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34 Uppsatser om Dredged sediments - Sida 2 av 3
Kloning av möjlig promotorsekvens uppströms kloritdismutas i Ideonella dechloratans.
Perchlorate and chlorate are naturally occurring in the atmosphere, from here it sediments into groundwater and soil. The pollution is increased by discharges of perchlorate and chlorate from agriculture and paper mills. Bacteria capable of reducing perchlorate and chlorate to chloride and oxygen can be used to get rid of these contaminants. However an anaerobic environment needs to be sustained in order for this reaction to be used. For this reduction to work in an aerobic environment as well, a greater knowledge of the reducing enzymes, regulating factors and their corresponding genes is needed.
Geokemisk undersökning vid Rävlidmyrgruvan, Västerbottens län : provtagning, analys och förslag till åtgärder
The mining industry, in terms of ore excavation and metal production, is and has been
important to the Swedish economy. In connection with the ore excavation process, large
amounts of partly sulphidic waste are produced. When the metal sulphides are exposed to air and water they are eventually oxidised, which leads to the formation of acidic water with high concentrations of metal cations and sulphate ions, so called Acid Mine Drainage
(AMD). This water may reach the nearest surroundings and cause negative environmental
effects. By covering the waste with soil or water, the oxidation process can be minimised.
At the Rävlidmyran mine in the county of Västerbotten open pit mining took place between
1951 and 1991.
Sjöundersökning av Naalojärvi
LKAB is an international high tech mineral corporation and a world leading manufacturer of refined ironore products for steal manufacturing and other mineral products destined other industries. LKAB is an international corporation with companies world wide, with it?s main location in the north of Sweden, which is where the iron ore mines and the refining works are located. LKAB?s iron refining process in Vitåfors, Malmberget, is a source of great amounts of waste-rock.
Metodutveckling för analys av klorfenoler i jord samt analys av förorenad jord från ett sågverk
In this final thesis, an existing method for analysis of chlorophenols (CP) in bottom sediments has been updated and adjusted for analysis of chlorophenols in soil. The covalent bonds between the chlorophenols and the soil matrix were broken through basic hydrolysis and the chlorophenols were then separated from the water phase through addition of sulphuric acid followed by ether extraction. The chromatography was improved through extractive acetylation of the chlorophenols.The updated method was then applied on soil samples from a contaminated area (a former sawmill in Hyttsjö, Östergötland, Sweden).The analyse was preformed by GC/MS with respect to 2-MonoCP, 4-MonoCP, 2,4-DiCP, 2,6-DiCP, 2,4,6-TriCP, 2,3,4,6-TetraCP and pentachlorophenol (PCP).Contamination of chlorophenols in nature can be explained by the former use of wood preservative chemicals based on chlorophenols. In the 1960s and the 1970s these chemicals were used in Sweden, but due to their toxicity they were banned by the Swedish government in 1978.In Hyttsjö a pentachlorophenol-based product named Santobrite was used for several years. The concentration of PCP in the soil samples from Hyttsjö varied from 0.2->1.8 ng/mg dry substance.
Storjuktan ? Rekonstruktion av ett sekels kvicksilverbelastning. : En undersökning av kvicksilverkoncentrationer i daterat bottensediment.
The aim of this study was to examine the current and historic mercury(Hg) load of the lake Storjuktan due to its recent exposure to a local potential source of Hg in form of the Sulphide mine Blaikengruvan(2006) and an earlier potential sources of Hg-load, the damming of the lake(1960s). Sediments were extracted using a HTH-sampler, freeze-dried, and analyzed for tot-Hg, LOI and activity of 210Pb and compared to samples extracted prior to the opening of the mine(2006). Constant initial concentration (CIC)-dating model was used for dating the samples. Low levels of Hg (100ng/g) were found throughout the lakes sediment. The highest levels of Hg(220ng/g) was detected at a depth of 4-5cm dating back to the mid 1970:s, suggesting that increased levels of atmospheric Hg rather than damming of the lake has caused the increase of Hg.
Saltvattenpåverkan i enskilda brunnar i kustnära områden : En undersökning av grundvattenförhållandena och riskerna för saltvattenpåverkan i S:t Annas skärgård, Östergötland
Coastal areas are popular for housing, both for permanent living and holiday houses. At the same time, thin sediments and small storage capacity in the bedrock makes the ground water resources limited. The limited ground water resources combined with too large withdrawals of ground water makes salt water intrusion a problem in many coastal areas. This study examine the risk of salt water intrusion in drinking water supplying wells on the island Södra Finnö in S:t Anna archipelago, Östergötland, Sweden. A calculation of the relation between ground water recharge and withdrawal is obtained to analyze the ground water balance in the area.
Fröåtjärns föroreningshistoria : Utredning av hur metallbelastningen varierat över tid med hjälp av sediment som ett naturligt historiearkiv
The metal mining history goes thousands of years back. The downside of the mining industry is the large amount of tailings created during the mining operations. Drainage and leaching of heavy metals from these tailings may cause major environmental problems including acid mine drainage and leaching of heavy metals. This study examines a pond located near an old mining site, where part of the old mining facility has been recently (1990) restored. The objective was to assess eventual metal contamination from historical mining and the recently performed restoration using a sediment core as a natural archive of historical metal inputs to the pond.
Fotogrammetrisk analys av kornstorleksfördelningeni erosionsskydd vid kraftverksdammar
This master thesis was made to investigate the possibilities of using the Matlab-basedsoftware Basegrain to determine grain size distributions of erosion protections onhydropower dams. Basegrain is a photogrammetric tool developed to generate grainsize distributions and other information about coarse flood sediments by analyzing adigital photo of the stone bed. The investigation was made by validating the ability forBasegrain to assess grain size distributions of various materials smaller than the blocksused in an erosion protection by comparing sieving results or manual measurementswith the results obtained by the program. A statistical comparison was then made bycomparing the results from sieving and the program. The possibilities of using thesame method on existing hydropower dams were then investigated by determiningwhether the method was practically viable or not.The results showed that Basegrain generated grain size distributions for coarse gravelthat were very close to the sieving results.
Marktillstånd och borbrist på åkermark planterad med gran i Västerbottens län :
This study was made on former agricultural areas that had been planted with spruce or pine, in the county of Västerbotten. The goal of the project was to investigate suspected deficiency of boron in these areas. Several objects have been reported for possible deficiency and some of these have the characteristic symptoms of boron-deficiency. The hypotheses are that
1) Boron deficiency is present at several of the investigated objects.
2) Planting of forest on cultivated postglacial sediments leads to a successive podzolisation with a decreasing content of organic matter in the mineral soil, due to decomposition, and a decreasing pH in the soil, even on locations that have been added lime.
To be able to confirm or reject the hypotheses a number of tests were performed.
Sedimentprovtagning av dagvattendammar som ett alternativ till flödesproportionell vattenprovtagning
Stormwater run-off from surfaces such as roads or rooftops is often polluted with heavy metals and nutrients. Many of these substances can cause great damage in biota if they end up in the recipient. In Sweden constructed wetlands and ponds for treatment of stormwater are frequently used, since research has shown that these treatment ponds are reducing stormwater pollution considerably to a low cost. The knowledge of these pollutant removal mechanisms and how follow-up and assessment of the ponds should be performed is still limited.To determine the pollutant removal efficiency of the stormwater ponds it is recommended that flow-weighted water samples are collected from both the inflow and the outflow of the pond. This method demands considerable resources of time and money for installations and analysis.
ALK?RR - K?LLA ELLER S?NKA F?R V?XTHUSGASERNA METAN OCH LUSTGAS? Empirisk studie av v?xthusgasutbyte i kustn?ra alk?rr p? den svenska V?stkusten.
Due to global climate change and the rising levels of greenhouse gases (GHG) in the atmosphere, the interest for seeking solutions for mitigation has increased. While much attention has been directed towards technical solutions such as carbon capture and storage (CCS), biogenic carbon sinks has also garnered significant attention. Previous studies have shown that coastal ecosystems such as seagrass meadows and mangroves have a much greater capacity for storing carbon (C) compared to terrestrial ecosystems. That raises the question if other coastal ecosystems, such as coastal wetland forests, that previously haven?t been considered as blue carbon habitats also contribute to coastal carbon sink capacity.
Metodik för bestämning av åkerdikens status : fallstudie av ett dike i Munktorps socken
Agricultural drainage ditches are links between fields, lakes and oceans, having the potential to transport e.g. sediment and nutrients. When in a good condition, drainage ditches can act as sinks for e.g. phosphorus and sediments and prevent eutrophication downstream.
The aim of this study was to determine the condition of one agricultural drainage ditch and to come up with suggestions for appropriate measures. The aim was also to determine
which of the ditch?s properties that were possible to evaluate visually, which processes they represented as well as which properties required complementary physical analysis.
This in order to contribute to the work of developing a method for determining the status/condition of agricultural drainage ditches.
Gimo bruksområde - inventering och riskklassning enligt MIFO fas 1 :
This master thesis encompasses an inventory of the older industrial community of Gimo.
Investigations of the contamination situation for each industrial area were done. A risk
classification according to the Swedish Environmental Protection Agency?s ?Method of
Surveying Contaminated Sites?, phase one, followed. The risk classification was done on
areas of Iron Work, a rockwool industry and a landfill.
Gimo have had iron manufacturing from 1615 until 1945. Gimo have had two blast-furnaces
and two smithies periodically.
Hur förorenad är Tämnaren av Tungmetaller? En undersökning av bottensediment.
Tämnaren är en slättsjö i östra Svealand där ammunition går att finna i bottensedimenten. Ammunitionen härstammar från övningar som Flygvapnet hade över sjön under 1950- och 1960-talen. Sjön är mycket grund och näringsrik och befinner sig i ett område som fortfarande påverkas starkt av landhöjningen orsakad av den senaste inlandsisens tillbakadragande. Detta innebär att Tämnaren växer igen i rask takt och beräknas vara i princip borta om ungefär 600 år. Sjön har ett skyddsvärde dels genom sin rikedom på olika fågelarter som håller till i närområdet men också ett rekreationsvärde för människor i området runt sjön.
Skaftslamkrypa (Elatine hexandra) i Bolmen, utbredning, tillväxt, reproduktion och styrande faktorer
The plants in the genus Elatine are characteristic for oligo and mesotrophic lakes. This study focuses on Elatine hexandra one of the four species in Sweden. It is stated as vulnerable by the National Environment Agency and a conservation plan with guidelines to preserve the plant in Sweden is under preparation. There have been a few previous studies investigating this plant in other countries but this is the first one for Sweden. The aim of this study was to investigate the distribution, growth and reproduction of E.