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178 Uppsatser om Lake Mälaren catchment - Sida 3 av 12
Igensättning av långsamfilter i Östby vattenverk i Kramfors : studie av påverkande faktorer
Östby waterworks in the community of Kramfors has since 2003 had problems of fast clogging of the slow sand filters. As the clogging appears more often, they must be cleaned more frequently which has made the drinking water preparation difficult. Wintertime it has sometimes been impossible to clean the filters which has led to their closing and this has influenced the water quality negatively.The waterworks is a surface waterworks which takes its raw water from the lake Sjöbysjön. The water is flocculated and filtered in a contact filter with the flocculent EKOFLOCK 91. Thereafter it is alkalinized before it reaches the outdoors placed slow sand filters.
Hållbart jordbruk inom vattenskyddsområde : En studie om Sverige, Danmark, Frankrike och Tyskland
To guarantee protection of our drinking water, water catchment protections are established. These are divided into three different zones and in the first zone it is most likely that an activity, such as agriculture, will contaminate the water resource. Hence the activities are strongly regulated or banned. The EU communion is working towards a sustained water quality through several directives; Nitrate Directive, Waterframwork directives and Sustainable use of pesticide directive. The main purpose is to regulate the diffuse pollution from agriculture.This thesis is about how Denmark, Germany and France are working towards a sustainable agriculture within water protection areas.
Metodikstudie av trollingfisket i Vänern : Jämförelse av fångstrapportering mellan intervjuer och enkäter gjorda på trollingfiskare samt vädrets påverkan på ansträngning
There are five endemic populations of migratory Atlantic salmon (Salmo salar, Salmonidae) and brown trout (Salmo trutta, Salmonidae) remaining in Lake Vänern, whereof two are salmon and three are trout. There is one population of each species in Klarälven, also one of each in Gullspångsälven and there is a population of trout still remaining in Tidan River. Since the beginning of the 20th century endemic populations of salmon and trout have either vanished or declined dramatically due to the construction of hydropower in the rivers around the lake, and still today the future of the remaining populations remains uncertain. To manage salmonid fishes effectively more knowledge of their ecology throughout their different life-stages is needed. A large part of the Lake Vänern salmonoids lives are spent in the lake, where a mayor mortality factor is recreational fishing, especially angling.
Vattenkvalitén i Fredstorpsbäcken - dikad bäck på fastigheten Rämningstorp i Skara kommun :
The estate of Rämningstorp in the region of Västergötland in southern Sweden is administered by the holding trust company Skogssällskapet i Skövde. In 1999 measures were taken by Skogssällskapet to drain the stream Fredstorpsbäcken as a means to increase the forest productivity of the surrounding lands, which are situated on the estate of Rämningstorp. Almost immediately after the drainage, the streamwater turned turbid and a landowner downstream reported the issue to the county administrative board of the region.
The aim of this thesis was firstly to analyse the suspended matter that appeared during summer/autumn and secondly to explain why it came to be. Initial hypotheses for the explanation to the greyish turbid water were that it was either 1) a chemical/biochemical precipitate, or 2) an bacterial/algal blooming.
VISION SJÖSTAD : Flytande Bostäder
Floating housing is a concept gaining ground in Sweden. The dwellings are different in many ways from traditional homes, not only regarding flotation, but also several other technologies. The purpose of this thesis is to emphasize the qualities that exist in living on water. The ambition was to present a proposal for a floating residential area located in Jönköping, containing homes of varying sizes, and to present their technologies. In order to find inspiration and solutions studies have been made on existing floating homes in Stockholm and Kalmar, focusing on their technical and functional solutions.
Årstidsdynamik för kvicksilver i ett sövattensediment :
The limit for mercury in fish, set by health authorities, is exceeded in about half of the lakes in Sweden. Methyl mercury (MeHg) is the most toxic form of mercury and accumulates in fish. Therefore transformation of inorganic mercury (Hg) to methylmercury (MeHg) is an important process that we need to understand in order to possibly counteract the negative effects of mercury in the environment.
The seasonal dynamics of mercury biogeochemistry is likely of great importance for the accumulation of MeHg in the aquatic food web. In thesis the chemical speciation and transformations of Hg and MeHg in bottom waters and sediments is followed in Ängessjön, a small lake located on the east coast in the middle of Sweden. The lake is not directly affected by any industrial pollution and concentrations of Hg in the sediment reflect the atmospheric deposition in this area, as well as processes taking place along the hydrological pathways from soil to lake.
Samples from sediment, bottom- and streamwater were collected in average every second month during the period Feb.
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.
Stopover duration and field site selection by whooper swan (Cygnus cygnus) at Lake Tysslingen, Sweden
The aim of this study was to increase the knowledge about whooper swan (Cygnus cygnus) ecology to enhance the ability to predict and also to prevent the crop damage they cause. The largest proportion of damage in Sweden has been reported at stopover sites during spring migration in February, March and April. Therefore, this study focused on an important stopover site, Lake Tysslingen, situated in south-central Sweden. Specifically, the relation between the duration and period migrating swans stage at the stopover site and mean temperature (measured at three different weather stations) for the years 2001-2010 was studied. Furthermore, the swans´ selection for certain fields in relation to field type, distance to roosting site, a supplemental feeding site and forest edge within agricultural land surrounding the lake was analyzed.
Riktlinjer för enskilt avlopp : Underlag för bedömning av normal och hög skyddsnivå i Köpings kommun
In Sweden, the eutrophication of lakes, water courses and the coastal areas is considered the major threat to aquatic ecosystems and therefore actions taken to reduce the nutrient load to aquatic system including the Baltic Sea has high priority. There are many different sources of phosphorous and nitrogen and domestic wastewater is one contributing factor to the high load. Especially waste water from households that is not connected to municipal sewage treatment or a local small scale plant with appropriate nutrient removal efficiency is considered a problem. These types of households are quite common in rural areas in Sweden and in areas where summer houses has been converted to permanent living. Swedish legislation now permit the municipalities to decide in which areas within the municipality higher demands of the local small scale treatment facility should be met by the households (i.e.
Övergödning av Mälaren : Betydelsen av antalet beviljade dispenser av stallgödselspridning vid Sagån
Eutrophication was recognized in the early 1900's and results in severe algal blooms, increased biomass production and eventually leads to an altered ecosystem. In Mälardalen we find the most eutrophic lakes. Most of the applied phosphorus and nitrogen into seas and oceans comes from agriculture, and the nutrients losses are affected by local weather conditions and soil type. Guidelines for storage and distribution of manure were introduced in the 80s, and the rules were strengthened January 1, 2010. Localities and previous county administrations can whether there are special reasons, grant an exemption for manure application during winter-periods despite the current ban.In this essay I have examined how many exemptions of manure application that has been granted at the Sagån river, and what implications it has for the eutrophication of Lake Mälaren.
Potentiell fosforfrigörelse från sedimentet i Bornsjön, sydvästra Stockholm : The potential leakage of phosphorus from sediment in Lake Bornsjön, south western Stockholm
Lake Bornsjön is situated 30 km southwest of Stockholm in a rift valley lake and consist three basins outstretched in northwest-southeast direction. The surface area is 6,7 km2 with a maximum depth of 18,3 meters, a mean depth of 9,8 meters and a retention time of the water of 6,5 years. The drainage area is 42 km2 and consists mainly of arable land (ca 1000 ha) and productive forestry land (2500 ha), but in the drainage area there are also restored and fairly newly constructed wetlands.Today the Stockholm area receives its drinking water from Lake Mälaren, but if there would be any pollution of this source, Lake Bornsjön would act as the water source. The area surrounding the lake was bought already in 1899 by Stockholm Stad for protection of the lake and was taken over 1993 by Stockholm Vatten AB. It has been a water protection area from 1988 and it was also accepted as a nature reserve in 1995.
Politikers syn på den regionala nivån : En jämförande studie av Västra Götalandsregionen och Norrbottens läns landsting
This study investigates the concept of regionalism in the context of the Swedish middle-level political arena. The used method is qualitative theory and two cases are studied: Västra Götaland and Norrbottens läns landsting.The aim of the study is to see what the politicans think about Swedens regionalization process by compare the views of politicans that function in a region and in a county council. Do they have the same vision about what constitutes a region and which advantages do they see in working in a region or in a county council? Also dimensions about territorially and sectorial autonomy on the regional level, presented by King and Pierre are investigated in order to explain the different regionala organs functioning accordingly to these dimensions.The empirical material that have been analyzed is taken from 17 interviews, from government writings and reports from the SKL association, Sveriges Kommuner och Landsting, about the topic of regionalization and the effects and goals in Sweden.The conclusion of the material is that there is common opinion among the politicans about the goals of a region and also about which areas that can benefit the most from the perspective of beeing a region instead of a county council. When it comes to explaining the dimensions of territorially and sectorial autonomy the results have shown that the region has the most both territorially and sectorial autonomy, which is due to the regions rightfullness to taxation right, which is high in the region and ensured by a strong catchment area.
Bakteriell produktion i humösa istäckta sjöar i norra Sverige
The main purposes of this study were to 1) quantify bacterial production in winter during ice conditions, and 2) to compare these production measures with values measured from summer and open water conditions in three humic lakes situated in northern Sweden. Another purpose of this study was to 3) examine whether clear-cutting significantly affected bacterial production or water chemistry in two lakes situated in catchments were a large part of the forest had been removed through logging compared to an undisturbed reference lake. In winter (March/April 2014), the bacterial production ranged from 0, 7 - 2, 2 µgC/L/day and in the summer of 2013 the production values was 4 ? 10 times higher. The main reason for lower bacterial production in winter was ascribed to lower water temperatures as well as to older and more recalcitrant DOC, as there were no significant differences in total dissolved nitrogen or DOC concentration or -quality, that could explain a lower production compared to summer.
?Ett indiskret brott mot god takt och ton? : Om arkeologi och samtiden utifrån fångstmarksgravar
Hunting ground graves were distinguished as a separate category during the 1930s. Â Â Â Â There is however no clear definition of what a hunting ground grave is. They have been constructed over a large area over a long period of time (200 BC-1200 AD) and their morphology varies.This paper investigates how the archaeologists have discussed the hunting ground graves since they were distinguished as a separate category until today. It investigates what concepts that have been used to define and categorize the graves as a group. It also investigates if the choices of concepts are depending on a broader societal perspective.To find the answers to these questions two surveys have been done.
Planering av en del av Vätterstranden i Jönköping
This essay will discuss the process of drawing a restaurant ? the position of the house lot, requirements from the authority and architectural quality.During the summer months are many people celebrating their spare time in the beach in Jönköping, by the shore of Lake Vättern. There is some existing buildings in this area that is not used by a general public. In cooperation with the municipality of Jönköping and a person who wants to operate a restaurant on the beach, is this essay a proposal of how this part of the shore of Lake Vättern can look in the future.The focus of the work is to design a restaurant. This is made on the basis of the interviews that have been made with the operators of the area and a thought building, and from the existing rules of the performing and designing of a restaurant.The planned restaurant is placed in an area where it today is a public toilet.