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Antarctic mass balance is mainly controlled by surface mass balance (SMB, i.e. the net effect of precipitations at the surface of the ice sheet) and ice discharge at its margins, mostly through ice shelves. These floating ice bodies made from ice flowing from the continent to the ocean are buttressed by ice rises (elevation of the sea floor on which ice shelf re-grounds) such as the Derwael Ice Rise (DIR) in Dronning Maud Land (DML). In addition to this role important to consider in the future contribution of Antarctica to sea level rise, ice rises are also “climate dipsticks” helping to reconstruct the climate of the past centuries to millennia at high resolution. Due to their coastal location, they witness the changes happening there more rapidly than inland. Furthermore, their internal stratigraphy forms arches that allow to assess their stability, to date their own formation and therefore, in some cases, to constrain the past extension of the ice sheet at the scale of several millennia. As part of the IceCon project :Constraining ice mass changes in Antarctica, this thesis aimed to drill a 120 m ice core (named IC12 for the IceCon project, 2012) at the divide of the DIR and perform physico-chemical analyses to study its density and its internal annual layering with the aim of reconstructing SMB of the last two centuries. We also recorded a virtual image of the borehole using an optical televiewer (OPTV) to assess the ability of this instrument to reconstruct a density profile and measure vertical strain rates when the logging is repeated in the same borehole after a sufficient period of time (here, 2 years).The results show a general increase in snow accumulation rates (SMB) of 30-40% during the 20th century, particularly marked during the last 20-50 years. SMB variability is governed to a large extent by atmospheric circulation and to a lesser extent by variations in sea ice cover. The vertical velocity profile measured from repeat borehole OPTV was applied to refine SMB correction and the results fall in the error range of the corrections made using a model previously developed to study the DIR’s stability. This thesis also contributed to characterizing the spatial variability of SMB across the DIR by dating internal reflection horizons (IRHs), former surfaces of the DIR buried under subsequent snow layers and detected using radio-echo-sounding, and by measuring the density profile of IC12. SMB is found to be 2.5 times higher on the upwind slope than on the downwind slope due to the orographic effect. This pattern is regularly observed on ice rises in DML and stresses the importance of adopting a sufficient spatial resolution (5 km) in climate models.Finally, the technical developments allowing to rapidly reconstruct a density profile from the OPTV image of a borehole contributed to improving our knowledge of two features of Antarctic ice shelves, namely melt ponds, influencing surface mass balance and subglacial channels, influencing basal mass balance. Specifically, the results show that density is 5 % higher in surface trenches associated with subglacial channels, and that ice below melt ponds can reach the density of bubble-free ice due to melting and refreezing processes, with implications on ice shelf viscosity. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished

Perfluoroalkyl acids (PFAAs) are man-made chemicals. Their unique properties make them beneficial for a wide range of industrial and consumer applications, such as constituents in fire fighting foams, hydraulic oils and food packaging materials.PFAAs have shown to be highly persistent in the environment, and the toxicological potential of long chain PFAA homologues is of a concern. International regulation and voluntary actions by the industry have been implemented and led to reduced primary emissions of PFAAs to the environment. However, the concentrations of some PFAAs in e.g. birds from the Baltic Sea are still very high and of ecotoxicological concern. Measures to reduce the PFAA contamination require an understanding of the sources and how the PFAAs are being transported in the environment.In this licentiate thesis a mass balance was assembled for perfluorohexanoic acid (PFHxA), perfluorooctanoic acid (PFOA), perfluorodecanoic acid (PFDA) and perfluorooctane sulfonic acid (PFOS) in the Baltic Sea. A one-box model was used including the input pathways river inflow, atmospheric deposition, wastewater discharges and inflow from the North Sea via the Danish Straits, while the loss processes considered were sediment burial, transformation of the chemicals and outflow to the North Sea via the Danish Straits. Additionally, the inventories of the four target PFAAs in the Baltic Sea were estimated. Both chemical fluxes and inventories were estimated using recently published monitoring data (2005-2010).In order to obtain a detailed perspective on the current knowledge regarding PFAAs in the Baltic Sea, challenges and uncertainties in data selection were discussed for the most dominant input pathways. This included WWTP emissions and calculation of emission factors (EFs), atmospheric deposition and riverine inflow.River inflow and atmospheric deposition were the dominant inputs, while wastewater treatment plant (WWTP) effluents made a minor contribution. The input to the Baltic Sea exceeded the output for all 4 PFAAs, suggesting that inputs were higher during 2005-2010 than during the previous 20 years despite efforts to reduce emissions of PFAAs. Comparing the difference between PFAA input and output with the PFAA inventory, the doubling time for the concentration in the Baltic Sea was estimated to be 8-94 yr for PFHxA, 12-16 yr for PFOA, 3-5 yr for PFDA and 4 yr for PFOS. The surplus of the input can be an effect of retention and delayed release of PFAAs from atmospheric deposition in the soils and groundwater of the watershed.The licentiate thesis contributes to a holistic understanding of the major input and output pathways and inventories of PFAAs in the Baltic Sea. Furthermore, it points out current knowledge gaps in our understanding of sources and fate of PFAAs in the aquatic environment. / <p>At the time of the defence the following papers were unpublished and had a status as follows: Paper 1: Manuscript</p>

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22427号 / 工博第4688号 / 新制||工||1732(附属図書館) / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 高岡 昌輝, 教授 酒井 伸一, 准教授 大下 和徹 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

Stormwater runoff may contain high levels of pollutants and is regulated by the Federal National Pollution Discharge Elimination System (NPDES). Stormwater bioretention (BR) systems are often used to satisfy these regulations. BR systems collect accumulated runoff that leaches into groundwater. A greenhouse study evaluated nutrient and metal removal among plant species that are typically found growing in BR systems. A field demonstration study assessed citric acid enhanced metal bioaccumulation potential under typical BR system conditions. The greenhouse experiment examined pollutant retention, and bioaccumulation potential for six plant species undergoing three hydraulic and pollutant loads. Results verified there was 98% recovery of total phosphorous over the study period. Biomass increased with higher hydraulic and pollutant loads for all species. Phragmites australis, Carex praegracilis, and Carex microptera took up significantly more total phosphorous and nitrogen mass into shoots than Typha latifolia, Scirpus valid us, and Scirpus acutus. This study also found that 89% of applied metals were removed within the top 27 em of soil in all treatments. Similar results were found regarding copper, lead, and zinc concentrations and bioaccumulation. Carex praegracilis, and Carex microptera exhibited higher metal distribution in plant tissue and exfiltrate, and lower distribution in the soil media than the other species. This indicated species differences in biological and chemical processes taking place within the simulated BRsystems. The field experiment investigated citric acid enhanced metal bioaccumulation potential among three different plant species under representative BR conditions. Citric acid significantly increased metal concentrations in the soil pore water for the planted treatments, but this did not result in increased metal uptake into plant tissue. However, notable differences were found among species, where Carex microptera accumulated more AI, Cr, Cu, and Fe in the above ground tissue than Helianthus maximiliani and Typha /atifolia (except for Cu in Helianthus). These results provide greater insight into the biological and chemical process that affect transport, uptake and translocation of nutrients and metals, and confirm the importance of species selection in BR systems to optimize nutrient and metal retention and recovery from stormwater runoff to minimize subsequent groundwater pollutant loading.

Introduction (and purpose): At every construction project there is a lot of soil moved around and managed. Mass management is an important topic which affect every project. Mass balance is what is tried to achieve. If mass balance is achieved no masses is bought or transferred from the project. If a project has deficit mass, they need to buy soil from outside of the project and move it with trucks. These transports are usually quite long which means it gets cost inefficient. It also has a negative impact on the climate. If there is excess mass within the project soil needs to be removed with trucks. Municipality sees on contaminated soil in different ways depending on where in Sweden it is placed. This can also affect the length on transports of soil.The purpose of the report is to find a solution of how construction company can do mass management together to find mass balance from a bigger perspective instead of the specific project. Method: The study will be of a qualitative character and been executed with semi- structured interviews and literature search to answer the studies questions. The interviews have been implemented with land contractors in Jönköping. Results and analysis: The study shows that there is some lack in the regulation regarding secondary masses. All municipalities have their own regulation which means that there are different problems depending on where you are located. It takes a long process to reuse masses today which not is economically favorable. The study highlight deficiency that exists today and show suggestions for a more effective mass management. Study shows also that there is an interest for a collective platform where you can buy and sell secondary masses. In that way companies and municipalities can cooperate for a mutual mass management by buying and selling masses from each other. Discussion: Through interviews with contractors in the industry the questioning has been confirmed. The result is based on solution and suggestions which can promote a circular mass management. To answer the questions the study is based on different impression, opinions and aspects.

Use of pervious concrete pavement as a method of stormwater management has shown great promise in previous studies. Reduction in runoff, water quality improvements, and long-term economic benefits are but a few of its many advantages. Regulatory agencies such as the St. Johns River Water Management District require further research into the performance of pervious concrete pavement before granting credits for its use as a best management practice in controlling stormwater. As a part of a larger series of studies by UCF's Stormwater Management Academy, this thesis studies the hydrologic mass balance of pervious concrete pavement in sandy soil common in Florida. In order to conduct this study, a field experiment was constructed at the UCF Stormwater Field Lab. The experiment consisted of three 4-foot tall cylindrical polyethylene tanks with 30-inch diameters. All three tanks were placed into the side of a small embankment and fitted with outlet piping and piezometers. The test tanks were assembled by laying a 6-inch layer of gravel into the bottom of each tank, followed by a layer of Mirafi geofabric, followed by several feet of fine sand into which soil moisture probes were laid at varying depths. Two of the tanks were surfaced with 6-inch layers of portland cement pervious concrete, while the third tank was left with a bare sand surface. Mass balance was calculated by measuring moisture influx and storage in the soil mass. Data collection was divided into three phases. The first phase ran from August to November 2005. Moisture input consisted of normal outdoor rainfall that was measured by a nearby rain gauge, and storage was calculated by dividing the soil mass into zones governed by soil moisture probes. The second phase ran for two weeks in March 2006. Moisture input consisted of water manually poured onto the top of each tank in controlled volumes, and storage was calculated by using probe readings to create regression trendlines for soil moisture profiles. The third phase followed the procedure identical to the second phase and was conducted in the middle of April 2006. Data tabulation in this study faced several challenges, such as nonfunctional periods of time or complete malfunction of essential measuring equipment, flaws in the method of calculating storage in phase one of the experiment, and want of more data points to construct regression trendlines for soil moisture calculation in phases two and three of the experiment. However, the data in all phases of the experiment show that evaporation volume of the tanks with pervious concrete surfacing was nearly twice that of the tank with no concrete. Subsequent infiltration experiments showed that pervious concrete pavement is capable of retaining a portion of precipitation volume, reducing infiltration into the underlying soil and increasing total evaporation in the system.

Portland Cement pervious concrete's ability to permit water infiltration has encouraged its use as a stormwater management tool. However, the material has suffered historically poor support due to a number of factors, including failures due to poor mix design and improper construction techniques, concern about lesser structural strength, concern about poor long term performance due to clogging of surface pores and undefined credit for stormwater management. This study focuses on long term performances of pervious concrete parking lots and their stormwater management credit. Before stormwater management credit could be estimated, it was necessary to develop a testing device to gather information from existing pervious concrete parking lots currently in use. Eight parking lots were examined to determine the infiltration rates of the pervious concrete, as well as to verify the soil makeup beneath pavement. A total of 30 cores were extracted from pervious concrete parking lots and evaluated for infiltration rates. Three of the sites had a pervious concrete section that included a gravel reservoir. Infiltration rates were measured using the application of an embedded single-ring infiltrometer. In an attempt to provide an estimate of credit, a mass balance model was created to be used for simulation of the hydrologic and hydraulic function of pervious concrete sections. The purpose of the model is to predict runoff and recharge volumes for different rainfall conditions and hydraulic properties of the concrete and the soil. The field derived hydraulic data were used to simulate infiltration volumes and rainfall excess given a year of rainfall as used in a mass balance operated within a spreadsheet. The results can be used for assessing stormwater management credit.

Although most processes governing the surface mass balance on mountain glaciers are well understood, the causes and extent of spatial variability in accumulation remain poorly constrained. In the present study, the EBFM distributed mass balance model is newly coupled to terrain based modelling routines estimating mass redistribution by snowdrift, preferential deposition, and avalanching (ST-EBFM) in order to model winter balance on Storglaciären, Sweden. STEBFM improves the spatial accuracy of winter balance simulations and proves to be a versatile and computationally inexpensive model. Accumulation on Storglaciären is primarily driven by direct precipitation, which seems locally increased due to small scale orographic effects. Wind driven snow transport leads to significant deposition in the accumulation zone and slight erosion in the ablation zone. The pattern is generally consistent from year to year. Avalanching is the smallest contributor to winter balance, but cannot be neglected. The physical complexity of avalanches and high year to year variability render simulations of the process somewhat uncertain, but observations seem to confirm the large impact that the process can have on the glacier at very localised scales. The role of mass transporting processes in maintaining the current mass equilibrium on Storglaciären highlights the necessity to understand the links between climatic predictors and accumulation in order to accurately assess climate sensitivity.

Human exposure to per- and poly-fluoroalkyl substances (PFAS) occurs mainly through two pathways, inhalation and ingestion. Dietary exposure to persistent organic pollutants (POPs), including PFAS, is driven mainly by the consumption of foods of marine or terrestrial animal origin. Therefore, the intake of fish from waters in populated or polluted areas may be a source of human exposure to PFAS. The overall aim of the study was to estimate human exposure to PFAS through the consumption of fish caught in Swedish waters. Analyses of extractable organofluorine (EOF) were performed to serve as an important metric alongside target analysis to better understand the total amount of PFAS in the human sera and fish samples. The serum samples represent individuals who have lived at some point about 5 km from the glass industry in Nybro and Emmaboda. For this study with the Glasbruket study population, the highest concentrations were found for PFOS followed by PFOA, PFNA and PFHxS (medians of 7.9, 1.9, 1.4 and 0.8 ng/mL). Also, the difference in this population between men/women and high/low fish consumers were also addressed. It was stated that there was a statistically significant difference in average Σ17 PFAS concentration between the male and female groups (p &lt; 0.05, two-tailed test). However, the differences between the low and high consumer groups were not statistically significant even though the PFAS levels were higher in the high consumer group. The organofluorine mass balance analysis revealed that 80.1% (ranged from 68.3−93.7%) of the EOF in female samples could not be explained, whereas 57.3% (ranged from 0−99.4%) for the male group was of unidentified origin. Two methods were evaluated for PFAS and EOF analysis of fish muscle, namely, acetonitrile extraction and ion-pair extraction. The selected method, the ion-pair extraction, was performed on fish muscle samples. The fish species included perch (Perca fluviatilis), northern pike (Esox Lucius) and zander (Sander lucioperca) that were collected from seven different lakes in the vicinity of Nyro and Emmaboda. The sum of targeted PFAS (∑14PFAS) across all fish samples analysed ranged from 0.9 to 6.2 ng/g. Mostly, perfluoroalkyl carboxylic acids (PFCAs), precursors to PFCAs and novel PFAS were found in the fish samples. A large part of the EOF content cannot be identified with the targeted PFAS compounds. The average identified EOF fraction for all fish was 2.3% (ranging from 0.8 to 7.2%). For this study, 10 PFAS were found in both sera and fish samples. Therefore, freshwater fish consumption can be identified as one of the contributors to the PFAS concentrations in the Glasbruket population. The fish samples contained precursor compounds as well, that were not found in human serum. These precursor compounds can contribute to the concentrations of PFAAs in serum through biotransformation in the human body to perfluoroalkyl acids (PFAAs). Due to the widespread use of PFAS and their persistence in the environment, it is difficult to determine the relationship between the levels found in serum and fish. The Glasbruket population could be exposed to other sources besides fish.