals involve a halved water consumption rate, a local treatment of storm water and trials aiming to extract nutrients from the waste water. Sjöstadsverket is an experimental treatment plant used for testing new treatment processes for domestic waste water from Hammarby Sjöstad. The results are to be compared with the conventional process used at Henrikdals treatment plant today.

Inverkan av försvagningar på bärförmåga för stålbalkar med långa spännvidder : En jämförelse mellan Eurokod och BKR

The purpose of this thesis is to investigate the degree of influence of holes in the web of steel beams with long spanson weakening of their bearing capacity. Making holes in the web of the beam generally reduces the bearing capacity of the beam. However, it might be necessary seen from both an architectural perspective as well as from a building services perspective by creating an opportunity for building installations.The objective of this thesis is to examine how much an I-beam can be weakened without sacrificing safety and functionality. The investigation has been done by using Finite Element Method through commercial software.The regulation for structural design of building structures in Sweden used to be specified in the document known as BKR. But this was replaced by the European norm Eurocode back in May 2011.

Kemisk karaktärisering samt nedbrytning av process- och avloppsvatten vid SCA Ortvikens pappersbruk

During pulp and papermaking process a huge amount of water is used. The wastewater contains a large amount of pollutants and has to be treated before it reaches the recipient. In March 2004 a new bleaching plant was started up at SCA Graphic Sundsvall AB, Ortviken?s paper mill using peroxide. The production of bleached thermo mechanical pulp and thus the load to the wastewater plant increased.

Tekniska möjligheter för artificiell spridning av renlav :

Forestry and reindeer husbandry are entitled to use the same land for their operations. For this reason, conflicts occasionally arise between them. Soil scarification is a forestry operation which has a negative effect on the occurrence of reindeer lichen. Reindeer lichens are of crucial importance to reindeers and reindeer husbandry, especially in the winter when reindeers primarily feed on different lichen species (Cladina spp. and Cetraria spp.).

Utvärdering av kalkstens egenskaper med laboratorie- och fältmetoder.

A pavement construction designed to cope with the different type of traffic loads; it is exposed to and at the same time it can resist the effect of the climate. A road structure consists of sub- and superstructure which is divided by a boundary known as terrace. During the construction of unbound layers (base course and sub-base course) in the superstructure, it is always ensured that the material meet the requirements for bearing capacity and the degree of compaction. These parameters are controlled by various laboratory tests and control methods. To obtain increased knowledge of the material and improve the quality of the compaction in the field, it is necessary to perform laboratory tests in order to determine material properties.A base course material 0/ 32 mm limestone from Gotland (Hejdeby) was investigated in this study.

Miljöcertifiering av ett byggnadsminne

Samtidigt som debatten kring jordens klimatförändring är i full gång har intresset för att miljöcertifiera byggnader vuxit oerhört. För fastighetsägare är det en möjlighet att bevisa för sina hyresgäster och köpare att byggnaden är hållbar. Är en byggnad miljöcertifierad har en oberoende part intygat att den uppfyller en nivå av hållbarhet som bestäms utifrån standardiserade kriterier. Fastighetsägaren kan alltså använda certifikatet i marknadsföringssyfte.Den här studien undersökte om en byggnad som är byggnadsminnesförklarad kan miljöcertifieras med Miljöbyggnad. Målet var att hitta kostnadseffektiva lösningar för att uppfylla de miljöcertifieringskriterier som eventuellt inte uppfylls idag.

Pilotinstallation av fast och fjärravläst nätstationsmätning : Identifiering av för- och nackdelar med nätstationsmätning, Mälarenergi Elnät AB

Today?s electrical grid companies understand that better knowledge of and information about their grid can help realize a smart grid network. One way to gain better knowledge and information about the low voltage network is to install measuring equipment on the substation transformer´s secondary low voltage side that measures the low voltage network losses for that specific substation. By doing so, grid companies can, due to the calculation of the low voltage network losses, identify and address issues such as illegal power dissipation, unmeasured power outtakes, and unsatisfied technical documentation for the substations low voltage network.During 2012, Mälarenergi Elnät AB had a total electrical network loss (both medium and low voltage network losses included) of three to four percent of their total distributed electrical volume. Converting this energy volume into a monetary figure this accounts for a loss of around 30 million Swedish crowns.

Bergerosion i utskovskanaler

Today?s climate changes will probably give rise to precipitation in Sweden, which will cause more floods in Swedish rivers. Many of the Swedish rivers are regulated and have lots of hydro-electro power plants. Higher floods in the rivers will give greater water loads on the dams, which mean that a higher discharge through the sluice gates and in the spillway channels is needed. High discharge of water in a spillway channel can create scour of the material in the channel.

Urban Agriculture i den hållbara staden : en fältstudie i Managua

The way we design our cities today will affect the living conditions for future generations. Planning as a discipline can become crucial to attain a sustainable urban development with an increased quality of life among the urban population and an improved environment. Urban Agriculture in the Sustainable City -a case study in Managua is a Diploma Work that deal with poverty issues, aspects of sustainability and development work. We have had a theoretical starting-point, but our focus has been on the case study i.e. the practical part, that we carried out in Managua, the capital of Nicaragua. Today about half of the worlds 6,3 billion people live in cities. The demographic growth of the countryside has declined, while the population in the cities is considerably increasing.

Hästägares kunskapsnivå och attityder angående hästutfodring

Horse owner?s knowledge about horse feeding and nutrition is directly linked to the horse?s health and welfare. According to several studies, both Swedish and foreign, horse owners generally have inadequate knowledge about horse feeding. The housing systems and feeding routines of today differs in many ways from what horses have adapted to through evolution. Wild horses live in harem herds and roam on large open fields, spending about 60 % of the day grazing, mainly grass and herbs.

Djursjukskötarens roll i rehabiliteringen av inneliggande patienter på hästsjukhus

Veterinary hospital care and advanced veterinary services are rapidly growing industries. As of January 1, 2010, veterinary nursing became a licensed vocation, the title of veterinary nurse became protected, and the act regulating competence among the professions of the veterinary field was extended. These changes, along with increased demands and expectations from owners, have given rise to greater demands on the staff's qualifications and have increased the need for well-educated staff with expertise in several different areas. The aim of this study was to find out what the licensed veterinary nurse can do in terms of rehabilitation for the hospitalized equine patient suffering from orthopedic injury. This has been carried out through qualitative interviews with veterinary surgeons experienced in treating such patients, and also by reviewing the relevant literature.

Restriktioner av växthusgasemissioner : hur påverkas lantbruksföretagens ekonomi och produktionsinriktning?

The agricultural sector accounts for about 13 percent of the total load of greenhouse gas emissions from Sweden (Swedish Environmental Protection Agency, 2007). The Swedish objective to reduce the greenhouse gas emissions with 40 percentage units to the year of 2020, based upon the year of 1990, might imply stricter regulations for Swedish farmers. A regulation or other forms of economic incentives is probably necessary to reduce the emissions originating from the agricultural sector. This study aims to investigate the economic and managerial impact on two agricultural firms with differing production system given that a constraint on green house gas emissions is introduced. Gases included in this study are carbon dioxide, methane and nitrous oxide.

Dagvattenutredning för Hamrebäcken : Utredning av föroreningsbelastning och framtagande av åtgärdsförslag för att förbättra vattenkvaliteten

Hamrebäcken rinner genom östra delen av Västerås och har Mälaren som recipient. Under bäckens flödesväg tillkommer dagvatten och föroreningar i form av näringsämnen och tungmetaller från dess avrinningsområde. Bäcken utgör ett av de mest prioriterade vattendragen i Västerås gällande utsläpp av dagvatten. Detta examensarbete har utförts med syftet att utreda föroreningssituationen för Hamrebäcken och hur dess recipient Mälaren påverkas. Examensarbetet syftade även till att undersöka reningseffekten för en befintlig dagvattendamm samt att utifrån ett kostnads- och reningsperspektiv beskriva ett antal åtgärdsförslag för att uppnå en förbättring av bäckens ekologiska och kemiska status.

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