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4908 Uppsatser om Water protection area - Sida 22 av 328
Sammanvägda avrinningskoefficienter i rationella metoden : en jämförelse mellan idag och 1970-talet
Storm water is rain and melted snow that runs off, primarily from impervious surfaces.Future storm water management is facing the challenges of increased precipitation, asclimate changes, and increased areas of impervious surfaces due to the expansion anddensification of the cities. Impervious surfaces reduce the potential for water to infiltratein the ground leading to increased surface runoff and higher peak discharge.The runoff coefficient is closely related to the percentage of impervious surfaces andrepresents the maximum percentage of a catchment that can contribute to runoff. In thisstudy, the objective was to evaluate the weighted runoff coefficient for three differenturban types; apartment buildings, townhouses and residential areas and a comparisonbetween today and the 1970`s was made.The runoff coefficient was determined by manual mapping of the different surface typesin each area based on data in the form of orthophotos and aerial photographs. The surfacetypes that were mapped were asphalt, permeable areas, tiles, sand/gravel and roof.Tiles and sand/gravel were the most difficult surface types to map. In order to see towhat extent these categories influenced the weighted runoff coefficient a sensitivityanalysis was carried out and the runoff coefficient based on surface type was changed indifferent scenarios.The results of the sensitivity analysis showed that the surface types tiles and sand/gravelhad little impact on the weighted runoff coefficient which in mainly due to the fact thatthe percentage of these surfaces types of the total area is small.The result of the study showed that the largest change in the runoff coefficient occurredin residential areas where the increase in the percentage of impervious surfaces causedby new roofs in the form of porches and garages and from paved or tiled driveways.
Småvatten då och nu : en förändringsstudie av småvatten i Skåne och deras kväveretentionsförmåga
Wetlands play an important role in the ecosystem. They reduce the impact of flow flux in the drainage area, acts as upholder of biodiversity, as an esthetic and recreational component in the landscape and they have the ability to reduce nutrients such as nitrogen, and help preventing eutrophication in costal areas.The number of wetlands in Scania have, due to the intensified agriculture been reduced to maximize the area suitable for crops.However since the mid 80th the consequences of this has been acknowledged, and many wetlands have been restored.This master?s thesis aim to see what impact this development have had on wetlands in Scania over the last 60 years. And also look at some of those factors important for the efficiency of nitrogen removal in wetlands. During the process a detailed manual for inventories of this sort was created.The material used to execute the inventory of wetlands where aerial photographs over Scania from the 1940th, 1980th and 2000.
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.
Forest and water governance in Sweden
Water related problems are highlighted as a challenge to sustainable development and the topic of forests and water is gaining increased attention worldwide. Governing forest and water is a complex issue, as the interactions are affected by policies and actors from multiple levels and sectors. In Sweden, forests cover much of the land and forestry is an important land-use, inevitably impacting the water in the landscape. This study aims to understand and explain the existing governance framework around forestry and water in Sweden. Based on the Policy Arrangement Approach, the study?s research questions focused on the actors involved, the formal and informal rules, the resources and power structures and the discourses related to forestry and water in Sweden.
Heliga vatten : Vattencentrerad kult och vattnets symbolik under Skandinaviens kristnande
This essay aims to explore continuity in water centric cult within the period of the Christianization of Scandinavia (ca 800-1100 AD) and to understand the changing of symbolism of water in pre-Christian cult and early Christian religion. It has previously been thought that Christian priests took over the old holy wells and renamed them after saint, all to ease the pagan people into a Christian lifestyle. But archaeological evidence shows that the cult at these wells, and other water centric sites, where almost completely abandoned a few hundred years before the Christians came to Scandinavia. The Christians should not have felt the need to transform this tradition since it was only practiced in a very small and supposedly private scale. On the contrary, religious activities at these wells seems to increase with the new religion and perhaps this is explained by Christianity itself.
Hårdhetsvariation i grundvatten längs Badelundaåsen mellan Leksand och Avesta
Water hardness indicates the concentration of calcium and magnesium ions in water. Water with high concentrations of these ions is described as hard water and water with low concentrations is described as soft water. Water that is too hard or too soft can lead to technical and economical problems. In collaboration with Midvatten AB, groundwater hardness in the Badelunda esker between Leksand and Avesta has been mapped, and an attempt has been made to explain the variations. For this purpose, different GIS programs, such as ArcView, ArcInfo, IDIRISI, and one geochemical modelling program, PHREEQC, has been used.
Utredning av potentiella hälsorisker i samband med slagg- och slaggvattenhantering vid Hedenverket, Karlstad
In this study potential health risks for employees in connection with handling of bottom ash and bottom ash water at a Municipal Waste Incineration (MWI) plant have been investigated. Air surrounding the bottom ash and the bottom ash water has been examined. MWI is one of the primary ways to manage solid household waste, and bottom ash is the main solid residue produced by the incineration process. Bottom ash constitutes about 15-20% of the original waste. The bottom ash is extinguished in a water bath (bottom ash water).The study was carried out in a MWI plant in Karlstad, Sweden.
Barns tolkning av en modell för vattnets kretslopp : -förståelse och tillämpning
AbstractThe purpose of this study is to find out how pupils give expression of a water cycle model and if the model causes any misunderstanding. Two problems constitute the starting point for this investigation. The first question is: how do the pupils explain the water cycle with the help of the jar model (can of glass). The other question is: can the children see any similarities between the can of glass and our earth. Qualitative semi structured interviews with seven pupils in the ages of 8-9 have been used to show the pupils? own thoughts and how they express them.
Metodik för bestämning av åkerdikens status : fallstudie av ett dike i Munktorps socken
Agricultural drainage ditches are links between fields, lakes and oceans, having the potential to transport e.g. sediment and nutrients. When in a good condition, drainage ditches can act as sinks for e.g. phosphorus and sediments and prevent eutrophication downstream.
The aim of this study was to determine the condition of one agricultural drainage ditch and to come up with suggestions for appropriate measures. The aim was also to determine
which of the ditch?s properties that were possible to evaluate visually, which processes they represented as well as which properties required complementary physical analysis.
This in order to contribute to the work of developing a method for determining the status/condition of agricultural drainage ditches.
Svartgran ? ett alternativ när allt ser mörkt ut? : en kartmodell för att visa lämpliga ståndorter för odling av svartgran
A common problem in forestry is plant death caused by frost. The risk of frost is highest on wind protected, flat or low-lying areas in the terrain. Here you often have regeneration problems with Norwegian spruce which is especially sensitive to spring frost. Swedish tree experiments have shown that the black spruce can be a suitable alternative on these areas, for example on moisture frost prone areas. The species originates from North America and its pioneer tree characteristics make it more frost hardy than Norwegian spruce.
Småskalig vattenkraft vid Olofsfors bruksmuseum : Med faunapassage
In Sweden there are 1894 small-scale hydropower plants in operation, which together generate 4.3 TWh of electricity per year according to Swedish hydropower compound (SVKF, 2011). This corresponds to the annual consumption of about 860,000 Swedish households (based on an annual consumption of 5000 kWh). In the mid-1950s there were around 4000 small-scale hydropower plants in operation in Sweden before cheap fossil fuels and uranium competed with them, in the current situation only 1,894 of these are in use. If slumbering small hydropower plants once again would be taken into use and some new ones are built, we would be able to extract about 7 TWh of renewable electricity from these annually in Sweden, representing about 1.4 million households.The thesis intends to calculate and construct a hydroelectric power plant at the existing dam in Olofsfors and give suggestions on how the power station should run during the time that fish migration is greatest in Leduån.The turbine and generator to the station in Leduån at Olofsfors is designed by the height of the fall and the water flow through the dam. The turbine selected for the station is a CK-1000RM turbine with a 4-pole 250 kW generator from Cargo & power turbine Sweden AB, which is expected to deliver 1.2 GWh per year.
Turbiditet i dricksvatten: mätningar i Luleå kommuns
distributionssystem
Turbiditet är ett mått på partikelinnehåll i dricksvatten samt ett sätt att beskriva vattenkvaliteten. Vattentäkten i Gäddvik, Luleå kommun, har periodvis hög turbiditet. Syftet med examensarbetet är att utreda orsaker till turbiditet i dricksvatten, från Gäddviks vattentäkt till konsumenter i Luleå kommun. Målet är att ge svar på vilken typ av partiklar som orsakar turbiditen. Analyser utfördes före och efter filtrering av dricksvatten.
Optimalt ekologiskt : att gestalta praktfulla parker som kan skötas på ett hållbart sätt
This is a graduate work at the Swedish University of Agricultural Sciences, The Department of Urban and Rural Development, Ultuna. The purpose of this paper has been to find out and describe principles for designing parks that offers good recreational and aesthetical values and require little amount of carbon dioxide emissions during their maintenance. The purpose has also been to see if it's possible to use city wastewater in some extent to assure the plants water supply and to find other means to make it less necessary to use purified water for watering.
Recently made studies as well as older ones show how important green areas are in dense city structures both from a health and a climate perspective. Trees and other plants adsorbs different forms of air pollution and can also lower the temperature in the surrounding area through their transpiration.
Meddelartrygghet : För privatanställda på offentligt finansierade jobb
This paper examines how notifies security looks for private employed workers in jobs founded by the public. The aim is to clarify the legal situation surrounding notifies law, and to analyze possible shortcomings in the law with a focus on the future.Notifies law is based on five cornerstones. Where freedom of information, a right to provide information to the media for publication, ?acquires the right? and protection to be anonymous when talking to the press goes to all workers. The other two pillars, ?a look up prohibitions? and ?retaliatory forbid? apply only to employees in the public sector.
Muddring i Ireån : indirekta effekter på bottenfaunan nedströms
This research aims to investigate the effects that dredging may have on benthic fauna. The dredging took place in the stream Ireån on northern Gotland during the early summer 2010. My area of research was taking place in a scenic area downstream in Ireån close to the Baltic Sea. I chose this area due to the dredging that started just upstream of this area and continued further upstream. Thus it is not the direct impact of the dredging that is the focus for this paper but the side-effect the dredging may have on the area downstream.