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43 Uppsatser om Catchment - Sida 3 av 3

Karakterisering och klassificering av gotländska ytvatten enligt ramdirektivet för vatten

In this study the practical work with the EU Water Framework starts on the island of Gotland. 33 lakes and 32 streams have been characterized and classified regarding to their ecological status. The aim with the characterisation is to create a uniform discription of all waterbodies and a comparable estimation for the future. The aim with the classification is both to study the waterbodies ecological status and to gain knowledge of where the resources should be concentrated so that the ecological status in all waterbodies will be good in 2015.The characterisation has been done according to the EU Water Framework Directive, and the factors that have been applied are the mean depth and area of the lake. The length and size on the Catchment area are the factors that have been used on streams.

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.

Recipientundersökning av Ensjön : Bedömning av sulfidmalmgruvan Enåsens eventuella påverkan på sjöns vattenkvalitet

Ensåsengruvan is a mine situated within Ljusdals municipality in central Sweden. Themine was in use from 1984 to 1991 and has since been undergoing a remediation program. Mine tailings from sulfide rich ore is a potential environmental hazard due to its tendency to cause acid waters and heavy metal leakage. Lake Ensjön is situated one kilometer from the mine area. Due to the hydrological conditions it was not expected to receive inflowing water from the mining area.

Kväve i Östra Mälaren : hur kunskap förvaltas och används i tillståndsprocesser

The nitrogen cycle in freshwater bodies is complex and consists of many separate processes affected by a number of important factors for example oxygen concentration in the water, temperature and circulation. Knowledge of the different components of the nitrogen cycle exists; however, a complete and comprehensive picture is difficult conceptually as well as theoretically. The available literature illustrates that the research on nitrogen and the related freshwater processes is still associated with high uncertainty of how much of the supplied nitrogen from the Catchment is transported with the water versus and how much is lost due to denitrification, sedimentation or uptake by plants. This report is an interdisciplinary survey of Nitrogen discharge permitting. The research focuses in particular on the decision-making process, the levels of scientific standard and the administrative framework.Application for Nitrogen discharge permits are decided by the Environmental Court with council from their own experts as well as relevant government authorities and organisations.

Vattenkvalitet och risker vid ändrat intag för vattenförsörjning i Västerås

Water is the most essential resource for life. In cases where drinking water is processed from surface water it is important to ensure the raw water is of good quality, and is suitable for processing through the water treatment plant.The drinking water for Västerås is sourced from Västeråsfjärden, in the western side of Lake Mälaren. The city itself is home to marinas, ports, a wastewater treatment plant, the Svartån outlet, sewage pumping stations and stormwater outlets. Because of the negative effects these activities have on surface water quality, Mälarenergi AB is interested in relocating the raw water intake point to Granfjärden, 10 km east of Västeråsfjärden. At Granfjärden the intake point would be less exposed to the activities in Västerås, and could be placed at a greater depth, resulting in better water quality.In this Master?s thesis the water quality and the pollution risks at Västeråsfjärden and Granfjärden sites are compared.

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.

Tillämpning av GIS-analyser i MKB

The reason for performing an Environmental Impact Assessment (EIA) is to incorporate environmental concern in different kinds of plans and projects. The purpose of such an assessment is to identify and describe direct, indirect and cumulative environmental impacts.Geographical Information System (GIS) is a tool that can be used to combine spatial extension of both sensitive areas and different environmental impacts in a quick and easy way. Because of that, descriptions of environmental impacts and motivation of different standpoints on a specific issue can be more correct and easier to make if GIS is used as a tool.Hence, GIS can contribute to improve the quality of Environmental Impact Assessments. If the benefits of using GIS are to out weight the costs, geographical information of satisfactory detail, actuality and accuracy need to be available at reasonable prices.In this paper, case studies are carried out for three different geographical analyses to investigate the use of GIS as a tool in EIA. From these case studies, more general conclusions about the benefits and limitations of using GIS for Environmental Impact Assessments are also drawn.

Modellering av vattenflöden samt kväve- och fosforkoncentrationer från Krycklans avrinningsområde med HYPE-modellen

HYPE-modellen utvecklades som ett hjälpmedel för att uppfylla målet om att alla svenska vattendrag ska ha uppnått åtminstone god ekologisk status år 2015, enligt EU:s ramdirektiv för vatten. I HYPE-modellen delas avrinningsområdet in i markklasser, som definieras utifrån kombinationen av jordart och markanvändning/marktäckeklass. I modellen finns det många parametrar. Vissa av dem är generella för ett större område eller kan hämtas ifrån tidigare forskning, medan andra måste kalibreras för varje avrinningsområde. De parametrar som kalibreras beror i de flesta fall antingen av jordart eller av markanvändning eller marktäckeklass.Syftet i den här undersökningen var att kalibrera HYPE-modellen för ett mindre avrinningsområde samt undersöka avrinningsvägar och utvärdera den utförda kalibreringen.

Referensvåtmarker för uppföljning av växtnäringsretention i anlagda våtmarker

One of the environmental problems today in seas, lakes and streams is eutrophication. This is often caused by nutrients such as phosphorus (P) and nitrogen (N) that leak from agricultural areas. A measure to partly prevent the nutrient discharge is to construct or restore wetlands.In order to control the efficiency of nutrient reduction of existing wetlands in the county, the administrative board in Västra Götaland wants to find different criterias for reference wetlands. These reference wetlands should represent other wetlands and be used in future evaluations of reduction of nutrients and design of constructed wetlands. According to the administrative board in Västra Götaland the reference wetlands should have a Catchment area of about 50 hectare consisting of at least 70 % arable land, to represent wetlands created to remove nutrients.

Bestämning av vattendelare i urban miljö : Metod för avgränsning av avrinningsområden i ArcGIS utgående från dagvattensystemet

Växande städer leder till att naturmark omvandlas till stadsmiljöer. Det skapar mer hårdgjorda ytor och därmed ökade volymer dagvatten som behöver hanteras. Modellering av dagvattennätet används ofta för att bedöma kapaciteten och risk för översvämningar. Avrinningsområdets storlek är en avgörande parameter för att bedöma hur mycket vatten som kommer till en viss ledning. Traditionellt har automatisk bestämning av avrinningsområden gjorts enbart utifrån topografin.

Identifiering av fosfatfosfors käll- och flödesfördelning i ett litet jordbruksområde

Eutrophication of lakes and streams are nowadays a well known environmental problem and implies an enrichment of the nutrients phosphorus (P) and nitrogen (N). Phosphorus is considered to be the most important component for the growth of aquatic plants and leads in too large quantities to an intensification of growth. Phosphate (PO4) is the fraction of phosphorus that can easiest be taken up by plants and thus have the greatest impact on eutrophication. Increased plant growth in lakes and unfavorable conditions for aquatic animals are two examples of negative consequences. A significant portion of the increased nutrient supply to nearby water can be derived to phosphate leaching from agricultural areas, where private sewers and agriculture is two main sources.

Elevers attityder, kunskaper och beteenden : inom kunskapsområdet konsumtion och ekonomi i Hem- och konsumentkunskap

SammanfattningKonsumtion och ekonomi är områden som på olika sätt påverkar människors liv. Forskning visar att värderingar, identiteter och idéer grundas på konsumtion. Syftet med denna studie var att undersöka elevernas attityder, kunskaper och beteenden inom konsumtion och ekonomi som är ett kunskapsområde inom ämnet hem- och konsumentkunskap. Författaren var även intresserad av att undersöka om det fanns skillnader mellan två skolor bland elever i årskurs nio som skiljer sig åt vad gäller upptagningsområde och skolans geografiska läge. 153 enkäter delades ut och resultatet analyserades med dataprogrammet IBM Statistics Version 20 (SPSS 2010).

Challenges and incentives for sustainable manure management in Russia

The Baltic Sea is threatened by eutrophication that largely is due to nutrient leaching from farmland within the Catchment area. To solve this problem the surrounding countries cooperate within various configurations such as HELCOM and the EU-financed project Baltic Compass. Poor manure management in Russia has been discussed frequently the last couple of years. A literature review of different types of reports and legal acts is the core of this degree project which has been performed in connection to two ongoing research projects financed by EU (Baltic Compass) and SIDA. It is supplemented with interviews with Swedish agricultural consultants and travel reports from two occasions when I had the opportunity to discuss with Russians active within the agricultural sector. Different hypotheses were investigated and discussed. The environmental debate in Russia is quiet and there is a widespread approach that economic profit always trumps environmental concern ? a Soviet heritage that influence the Russian agriculture considerably. The Russian legal acts on stable manure management focus mainly on sanitary questions and only secondary on nutrient leaching.

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