Historically, approximately 25% of Sweden's wetlands have been ditched and drained in favour of agriculture, forestry, infrastructure and peat extraction. Major investments have been made in recent years to recreate the natural and environmental benefits that have been lost. Among other things, this has given rise to Falkenberg municipality's plans to apply for funding to rewet Hakamosse. The purpose of the study is to provide Falkenberg municipality with data through analysis of the current situation regarding water chemical parameters and give suggestions on sampling points and suitable parameters to monitor for Hakamosse. The study is limited to hydrology, water chemistry and greenhouse gases. The water chemistry study was performed by sampling and analysis from three sampling points on five occasions. Scientific information and knowledge gained from other rewetting projects has been collected from scientific literature, reports and semi-structured interviews. The chemical water analysis results show variations between the sampling points and the sampling occasions but with few deviating values. The control program's water chemical monitoring should build on the current situation analysis in this study. Based on the literature study, hydrological measurements should include measurements of groundwater levels and water flow. Greenhouse gas emissions can be measured with instruments or calculated using the IPCC's emission factors. A limiting factor in the implementation of monitoring programs is often the availability of time and financial resources, which often leads to a balance between sampling frequency and the number of sampling points depending on the parameter and method. The results also highlight that a risk analysis is needed as the rewetting of Hakamosse may have a major impact on the surrounding environment. / Historiskt har cirka 25% av Sveriges våtmarker dikats och torrlagts till förmån för jordbruk, skogsbruk, infrastruktur och torvtäkter. Stora satsningar har på senare år gjorts för att återskapa de natur- och miljönyttor som gått förlorade. Det har bland annat har gett upphov till Falkenberg kommuns planer på ansökan om bidrag till att återväta Hakamosse. Syftet med studien är att förse Falkenbergs kommun med underlag genom nulägesanalys av vattenkemiska parametrar samt underlag till ett kontrollprogram för Hakamosse. Kontrollprogrammet är avgränsat till hydrologi, vattenkemi och växthusgaser. Den kvantitativa vattenkemiska undersökningen utfördes genom provtagning och analys från tre provtagningspunkter under fem tillfällen. Underlag till utformning av kontrollprogram har insamlats från vetenskaplig litteratur, rapporter och semistrukturerade intervjuer. Det vattenkemiska analysresultatet visar variationer mellan provtagningspunkterna och provtagningstillfällena men med få avvikande värden. Kontrollprogrammets vattenkemiska övervakning bör bygga vidare på nulägesanalysen i denna studie. Baserat på litteraturstudien ska hydrologiska mätningar inkludera mätningar av grundvattennivåer samt vattenflöde. Växthusgasgasavgången kan förslagsvis mätas med provtagningsinstrument eller beräknas med hjälp av IPCC:s emissionsfaktorer. En begränsande faktor vid utformningen av kontrollprogram är ofta tillgången till tidsmässiga och ekonomiska resurser, vilket ofta leder till avvägning mellan provtagningsfrekvens och antalet provtagningspunkter beroende på parameter och metod. Resultatet belyser även att en riskanalys behövs då en återvätning av Hakamosse kan ha en stor påverkan på omgivningen.

The investigation of environmental impacts of 16 different contaminants originating from the E18 Highway (17 000 AADT) were carried out over the first six months of the highway‘s operational life. Investigative methods used include electrical resistivity surveying, water chemistry analyses, soil analyses, distribution modelling and transportation modelling. The investigation shows conclusively a year round infiltration due to melting of the snowpack from road salt, and a strong preferential anthropogenic pathway due to in-creased hydraulic conductivities of the road building materials relative to the natural soils. The resistivity surveys show values well below the expected values for the highway materials, indicating increased ionic content of the unsaturated zone. Time lapse resistivity modelling shows a clear downwards spreading of contamination from the roadway to subsurface distances greater than 5 m. Elevated concentrations of nearly every contaminant relative to baseline values were observed, with many concentrations of metals in the snow pack averaging values in excess of Swedish EPA groundwater limitations. Distribution modelling demonstrated a potential offset of peak values from the road surface due to ploughing and splash transport processes, but otherwise conformed to established distribution patterns. One dimensional transport modelling demonstrated the importance of adsorption and other retentive factors to the migration of contaminants to the water table, and provided an estimate for potential long term contaminant concentrations.

>Magister Scientiae - MSc / The research was driven by a need to increase the knowledge base concerning wetland ecological responses, as well as to identify and evaluate the factors driving the functioning of the Franschhoek Trust Wetland. An ecohydrological study was undertaken in which vegetation cover, depth to groundwater, water and soil chemistry were monitored at 14 sites along three transects for a 12 month period. The parameters used include temperature, pH, electrical conductivity (EC), sodium, potassium, magnesium, calcium, iron, chloride, bicarbonate, sulphate, total nitrogen, ammonia, nitrate, nitrite and phosphorus. T-tests and Principal Component Analysis (PCA) were used to analyze trends and to express the relationship between abiotic factors and vegetation. Results reflect the strong influence of hydrology, microtopography and nutrient availability in structuring vegetation composition in the wetland. The wetland has been classified as a palustrine valley bottom with channel wetland, which is predominantly groundwater-fed (phreatrotropic), but receives surface water inputs as well. Small scale gradients of microtopography allow for differences in flooding frequency and duration resulting in hydrologically distinct sites which differ chemically. Three zones were distinguished in the wetland. Hollows or low sites were characterized by intermittent flooding and drying and higher nutrient concentrations in soil and groundwater. High sites which were rarely or never flooded exhibited higher groundwater temperature and ammonia as well as iron in soils and groundwater. The inundated sites remained flooded throughout the year and were characterized by high nitrate and nitrite in soil as well as high EC, magnesium, bicarbonate, sulphate and phosphorus in groundwater. The limited availability of nitrogen in the wetland favoured plant types Typha capensis, Paspalum urvillei and Juncus .kraussii which are able to either fix nitrogen or store nitrogen during more favorable conditions. The main chemical concentration changes take place between summer and winter. The Principal Component Analyses suggest that sodium, chloride, potassium, ammonia and phosphorus are the dominant ions determining the chemistry of groundwater. Increased abstraction from the table mountain aquifer to supplement human demand may put the wetland at risk of degradation. Intensified agriculture and other land use in the area are likely to increase pollution loads into the wetland causing shifts in nutrient availability and vegetation composition. Continued and long term monitoring is essential to ensure effective management of the wetland and is highly recommended. Closer partnerships between wetland managers and scientists as well as community awareness and involvement through a volunteer monitoring programme should be encouraged

Indiana University-Purdue University Indianapolis (IUPUI) / The luting agent is a crucial factor in the outcome of cemented fixed restorations. A new water-based cement, Ceramir C&B (CM), approved to be marketed in the US, is composed of calcium aluminate and glass ionomer. CM is a luting agent indicated for permanent cementation of cast restorations, all-zirconia or all-alumina crowns, and prefabricated metal and cast dowel and cores. The manufacturer claims that the cement has demonstrated favorable biocompatibility properties when tested in vitro and in vivo and has proven to be bioactive. The objective of this study was to evaluate volumetric dimensional changes and the amount of Ca2+ released by the new luting agent. Twenty specimens of each material, namely calcium aluminate glass ionomer, resin-modified glass ionomer, and two resin luting agents, were fabricated and weighed. The 20 specimens for all materials were divided into four groups (five samples in each group) based on storage conditions: silicone oil at 22°C and 37°C and distilled water at 22°C and 37°C. Using the manufacturers’ instructions for each material, cylindrical specimens were prepared with dimensions of 7 +0.1 mm in diameter and 2 +0.1 mm in height. A 0.01-mg resolution balance was used to determine volumetric dimensional change using an Archimedean equation. Measurements were made 30 minutes after mixing, and at the time intervals of 7 days, 14 days, 21 days, and 30 days, and after total dehydration of the specimen. Chemical analyses of the solutions were performed using atomic absorption spectroscopy to determine the Ca+2 ion concentration. Moreover, the pH values were measured to determine the OH–concentration in the solutions. The results showed that CM had the most expansion among the tested luting agents in distilled water at 22°C and 37°C, and significantly increased at higher temperature. In silicone oil, resin-modified glass ionomer shrank the most and also shrank more with the high temperature. The result of the ion concentration analysis indicated that Ca+2 and OHion release increased with increasing time and also significantly with temperature rise. In conclusion, calcium aluminate-glass ionomer exhibited the most significant dimensional change when stored in water storage. The solubility of the tested luting agents should be evaluated in the future because they were not evaluated in this study. Furthermore, to evaluate the clinical effect of the dimensional changes, the impact on the gap formation at tooth-crown margins should be determined in future work.

No description available.

No description available.

No description available.

No description available.

No description available.

No description available.