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276 Uppsatser om Reactive phosphorus filters - Sida 5 av 19

Internetbegränsning på stadsbibliotek

The purpose of this thesis is to investigate how city librariesmaintain the intellectual freedom in their Internet service. Thediscussion about Internet filters has been quiet in Sweden forseveral years, so I wanted to see if there had been an increased useof filters. I also wanted to see if the city libraries regulated theInternet service in another way. I sent a survey to 100 libraries andgot answer from 83. To explain what intellectual freedom is, I usedStuart Hamilton?s theory about intellectual freedom in the librarycontext.

Har storleken någon betydelse? : En studie av den svenska aktiemarknadens reaktion på varsel om uppsägning av personal

Background: The reasons why this study is conducted is because of the latest recession in the global economy. The current recession has made a lot of companies more aware of its cost, and in order to fit the new harsher economic climate the companies has to be more cost efficient. In order to do so many companies choose to reduce their amount of employees. When this happens in a recession, most of the layoffs are an effect of reactive causes, such as lower incoming orders, and fewer customers. This leads to a problem for the companies that don?t know how these kinds of layoffs will affect the value of the company?s stock.

Naturlig förekomst av arsenik och avskiljning av arsenik från grundvatten : test av olika filtertekniker avsedda för enskilda brunnar

During the last few years the presence of high arsenic (As) concentrations in ground water has been of major concern both internationally and in Sweden. Much evidence has been reported about toxic effects caused by arsenic. The carcinogenic effects and the possibility to measure the toxic impacts at low concentrations made the World Health Organisation (WHO) to reduce the guideline value from 50 to 10 ?g l-1 in 1993. In Sweden the corresponding reduction was implemented in 2003. Several surveys in Sweden have shown that high arsenic concentrations may occur in ground water.

Utvärdering av avloppsvattenreningen vid Hallsta Pappersbruk : Kartläggning av inkommande avloppsvatten och optimering av driftparametrar

Hallsta paper mill uses large amounts of water during the pulp and paper making processes. The wastewater is treated in two separate activated sludge processes referred to as BIO 1 and BIO 2. The main aim is to reduce the organic substance content, measured as COD (Chemical Oxygen Demand) before the wastewater is released into the environment. Since the effluent produced is very rich in organic substances, the addition of nitrogen (N) and phosphorus (P) are necessary to give satisfactory treatment results. Problems with sludge bulking sometimes occur which lead to increased levels of suspended matter and nutrients in the effluent.

Bevattning av lagrat virke vid svensk skogsindustri : omfattning och miljökonsekvenser

Most of the saw and pulp industries have stored wood nearby their production, the main reason is to have a continuous wood flow to the production. Wet storage of wood is of great importance to keep the wood quality. Without water sprinkling the risk of drying outand decomposition through biological activity increases significantly and will result in a negative effect on future production and quality. One drawback of wet storage of wood is the leaching of chemical substances into the surrounding recipient. The log yard run-off contains phosphorus, nitrogen, phenols and organic substances. These substances can cause problems for the surrounding environment. The main objective of this project is to gain an understanding of the wet storage used by the Swedish wood industry and estimate the environmental consequences that run-off water will have on the recipient.

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.

Utvärdering av näringsstatus inför återskapande av kalkkärr vid Hagebyhöga, Östergötland

Calcareous fens constitute a specific habitat which is uncommon in Europe and protected by the EU habitat directive due to its importance to several threatened species. Hagebyhöga in Östergötland is a calcareous fen habitat included in the Natura 2000 Networking Programme. Adjacent to the existing fen, a degraded fen area is situated. The area has been used for agriculture for several years but is now going to be restored to its former state by the county administrative board of Östergötland.When working with restoration of degraded fen areas it is important to aquire knowledge about the chemical soil conditions. Plant growth limited by phosphorus and low fertility are characteristic conditions for calcareous fens, whilst arable land usually is highly fertile and limited by nitrogen.The purpose of this study is to bring forth useful knowledge for restoring the degraded calcareous fen of Hagebyhöga.

Fosforförluster från lantbruket och dess bidrag till övergödning av sjöar och vattendrag i Växjö kommun

The possibility for plants to utilize phosphorus in soil is a prerequisite for conducting agricultural production, both small scale and professional. Spreading of phosphorus fertilizers and manure is therefore seen as a necessity in today's agriculture in order to achieve high yield. Manure management, livestock farming and manure storage could contribute to the eutrophication of lakes and rivers. For instance, when the ground becomes saturated, phosphorus leakage could be seen in surface runoff or in point sources resulting from inadequate manure storage management.In the municipality of Växjö there is still many bodies of water that do not reach the Swedish environmental water quality standard of "good ecological status". This thesis has therefore analyzed the manure management and storage on agricultural farms which may have contributed to eutrophication in the municipality.The method for this thesis was a literature study, a questionnaire survey with 820 receivers and a summary of issued inspection reports from 2013.The results highlight the ways in which agriculture may have contributed to the eutrophication of lakes and streams in the municipality of Växjö.

Jordbrukets påverkan på Östersjön : en jämförelse av indikatorer för att beskriva näringsbelastningen

The Baltic Sea, due to its special conditions, is a unique and vulnerable marine environment. There are many pressures that have an impact on the sea and one of the major problems is the extensive flow of nutrients from land. The most visible effect of the supply of nutrients is the annual algal blooms. One of the main sources of nitrogen and phosphorus supply is agriculture. Nutrient losses from arable land have been increasing as agricultural production has intensified. At the end of the twentieth century an increased awareness of these problems led to the formation of organizations such as HELCOM and Baltic 21.

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.

Vitpunktsförskjutningens påverkan på ICC-profiler vid användande av optiska vitmedel

The connection between fluorescence and color management still is a relatively unexplored area. Thefollowing composition analyses the theory that when printing on fluorescent ink jet paper using ICCprofilesa more yellow print will appear. In theory the ICC-profile compensate for blue light that fluorescefrom the paper with the complementary color, yellow. The human eye apprehands this fluorescentlight as white.When categorizing a number of ink jet qualities some tests to indicate change of color in the final printwere made. Five qualities were chosen for further analyses, each with different white point.

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).

Where has the fertilizer gone? Closing the nutrient budget for a eucalyptus fertilization experiment in southern China

An increasing demand for wood products in China has resulted in large areas invested in fast-growing tree plantations of eucalyptus. Eucalyptus plantations are often associated with an intensive management including fertilization. By understanding the effects of fertilization and where in the ecosystem nutrients are accumulated a more sustainable forest management could be achieved. In this study, a nutrient budget including all biomass and soil components was created for Eucalyptus urophylla. The examined nutrients were nitrogen, phosphorus and potassium.

Närsaltsdosering till luftad damm : en åtgärd för ökad TOC-reduktion hos Skoghalls Bruk luftade damm

In the process of making carton boards into Skoghall Mill, are great quantities of water being contaminated. This water has to be treated before it is possible to release into the recipient, Kattfjorden. One of the contaminations that is important to extract from the wastewater, is organic carbon (measured as TOC-total organic carbon) because microbiological breakdown can lead to the bottom becomig free of oxygen.The wastewater treatment at Skoghall Mill is done through an external wastewater treatment that is located at the factory. The biological treatment (aerated lagoon) is a 140 000 m3 water pool with surface aerator, which is give oxygen to the water. In the lagoon live microorganisms who performs the biggest part of the TOC-reduction.One problem with the lagoon is that the treatment of TOC is considerably worse during wintertime than during summertime.

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.

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