Common species of freshwater mussels may, like the freshwater pearl mussel (Margaritifera margaritifera) have a drastic decline in number and there is several reasons, like sedimentation, a decline of host fishes, introduction of alien species, nutrition leakages from agriculture and pollutants of medic drugs and poison. Ann Gustavsson made in the year of 2007 a study over rejuventation of freshwater great mussels in nine watersystems and considered that the rejuventation within the populations were all along the line poor. This study orients from her work and points to determine if there is a connection between the poor juventation and pollution of nitrogen and phosphorous from industries and private sanitations. The study was performed with the software program ArcGIS9.2 to take out drainage areas for the concerned habitats and contact was made with the concerned authoritys. When it comes to supervision of private sanitations is it the countys and for industries is it the county administrative board.

This thesis work was made for Södra Cell Mörrums bruk in Blekinge. The purpose of the work was to develop a computer model in the simulation program Extend for the removal and balance of organic oxygen consuming substances, measured as COD (Chemical Oxygen Demand), in the new biological treatment plant in the mill. The plant produces two different pulp products, TCF- (Totally Chlorine Free) pulp and ECF- (Elementary Chlorine Free) pulp, for sale. The different bleaching procedures affect the characteristic of the wastewater and thus the effectiveness of the biological treatment plant.In the model that was developed the COD in the wastewater was divided into five different COD-fractions: soluble easily degradable (SS), soluble hardly degradable (SR), soluble inert (SI), particulate inert (XI) and particulate biomass (XB). To create the model FlowMac? was used as a base.

The aim of this study was to examine the amounts of heavy metals in the sediment of a wetland constructed for stormwater treatment. The wetland is called Vattenparken and is located in the city of Enköping. The heavy metals which were analysed were Pb, Cd, Ni, Zn, Cu, Cr and Hg. The total metal concentrations were determined using HNO3 chemical extraction. From 8 sampling sites 5 sediment cores were taken.

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.

AbstractSurface-water includes different kinds of pollutants from traffic and roads. To prevent these pollutants to reach nearby lakes one can construct surface-water ponds on locations with heavy traffic. At Bergviks shopping centre in Karlstad, two ponds, one smaller and one bigger has been constructed in order to decrease the pollutant pressure from the receiving waters of Kattfjorden. Several heavy metals are essential for plants and animals in low concentration but when they occur in higher concentrations, they become toxic to the organism. The larger pond at Bergviks shopping centre has a sedimentation function so the heavy metals sink to the bottom thereby not releasing directly in to Kattfjorden.

B-ESR är en ospecifik inflammatorisk markör vilken fungerar som en indikator på förekomst av kroniska infektioner samt maligna tillstånd. Metoden för analys av B-ESR som används i idag är modifierad enligt Westergrens metod, vilken bygger på att fyra delar blod späds med en del isoton citratlösning i ett vacutainerrör (100×9mm). Provröret blandas noga, placeras vertikalt i rumstemperatur varefter hastigheten för sedimentation av erytrocyterna mäts i mm efter 60 min. Analysen är tidskrävande och många yttre faktorer kan inverka vilka kan leda till felaktiga analysresultat.Syftet med denna studie var att jämföra instrumentet ESR-100 (Westergren) med Alifax Roller 20 PN som använder en mikrokapilläraggregationsmetod. Genom registrering av den optiska densiteten i relation till koncentrationen av erytrocytaggregat som finns närvarande vid analystillfället konstruerar instrumentet en sedimentationskurva för varje prov.

With the advance of the modern information society, the importance of reliable identity authentication has increased dramatically. Using biometrics as a means for verifying the identity of a person increases both the security and the convenience of the systems. By using yourself to verify your identity such risks as lost keys and misplaced passwords are removed and by virtue of this, convenience is also increased. The most mature and well-developed biometric technique is fingerprint recognition. Fingerprints are unique for each individual and they do not change over time, which is very desirable in this application.

The nitrogen cycle in freshwater bodies is complex and consists of many separate processes affected by a number of important factors for example oxygen concentration in the water, temperature and circulation. Knowledge of the different components of the nitrogen cycle exists; however, a complete and comprehensive picture is difficult conceptually as well as theoretically. The available literature illustrates that the research on nitrogen and the related freshwater processes is still associated with high uncertainty of how much of the supplied nitrogen from the catchment is transported with the water versus and how much is lost due to denitrification, sedimentation or uptake by plants. This report is an interdisciplinary survey of Nitrogen discharge permitting. The research focuses in particular on the decision-making process, the levels of scientific standard and the administrative framework.Application for Nitrogen discharge permits are decided by the Environmental Court with council from their own experts as well as relevant government authorities and organisations.

This study was the first part of a larger project investigating a new surveillance method for Echinococcus multilocularis. In this study we examined livers from wild boar (Sus scrofa), looking for lesions caused by E. multilocularis. E. multilocularis is a small tapeworm which has an indirect life cycle.

Landfill leachate contains a variety of contaminants and is created when rainwater percolates the landfill. For landfill management the leachate is the main issue that can cause problems to the environment. At the landfill of Fläskebo, Renova AB treats the leachate in a local treatment plant. The treatment consists of a chemical treatment step with chemical precipitation, flocculation, sedimentation and filtration, and a final step with a carbon and peat filter. Renova has to ensure that the condition of the leachate reaches the regulation set for the landfill before it is released to the recipient.

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.

Jordbrukets miljöpåverkan genom diffusa läckage och transport av näringsämnen är ett problem som det arbetas aktivt med på nationell, regional och lokal nivå. I Sverige beräknas jordbruket stå för 43 % av de totala kväveutsläppen samt 44 % av de totala fosforutsläppen. Stor del av dessa utsläpp transporteras till havet där de bidrar till övergödning och algblomning. Östersjön är det hav som får ta emot utsläppen då de transporteras hit med floder, åar och grundvatten. Samtidigt anses jordbruket behöva öka matproduktionen för att tillgodose en växande befolkning.

Transformation of inorganic mercury (Hg) to methyl mercury (MeHg) is a biotic process that is proposed to be conducted primarily by sulphate reducing bacteria (SRB). The formation of MeHg is of great interest because it is the mercury species that biomagnifies to the greatest extent in the aquatic food webs; about 90 % of all Hg in fish is MeHg. Our understanding of factors involved in the production of MeHg is very important for making a reliable risk assessment. The purposes of this study were to investigate the different factors that control the solubility of Hg and the production of MeHg in a contaminated lake sediment. The lake Ala-Lombolo, Kiruna municipality, is well-known to be contaminated by mercury from different sources. Sediment cores were sampled at three different locations (N, SW and SE) in the lake and divided in three different layers; 0-5, 5-10 and 10-15 cm.

Running water-pathways have played an important roll in Sweden and frequently been manipulated. One profound change was made during the period of logging when streams were cleared from obstacles as big boulders, sharp bends and side-streams. Dams and different constructions gave control of the stream water and the streams became channel-like with a homogen structure. This interference gave problems for many fish populations and resulted in a shortage of feeding habitat, over-wintering habitat, spawning habitat, unnatural flow regimes, sedimentation, unnatural temperature fluctuations. Many of these historical changes of the watersheds are now subjects for restoration, ie., bring back the streams to what we believed it was before the change. However, what once existed in terms of complexity is now gone and difficult toreplace.

Då naturlig mark görs om till hårdgjord yta i samband med bygge av vägar och bostadsområden ökar flödesbelastningen till närliggande sjöar och vattendrag. Vattenmassorna tar med sig de föroreningar som bland annat finns inbyggda i byggnadsmaterialet, som kommer från trafiken eller från verksamheter som till exempel industrier eller djurhållning. För att förhindra att föroreningarna sprids till de naturliga vattendragen kan åtgärder sättas in för att rena vattnet innan utsläpp till recipienten. Detta kan åstadkommas med hjälp av till exempel så kallade dagvattendammar. Den främsta processen för rening i dagvattendammar är sedimentation. In till dammarna kommer vanligtvis stora mängder partiklar och suspenderat material till vilka föroreningar, som till exempel näringsämnen och metaller, kan fästa.