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4669 Uppsatser om Water level - Sida 5 av 312
Hot och risker med dricksvattenförsörjning : Förutsättningari tid och rum för bevarande av Sundsvalls och Timrås dricksvattenförsörjning
This study describes what impact activity within Wifstas, Matfors,Grönstas and Nolbys water protection areas have on the quality of the drinkingwater. It considers the use of the area, environmentally dangerous activitiesin the past and present, the geology?s part, what harm hydroelectric power damsmay cause if they break and how climate change might affect the area in thefuture. It also takes into consideration activities outside the waterprotection areas which might have a suspected impact on the water quality. Theresults of the study are that pollution from infrastructure such as roads, orwastewater from treatment plants may cause occasional contamination of thedrinking water, foremost due to flooding.
Modellstudie av föroreningsretention i Bäckaslövs våtmark : Tillämpning av modellverktygen MIKE SHE WET och MIKE 21
During the nineties, ecological handling of urban storm water became very popular in Sweden. Together with Chalmers University of Technology and two Swedish communities, DHI Water and Environment has been doing research of storm water ponds and constructed wetlands. This thesis work is a part of that research project. The work has been applied at the Bäckaslöv storm water treatment plant in Växjö, Sweden. The plant consists of one storm water pond and a downstream constructed wetland.
Vilken preferens har tjockskalig målarmussla (Unio crassus) för bottensubstrat och vattenhastighet i Storån, Östergötland?
The thick shelled river mussel (Unio crassus) has a fragmented distribution in southern Sweden. It is a threatened and protected species. In both the Swedish red list and the IUCN Red List of Threatened Species Unio crassus is classified as Endangered (EN). Causes for this classification are for instance differentiated bottom substrate and deterioration in water quality. In this study, habitat preferences of Unio crassus were investigated to assist in future restoration work.
Troubleshooting med avseende på avsättningar på gummiduk, Bobergs tryckeri AB
Bobergs printing house in Falun has during some time had problems regarding deposits on blankets intheirs Müller Martini UV-printing presses. Deposits appear in both image areas and non-image areas.These areas have been analyzed and the deposits on non-image areas contain chalk, clay and talc. Thequestion remains how these material bond to the blanket surface. The chalk and clay comes from thepaper. The talc comes from the ink.
Ut ur Östersjön genom vassen : beskrivning av övergödningsproblematiken samt optimering av en reningsmetod genom skörd av vattenväxter
This study is based on AgroSeas business idea from environmental problems to valuable resource, with the objective to optimize a method to purify the already eutrophicated Baltic Sea by harvesting water plants, mainly reed. The nutrients will then be recirculated to arable land through residues from biogas production. The amount of nutrients that can be removed by harvesting the biomass
depends on the amounts of biomass and the nutrient content of it, which in turn is strongly dependent on the nutrient concentration of the surrounding water. Vegetation suggested in the study for an effective nutrient uptake is helophytes: reed, cattails, reed canary grass, reed sweet
grass in shallower water and lemnoideaes: duckweed and nymphaeids in the deeper parts.
Competitive species has high purification ability but requires regular maintenance to avoid channeling and overgrowth. Regarding time and method of harvest, effectiveness may be improved by: harvesting plants above the Water level and after flowering, a border is kept, harvesting twice a season, a bigger machine and a regular maintenance.
This literature has illuminated a major environmental problem and it has been suggested
optimizations for a method for cleaning the Baltic Sea through harvesting water plants, but to get a
definite answer for the optimal method for each site tests should be carried out, this because many
factors determine to what is suitable for each, specific environment.
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Grundvattenpåverkan kring järnvägstunnlar i berg
Rock groundwater has always caused major problems when tunnelling. Water leaking into tunnels can cause large problems, not only on the construction itself but also on the environment. A continuous water leakage can lead to a declining water supply, and geotechnical problems can occur as subsidence in the ground. Therefore it is of great importance to predict the consequences that can appear in the surroundings due to a declining groundwater surface.The aim of the study was to investigate different methods for predicting leakage and changes in groundWater level due to tunnelling excavations in rock. This thesis was performed by comparing mathematical methods, actual groundwater changes and results from preliminary investigations.Investigations were made for three railway tunnels planned by Botniabanan AB.
Fuktkvotens inverkan på oljeupptag och pigmentinträngning i tall (Pinus sylvestris L.) och gran (Picea abies L. Karst) vid impregnering med Linotechmetoden :
Wood has always been an important material for people, and it is used for many applications. As for example, fuel for cooking and heating houses, construction materials and for constructing means of transport. Since wood also is a material that with time biologically degrades due to activity by micro organisms and wood fungi it is important to find ways to protect and further lengthen the life span of the material when in service. One method is to decrease the amount of water in the material by impregnation with an hydrophobic oil. The Linotech method which uses only pure linseed oil is one such possible method.
The aim of this study was to investigate the possibility to at the same time impregnate and stain/colour wood samples of pine and spruce by using the Linotech method.
Är Lerbodaälven verkligen en problemälv? : undersökning av fosforhalter
Lerbodaälven is a river in the municipality of Kil which, due to high phosphorus content is not meeting the requirements for good ecological status according to the Water Framework Directive. The purpose of this report is to investigate the causes for the high content of phosphorus that has been measured in Lerbodaälven between 1995-2010. Four questions will be answered in this report.
1. Does the sewage treatment work affect the phosphorus level in Lerbodaälven?
The result from the time series analysis shows that the sewage treatment works have a small impact on the phosphorus level in Lerbodaälven.
Skaftslamkrypa (Elatine hexandra) i Bolmen, utbredning, tillväxt, reproduktion och styrande faktorer
The plants in the genus Elatine are characteristic for oligo and mesotrophic lakes. This study focuses on Elatine hexandra one of the four species in Sweden. It is stated as vulnerable by the National Environment Agency and a conservation plan with guidelines to preserve the plant in Sweden is under preparation. There have been a few previous studies investigating this plant in other countries but this is the first one for Sweden. The aim of this study was to investigate the distribution, growth and reproduction of E.
Klimatförändringar på ön Fongafale, Tuvalu : En analys av miljöpåverkan och attityder
This thesis aimed to investigate how a rising sea level would affect the livable area of the island Fongafale, Tuvalu. Through the IPCC stabilization scenarios it was examined which areas of the island that would be affected by flooding. The local population?s perceptions of the effects of climate change were studied to see how the consequences of a world-wide problem such as global warming affect people's lives. The paper clarified the Tuvaluans place in the discussion of climate refugees, explained IPCC's work and described the results of previous studies concerning people in Fongafales perceptions and concerns about climate-related changes.
EU:s medborgarinitiativ : En framkomlig väg för att minska det demokratisk underskottet?
The European Union is struggling to maintain democracy and tries to increase the participation among the citizens in Europe. The European Citizens? Initiative, ECI, is a platform established by the European Commission to allow citizens to propose new legislation. ?Water and sanitation are a human right! Water is a public good, not a commodity!? is the first ECI that has met the requirements.
Små vatten- och avloppssystem : Möjligheter till inskränkning av verksamhtesområden
This study is focused on small scale water and wastewater handling in Sweden. The study is divided into two major parts; the first describes common methods for water- and wastewater handling and the second part is a case study on three small and expensive systems in Gällivare municipality, in the north of Sweden. In the case study, abilitys for the local government to hand over unwanted systems to the water users is investigated and found to be a plausible solution to cut costs for two out of the three studied systems. In the third case, water and wastewater systems is not recommended to be handed over but other ways of cutting costs are suggested..
Förstudie till våtmark i Rimbo : Design för optimal hydrologi och kväverening
The euthropthication of the Baltic Sea is a threat that is beginning to be taken seriously by the governments concerned. In Sweden, regulations concerning the allowed nitrogen (N) concentration in the effluent water from wastewater treatment plants are being tightened up. The Rimbo wastewater treatment plant has been imposed to reduce the annual mean concentration of total N in the effluent water to levels below 15 mg l-1. A more and more common way to reduce the nitrogen level in wastewater is to let the water pass through a wetland. This study investigates the possibility to build this kind of wetland at the outlet of the Rimbo wastewater treatment plant.A prestudy of the topography, soil characteristics and groundwater flow indicates that the land area in question is well suited for the construction of a wetland.
Översvämningskartering av Vombs ängar
Vomb meadows is an area well knows for its rich bird life. During the 19:thcentury until mid 20:th century, the meadows were flooded annually in order toincrease the hay yield. The river Klingavälsån situated along the west side of themeadows, used to be a shallow river, meandering across the landscape. In the1940?s the river was straightened and made deeper.
Inventering av processvattenbalans : fastställande av fjärrvärmedistributionens läckage inom Vattenfall Värme Uppsala AB
Heat is distributed to the district heating customers through pipes with water as a heat carrier. The district heating system is complex. To decide what is leakages from the district heating net versus what is the water consumption of the plant, is difficult.
Therefore, the purpose of this master thesis is to establish a model where the district heating net?s leakages but also the water consumption of the plant can be followed
daily. The project is performed at Vattenfall´s district heating power plant in Uppsala.
Information is gathered through discussions, drawings of the plant and guided tours of the plant.