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113 Uppsatser om Changes in precipitation - Sida 2 av 8

Sitkagranens potentiella merproduktion jämfört med vanlig gran i Hallands län

Sitka spruce (Picea sitchensis) is not considered to be a native species to Swedish forests. It´s origin is the pacific coast of Northern America, an area that is dominated by a coastal climate which makes it likely to believe that it would be well suited for growing in the south-west of Sweden. This study aims to investigate the gain in production that can be reached by growing sitka spruce instead of Norway spruce (Picea abies) in the county of Halland. A regression model based on data from forest experiments was produced to explain the gain in production. This model was based on elevation and annual precipitation. The model was then used to create a map layer in arcGIS that shows the gain of volume in comparison to Norway spruce in percent. An analysis was carried out to find what share of the forestland in Halland county that fell into four different classes of production gain.

Avskiljning av ammoniumkväve och fosfatfosfor i reaktiva filtermaterial : skak- och kolonnförsök

In Sweden more than 400 000 private households have not yet sufficient wastewater purification. These effluent is considered as an increasing problem and many onsite purification methods have been studied. In this investigation, the method of reactive bed filters have been tested by column and batch experiments. Five different kinds of filter materials with reactive surfaces have been studied concerning their capacity to absorb ammonium and phosphorus from wastewater. The materials that were examined are Filtra N, wollastonite Filtra P, blast furnace slag and Polonite®.

Förekomsten av utfällningar på måleriskikt En studie av Holdhus kyrkas predikstol

Uppsats för avläggande av filosofie kandidatexamen iKulturvård, Konservatorprogrammet15 hpInstitutionen för kulturvårdGöteborgs universitet2013:11Förekomsten av utfällningarpå måleriskiktEn studie av Holdhus kyrkas predikstol.

Metaller i dagvatten - Effekter i recipient : En analys av koppar, kdamium och zink i dagvatten från en parkering i Halmstad, Sverige

When stormwater occurs near human activity the water gets polluted. The purity and composition vary widely depending on the types of activities in the area, the type of surface the water comes in contact with, precipitation and many more parameters. It has long been known that stormwater quality can affect both human health and the environment as stormwater is a major contributor to pollution of receiving waters.A human activity that has an impact on the environment in several different ways is traffic and stormwater is no exception. Airborne gases that react with precipitation, oil leaks and fuel systems that drops down on the ground, metals from brake linings and rubber particles from tire wear are some of the aspects you have to take into account when categorizing the relationship between traffic and polluted stormwater.In this project, stormwater samples from a parking lot in Halmstad, Sweden were collected and analyzed with an atomic spectrophotometer. The presence and relationship between copper, cadmium and zinc with different rainfall parameters have been studied.

Hussvamp : Skadeverkan och tänkbar ökning i Kronobergs län

Serpula lacrymans infestation has become an increasingly common problem, and is usually perceived as a tip of an iceberg.During the 21st century there has been a perceived increase of damage caused by serpula lacrymans, at AB Mats Fransson Saneringstjänst ? Anticimex in the county of Kronoberg. A similar increase has also been noted by employees at the offices in Kalmar, Karlstad, Piteå, Stockholm, Malmö, Söderhamn, Halmstad and Visby.The methods used to collect data for the project has been interviews with a number, for the project, relevant key persons, such as analysis engineers at Trygghansa and Anticimex, as well as personnel at the botanical institution at Gothenburg University and the Botaniska Analysgruppen in Gothenburg, further statistics from SMHI and analyses of reported instances of infestations have been used.The majority of the people interviewed believe that the increase is caused by renovations of old houses, higher precipitation during the summer months, as well as a moister climate and warmer winters. The latter can also be gleaned from statistics from SMHI concerning temperature, precipitation, and relative humidity.Analysed damage reports show that the most common cause for the infestation is ground moisture, even when combined wooden materials.Older houses that where built around 1900 are the ones most frequently infested with serpula lacrymans. The part of the building most frequently infested is the foundation, where cellars and suspended foundation are the most common types to be infested.

Inverkan av nederbörd, temperatur och frost på årsringens egenskaper hos boreal tall (Pinus sylvestris L.) :

The wide distribution range of our boreal pine (Pinus sylvestris L.) provides a great variation in growing conditions and climate/weather factors that influence the wood development of the trees. A great number of extensive studies have been conducted over the years in order to clarify growth trends of this and other species over more or less wide-ranging areas. In this thesis effects of weather factors were instead compared between different forest stands from the about same geographical location. The effects of precipitation, temperature and frost on the year ring characteristics of pine were studied in the research forest of Svartberget Vindeln, in northern Sweden. The stands differed in site index and silvicultural treatment; fertile ? high stem density, fertile ? low stem density, poor ? high stem density and poor ? low stem density.

Membranbioreaktorteknik- en framtida lösning på Lundåkraverket? : Membrane bioreactors- A future solution at Lundåkra wastewater treatment plant?

Membrane bioreactors (MBR) combined with biological phosphorous treatment (Bio-P) has been investigated if that could be an alternative to the future expansion with conventional active sludge treatment at Lundåkra wastewater treatment plant (WWTP) in the proximity of Landskrona, Sweden.The results showed that the surface demand in the biological treatment will be reduced with 67% with the MBR-alternative compared to a conventional activated sludge process. The nutrient removal in the MBR-solution was decreased or unchanged for nitrogen-, phosphorous- and organic parameters. However, the energy demand will increase with an estimated cost of approximately 1 million SEK annually. Moreover, the extra chemical consumption is estimated to cost 370 000 SEK annually.The disturbances caused by filamentous bacteria such as sludge dispersal could be resolved with MBR-technology because the membranes are not affected by these organisms. The Bio-P process combined with MBR-technology works if the wastewater recirculates from the membranes to an aerobic zone.In the proposal, there will be a new pre-treatment step, for instance hole screens.

Induktiv provning av ferritiskt rostfritt stå

The report examines the factors which may be a contributing cause to the problems that are present when ferritic stainless steel are eddy current tested in a warm condition. The work is carried out at Fagersta Stainless AB in Fagersta which manufactures stainless steel wire. In the rolling mill there is an eddy current equipment for detection of surface defects on the wire. The ferritic stainless steels cause a noise when testing and this noise complicates the detection of defects.Because of this, a study was made of how the noise related to factors such as steel grade, temperature, size and velocity. By observing the signal and with the possibilities to change the equipment settings the capability to let a signal filter reduce the noise level were evaluated.

Markavvattningsföretagens geografi och konsekvenser i Trosaåns avrinningsområde

Agricultural drainage is widely used to manage the amount of water in the ground in order to improve conditions for cultivation. However the effects of drainage companies on water regimes are considerable leading to runoff changes such as altered stream flows, peak flows and water levels. In a greater extent this could imply an increased risk for floods along affected watercourses. This study analyzes the extension of agricultural drainage within the drainage basin of Trosaån in Sweden by ArcGIS mapping. In a statistical analysis, historical variation in streamflow in relation to mean precipitation and mean temperature are investigated for the study area.

Återvinning av näringsämnen från hushållsspillvatten med omvänd osmos

Hammarby Sjöstad is a new district in Stockholm with high environmental standard. Stockholm Water Company evaluates a local wastewater treatment plant with cutting edge technology. The first step is an experimental treatment plant (Sjöstadsverket) with four parallel lines of treatment, each with a capacity to treat wastewater from 150 persons. Within the membrane technology subproject the possibility of using reverse osmosis (usually called RO) to regain nutrients is examined.Reverse osmosis separates the incoming water in a clean permeate and a concentrate that, as the name indicates, is a more concentrated version of the incoming water. Using this method in wastewater treatment, a solution high in nutrients can be obtained without the use of chemical precipitation agent and with no production of sludge.

Rening av metallhaltigt avloppsvatten : En teknisk/ekonomisk utvärdering av reningsmetoder för metallhaltigt avloppsvatten

This Master?s Thesis aims to investigate and assess the methods used to decrease the discharge ofmetals, primarily copper, from the water purification plant at Assa Industries plating factory inEskilstuna.Literature studies of the purification methods precipitation, ion exchange, evaporation, reverseosmosis and electrolysis has been done to appraise the adequacy of the technique. Thesetechniques are commonly used for purification of industrial waste water.Assa has four plating lines: the Trumline, the big Zinkline, the new Zinkline and the Decorativeline. The new Zinkline is the most modern of the four lines and purification is done byrecirculation over an ion exchange unit. The demand for fresh water is thereby heavily reduced.The Trumline, the big Zinkline and the Decorative line all use older techniques.

Förutsättningskontroll och nedbrytningstest på oljeförorenad mark : Preem 2, Karlstad

More frequent and intensified rainfalls are expected to occur due to climate change in the nearfuture. This together with a higher proportion of paved areas increases the pressure on today?sstorm water systems (Risinger, 2014; Boverket, 2013; Stahre, 2006). Traditional storm watersystems (i.e. underground pipe systems) have during last decades started to be questioned(Olshammar & Baresel, 2012).

Översvämningskartering av Vombs ängar

Vomb meadows is an area well knows for its rich bird life. During the 19:thcentury until mid 20:th century, the meadows were flooded annually in order toincrease the hay yield. The river Klingavälsån situated along the west side of themeadows, used to be a shallow river, meandering across the landscape. In the1940?s the river was straightened and made deeper.

Hinder & möjligheter med dagvattenhantering : Fallstudier över Linköping och Norrköping kommuns arbete med alternativ dagvattenhantering

More frequent and intensified rainfalls are expected to occur due to climate change in the nearfuture. This together with a higher proportion of paved areas increases the pressure on today?sstorm water systems (Risinger, 2014; Boverket, 2013; Stahre, 2006). Traditional storm watersystems (i.e. underground pipe systems) have during last decades started to be questioned(Olshammar & Baresel, 2012).

Optimering av biologisk fosfor och kvävereduktion i ett reningsverk för hushållsspillvatten

In connection with Henriksdals wastewater treatment plant (WWTP) a smaller plant is situated called Sjöstadsverket where new methods for wastewater treatment are tested and evaluated in different process lines. On one of the lines experiments with enhanced biological phosphorous removal (EBPR), have been carried out to evaluate if it is a good alternative to traditional chemical phosphorus removal. This thesis evaluates the results from the experiments conducted during fall 2005.The incoming water from Hammarby Sjöstad consists of only household wastewater, which gives a wastewater with high concentrations of nutrients and organic carbon. This is partly positive, because one of the limiting factors for effective biological phosphorus removal is the lack of easily biodegradable organic carbon. The high concentrations of ammonium and phosphorus demand a high reduction to achieve the requirements of outgoing concentration.To optimize the process experiments with different recirculations and different aeration techniques have been made.

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