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114 Uppsatser om Floating wetlands - Sida 3 av 8
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).
Bibliotekarieutbildningen vid BHS 1977 t.o.m 1999 En diskursteoretisk studie
The aim of this master thesis is to investigate changes within four discourses identified in the curriculum material of the Swedish library education in Borås Bibliotekarielinjen dating from 1977 and 1985 and its successor Library and Information Science Biblioteks- och informationsvetenskap dating from 1995, 1999. My method used is a text analytic method primarily derived from the discourse theory of Ernesto Laclau and Chantal Mouffe, yet with addition of tools from the critical discourse analysis of Fairclough. By identifying three floating signifiers within the material, i.e information, library, and librarian, and thereafter identifying their fixation, a pattern of resemblance and diversity in the fixating signs appeared between different courses of the curriculum dating from 1999. Hence I could establish an order of discourse consisting of four library discourses, a knowledge organisation discourse, a user discourse, a society discourse and a management discourse. Using this discursive order as a pattern, I could trace these four discourses back in time within the material dating from 1995, 1985 and 1977.
Hänsyn till mark och vatten vid slutavverkning : en fältstudie på känsliga marker
The purpose of this study is to investigate if there is enough consideration taken to sensitive forest areas close to water or wetlands during clear cutting assignments, and to estimate the extent of damage made by forestry machines used at that time. A field and literature study is used to show how to improve and prevent the damage made in the wake of the machines.
This study is made for Sydved, and shall culminate in a policy to prevent ground damage during their clear cutting assignments.
The areas which were part of the field studies were clearcuttings on fine grained soil close to water and wetlands. The purpose was to find out if the water had been affected, what had been done to prevent ground damages and what more could have been done.
The results of the field studies show that more work needs to be done to reach up to expectations. More information about the assignment area, better planning of sensitive regions, and strengthening of the main haul roads with brush are some of the improvements that can be done. There is also a need for more exact guidelines, follow-ups and education for everyone involved to have the same goals and understanding to prevent ground damage..
Vision Sjöhem : Framtagning av förslagshandlingar för flytande bostäder
Stockholm lider idag av omfattande bostadsbrist och ständigt ökande befolkningsmängd. För att möta detta ökande behov av bostäder i Stockholm finns en nödvändighet i att utforska nya vägar till att åstadkomma detta. Här finns en unik möjlighet till en förtätning av staden genom att utnyttja Stockholms stora vattenarealer för att bygga flytande bostäder.Som alternativ till den traditionella byggkonsten ämnar examensarbetet till att demonstrera de kvaliteter som finns med att bo på vatten genom att utforma ett attraktivt bostadsområde med flytande konstruktion. Projektet illustreras i det tidigare hamnområdet vid Liljeholmskajen i Årstadals hamn, Stockholm. För att åstadkomma detta utförs fallstudier på olika typer av flytande konstruktioner som finns på den svenska marknaden för att fastställa de bästa konstruktionslösningarna som leder till färdiga förslagshandlingar.Resultatet visar att ett flytande bostadsområde är genomförbart med dagens teknik som ett sätt att förtäta staden.
? Effekter av en liten biogasanläggning hos småbrukande bönder i Östra Afrika : En studie med utgångspunkt från en småbrukande familj i Kadongo, Kenya
Syftet med den här uppsatsen är att redovisa för de effekter som kan sespå odlingssystem samt livssituation hos småbrukande bönder i Östra Afrika efter ett införande av en liten biogasanläggning kallad "floating drum". Anläggningen genererar rötrester som används som gödslingsmedel i odlingssystem och biogas som bränsle i matlagningssituationer. Resultatet baseras på uppgifter från litteratur, fältstudier och en enkätundersökning. Uppsatsen har sin utgångspunkt från en fältstudie hos en småbrukande familj på landsbygden. Studien genomfördes i ett område som heter Kadongo och ligger i nordvästra Kenya.
Risk för bostadsägare - en analys av risken vid förändringar av ränta och elpris
Since 1996 the Swedish households have ten folded their volume of loans for own homes that is attached to a floating interest rate. Also in 1996 the Swedish electric market was deregulated. These two facts have increased the volatility in the household expenses for these two commodities. This thesis studies the risk for homeowners attached to the exposure against the electric and the credit market. The risk model used is Cost-at-Risk which is usually used by public authorities for analysing the risk involved with national debt.
Evaluation and Comparison of Ecological Models Simulating Nitrogen Processes in Treatment Wetlands,Implemented in Modelica
Two ecological models of nitrogen processes in treatment wetlands have been evaluated and compared. These models have been implemented, simulated, and visualized in the Modelica language. The differences and similarities between the Modelica modeling environment used in this thesis and other environments or tools for ecological modeling have been evaluated. The modeling tools evaluated are PowerSim, Simile, Stella, the MathModelica Model Editor, and WEST. The evaluation and the analysis have been performed using McCall?s factors for software quality (McCall et al, 1977), a correlation analysis and the Constant Comparative Method (Glaser&Strauss, 1999).
Hur påverkar bävern skogens värden?
The activities of beavers in forested landscapes affect both ecological and economical values. The creation of the dynamic wetland mosaic associated to beaver activities can even improve the quality of water and have been documented as an important landscape engineer affecting the environment for many species. The local office of Sveaskog in Skinnskatteberg is responsible for the management of large areas of the forests in the County of Västmanland. In this area one of several company?s goals are to create ten new wetlands in their own forests as a part of cooperation with the Swedish bird society and Swedish wetland association.
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.
Magasin för lagring av vatten och växtnäring
Structural rationalizations and regionalization of the agricultural sector in Sweden has lead to unevenness in thedistribution of plant nutrients. Nutrients are lost from crop producing farms as harvest products are sold, whilefarms with animal production often have manure in excess of their needs. In addition to this the retention ofwater and nutrients in naturally occurring wetlands has decreased due to a reduction of wetlands in number andsize in the agricultural landscape. This increases nutrient levels in agricultural run-off and causes eutrophicationas well as nutrient losses from arable soils. One potential solution to both problems would be to store nutrientrichsurface water from agricultural areas and use it for irrigation of agricultural crops.
Biologiska behandlingsmetoder för rening av rejektvatten från biogasproduktion
In this literature review the characteristics of two free-floating macrophytes, water hyacinth (Eichhornia crassipes) and duckweed (Lemna sp.), and two microalgae, Chlorella and Scenedesmus, have been examined regarding their suitability as efficient nutrient removers in the treatment of wastewater with high levels of nutrients and suspended solids from a biogas plant in Loudden. The needs required for the plants to be able to grow in wastewater and the amounts of biomass they can produce have also been studied. The results show that Chlorella is capable of a very high uptake of nutrients in photobioreactors with high nutrient loadings. With an ammonia uptake maximum value at 10900mg/m2/d Chlorella outshines the other organisms in this study. The test organism that performed the closest to Chlorella in terms of nitrogen uptake was water hyacinth with an uptake about 1602mg/m2/d.
Exosomes as a potential mechanism of intercellular spread of prion protein
Structural rationalizations and regionalization of the agricultural sector in Sweden has lead to unevenness in thedistribution of plant nutrients. Nutrients are lost from crop producing farms as harvest products are sold, whilefarms with animal production often have manure in excess of their needs. In addition to this the retention ofwater and nutrients in naturally occurring wetlands has decreased due to a reduction of wetlands in number andsize in the agricultural landscape. This increases nutrient levels in agricultural run-off and causes eutrophicationas well as nutrient losses from arable soils. One potential solution to both problems would be to store nutrientrichsurface water from agricultural areas and use it for irrigation of agricultural crops.
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.
(O)möjligheternas plats? En diskursstudie av Garaget
A general topic underlying this master thesis is how the public library is being transformed through the subversion and re-articualtion of meaning according to different discourses. The aim of the study can be divided in to levels of analysis. At the first level, the aim is to investigate how categories such as users, needs and vision are articulated in a specific case ?the visionary project Garaget in Malmö, a project which in part include a public library inspired by Idea Store. The next level of analysis sets out to explore how the case of Garaget is related to a totalizing discursive struggle over meaning within the element the public library.
Rimbo våtmark : en förstudie på förväntad kväveavskiljning och lämplig växtlighet
This study was made as a part of a feasibility study on a polishing wetland at Rimbo wastewater plant (wwp) in Norrtälje municipality. The wwp had to decrease the nitrogen discharge to reach the limit 15 mg tot-N/l. The nitrogen in the outlet was mainly in the form of nitrate, hence the wetland mainly ought to support denitrification. The proposed area for the wetland was situated right next to the wwp and was already in the municipalitys posession. One aim of this study was to examine what spieces of plants needed to achieve highest possible denitrification.