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1514 Uppsatser om Sub surface flow wetlands - Sida 1 av 101

Bottensubstrat och dess inverkan på reducering av BOD5, COD och TKN i lakvatten genom konstruerade rotzonsanläggningar : En pilotstudie vid Univates, Lajeado ? RS Brasilien

Treatment wetlands been showed efficient for reducing pollutant in waste water. In Lajeado ? RS, Brazil the landfill has poor leachate water treatment. It is necessary to supplement the treatment plant because they need to reduce BOD, COD and nitrate of the water going to recipient. A subsurface flow wetland (SSF) can be a good choice.  In order to be able to design an efficient SSF it is important to understand how the grain sizes of a substrate affect the reducing of pollutants in waste water.

Translokation av större vattensalamander : -bevarandestrategi eller riskåtgärd?

This study evaluates the retention of nitrogen and phosphorus in four newly constructed wetlands in the municipality of Falkenberg, Sweden. The four wetlands have been selected because they have been specifically constructed with the aim to reduce nitrogen and phosphorus in farming areas. The process of selecting the specific wetlands has been done in collaboration with the county administration in Halland. Through field studies in collaboration with the landowners where the wetlands are sited, the areas that provide the wetlands with water were determined. The size of these drainage areas were determined in a GIS computer program. The type of land use within the drainage areas was also determined.

Näringsämnesretention i fyra nyanlagda våtmarker i Falkenbergs Kommun

This study evaluates the retention of nitrogen and phosphorus in four newly constructed wetlands in the municipality of Falkenberg, Sweden. The four wetlands have been selected because they have been specifically constructed with the aim to reduce nitrogen and phosphorus in farming areas. The process of selecting the specific wetlands has been done in collaboration with the county administration in Halland. Through field studies in collaboration with the landowners where the wetlands are sited, the areas that provide the wetlands with water were determined. The size of these drainage areas were determined in a GIS computer program. The type of land use within the drainage areas was also determined.

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.

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.

Uppskattning av Ytkurvatur och CFD-simuleringar i Mänskliga Bukaortor

By applying a segmentation procedure to two different sets of computed tomography scans, two geometrical models of the abdominal aorta, containing one inlet and two outlets have been constructed. One of these depicts a healthy blood vessel while the other displays one afflicted with a Abdominal Aortic Aneurysm. After inputting these geometries into the computational dynamics software FLUENT, six simulations of laminar, stationary flow of a fluid that was assumed to be Newtonian were performed. The mass flow rate across the model outlet boundaries was varied for the different simulations to produce a basis for a parameter analysis study. The segmentation data was also used as input data to a surface description procedure which produced not only the surface itself, but also the first and second directional derivatives in every one of its defining spatial data points.

Batch flow behandling och kontinuerligt flöde av lakvatten i en rotzonsanläggning : En jämförande studie i pilotskala

This report deals with the performance of a batch flow treatment of landfillleachate compared with a continuous flow system. The parameters in focus were total Kjeldahl nitrogen (TKN), BOD5 and COD. The pilot-scale experiment used eight barrels with a volume of 150 liters. Each barrel was constructed differently concerning its flow, its bed material grain size and its presence of plants or not. Four of the barrels worked in batch mode, thus four in continuous flow mode.

Våtmarker för näringsretention i Lillån : var bör de ligga och vilken effekt kan vi förvänta

Construction of wetlands in the agricultural landscape may reduce nitrogen and phosphorus transfer to streams, thereby reducing the eutrophication of lakes and seas. The agriculturalstream Lillån, a tributary to stream Sagån, ends up in Lake Mälaren and is transporting large amounts of these plant nutrients. The aim of this study was to estimate how hypothetical wetlands of different size and location may reduce nitrogen and phosphorus load from stream Lillån. Estimated nutrient retention in several small wetlands was compared to retention in a single large wetland based on existing data from the agricultural stream and from a nearby smaller stream. Retention in the stream was suggested to decrease along with the nutrient concentration in the water.

Betydelsen av anlagda våtmarkers area och ålder för förekomst av sjöfågel inom Linköpings kommun

The aim of this study was to examine what impact restored and constructed pounds and wetlands have on waterfowls in the area of Linköping. The birdlife in five constructed wetlands werechosen to investigate if specific factors like age, size and vegetation affected the avian diversity in wetlands. Also, extra focus has been given to the threatened Horned Grebe (Podiceps Auritus), breeding in the studied area. The results showed that the number of species as well as individuals of waterfowl and Horned Grebe changed over time in what might be a result of succession in the wetlands. Comparing the number of birds to the size of the wetlands showed a clear correlation. Larger areas inhabited greater numbers of species and individuals.

Produktionsvåtmarker mot övergödning

In ambition to produce more and better harvests, artificial fertilizers are used to produce a better growth of crops in the agriculture landscape. This contributes to leakage of nutrients. Our forests also exhibit a leakage of nutrients. Air pollution contributes to more nutrients. High precipitation with high water flows as a consequence seems currently to occur more frequently in the county of Halland.

Amfibier i nyanlagda våtmarker : En fältstudie i Laholms jordbrukslandskap

Many species of amphibians are threatened both in Sweden and globally. The causes are many and a main factor is habitat alterations which often results in populations being isolated. Changes in the agricultural landscape have among other things resulted in small water bodies being filled and dried out and that has severely affected the Swedish amphibians. Swedish amphibians are depended upon small water bodies for their reproduction. Wetlands have been constructed to reduce the impacts of the eutrophication in the Laholm bay.

En uppföljning av floran i Enköpings vattenpark : kan anlagda våtmarker med vattenrening som huvudsyfte bidra till naturvård och biologisk mångfald?

Wetlands are important ecosystems and form habitat for both common and threatened species. In Sweden, as well in many other places on earth, there is a lack of wetlands. There is an expressed will to adjust this lack through restoration of wetlands with reduced function and through construction of new wetlands. Follow-ups and evaluations are important steps to optimize these actions. The wetland Vattenparken was constructed 1999 ? 2000 for treatment of surface water.

Näringsretention i återskapad våtmark på betesmark : studier av en mad vid Bornsjön

It is important to construct or recreate different types of wetlands and study their retention of nutrients, since knowledge of their effectiveness in this matter is poor. In 2003 a wetland was constructed on an old meadow on the western shore of Lake Bornsjön in central Sweden. The main purpose of the wetland was to reduce the amount of phosphorus entering the lake, which is the back-up water supply for Stockholm when the city cannot obtain water from Lake Mälaren. Large areas around Lake Bornsjön consist of agricultural land and the nutrient concentrations in the inflows to the lake are usually relatively high (approx. 1 mg/l total nitrogen and 0.05-0.1 mg/l total phosphorus).

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.

Ombyggnation, från sågverkslokal till restaurang. antonio ziakoulis

Pharmaceuticals that are found in marine ecosystems are a threatening environmental concern, which is known to harm both animal and plant life. One of the reasons for this problem is that the waste water treatment techniques are not optimized to clear waste water from its pharmaceuticals contain. In this master thesis four Swedish treatment wetlands were studied, and their ability to reduce numerous pharmaceuticals in waste water. The four treatment wetlands that were studied were those in Oxelösund, Trosa, Nynäshamn and Eskilstuna. Two ecotoxicological tests and chemical analysis were used.

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