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1097 Uppsatser om Constructed wetlands - Sida 1 av 74
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.
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.
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.
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.
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.
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.
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.
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.
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.
Reduktion av föroreningar i processvatten från en äggfabrik i Brasilien : Kväve- och fosforrening i anlagda våtmarker.
A water treatment unit consisting of two aeration basins, two settling tanks, a residence basinand a horizontal subsurface flow wetland were used to treat wastewater from an eggprocessing factory in Brazil. The aim of this paper was to determine the efficiency of thesystem in reducing nitrogen, phosphorus, BOD5 and TSS (among other parameters) andgetting a further understanding on different kinds of constructed treatment wetlands as well astheir nitrogen and phosphorus removal processes. The wastewater from the factory consistedof process water from manufacturing and water used for cleaning, no stormwater or sewagewater entered the system. Tests were taken three times a month from October 2013 ?til April2014.
Förslag till kväverening i Forsåsystemet genom våtmarksetablering
The last hundred years humans have drastically changed the amount of available nitrogen in nature. Today human activities release twice as much available nitrogen as all natural processes are doing together. We also have degraded nature´s possibilities to take care of nitrogen through the draining of wetlands and straightening of rivers. In order to regain the potential of nitrogen retention in the water systems there now requires a reshape of the landscape we live in. A planned expansion of the mining activities in Garpenberg, Dalarna, would double the content of nitrogen in the waters below the mine.
Effekten av uteblivna miljöersättningar för anläggning av våtmarker
Environmental subsidies are used as incitements to farmers for development of sustainable land use. In 2014, applications for funding Constructed wetlands were not available. This paper examines the environmental consequences of this lack of funding in one intensively cultivated region Skåne län, southern Sweden.A review of wetland applications between year 2007-2013 show that the average rate of applications has been 31 projects per year with a wetland size of 4,48 ± 1,61ha per project (mean±95% CI). Based on interviews, the result suggests that the lack of funding in one year leads to between 102 and 140 ha of Constructed wetlands that is not built. This correspond to a total loss of increased nitrogen retention capacity between 6,0 and 91,7 tons/year and a loss of increased phosphorus retention capacity between 0,17and 2,1 tons/year in the drainage basins of Skåne.Further the interviews show that continuity of environmental regulations and funding is important for the farmers? interest in environmental measures.It is concluded that the total loss of increased retention capacity is small compared to the annual transport of nitrogen and phosphorus in the drainage basins.
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).
Märstaån ? ett vattenlandskap : Är våtmarker och dammar vägen framåt?
The overall aim is to examine how the European Union Water Framework Directive has affected the local water management in the catchment Märstaån situated in the eastern part of the lake Mälaren river basin, Sweden. The first part of the study gives an historical overview of the area with focus on how the old agricultural landscape was handling the nutrient load from farming activities by means of different kinds of wetlands. By using the concept of the procedural landscape, introduced by Torsten Hägerstrand , together with historical maps with dates starting from the 17th century, the pre-modern landscape is analyzed. The second part is an investigation, based on qualitative data, on how the different actors in the catchment area work together to secure the water quality for the Märstaån river. The analysis shows that the Märstaån catchment river systems are mostly unchanged in the rural areas. The exception is the mainstream section of the Märstaån river running partly underground today and the Halmsjöbäcken river that is heavily affected by the Arlanda airport situated within the catchment area.