<p>Bornsjön är Stockholms viktigaste reservvattentäkt och kan tillgodose staden med dricksvatten i flera månader om Mälaren skulle slås ut. Det är därför viktigt att Bornsjön håller en god vattenkvalitet. Under de senaste åren har vattenkvaliteten avseende totalfosfor i Bornsjön försämrats. Hög belastning av fosfor kan leda till övergödning i en sjö. När en sjö är övergödd uppstår ökad syreförbrukning som kan leda till syrebrist. Vid syrebrist frigörs fosfor från sediment och det blir större näringstillgång som bidrar till mer övergödning. Övergödning beror ofta på utsläpp från punktkällor, till exempel från avloppsvattenutsläpp, men kan även bero på diffusa utsläpp från jordbruksmark och skog inom avrinningsområdet.</p><p>Syftet med examensarbetet var att förstå vilka fosforprocesser som är viktiga för Bornsjönsom ekosystem och med den dynamiska massbalansmodellen LakeMab utvärdera olika realistiska åtgärder för att minska belastningen av totalfosfor. Marken runt Bornsjön ägs av Stockholm Vatten och med resultaten från detta arbete ska Stockholm Vatten få olika förslag på vilka åtgärder som bör prioriteras. Resultat från andra kända modeller har även jämförts med LakeMabs resultat.</p><p>Studien visade att det är möjligt att reglera belastningen av totalfosfor på Bornsjön genom till exempel införande av vallodling, minskning av åkerareal och genom minskade utsläpp från enskilda avlopp. Dessa olika åtgärder kan kombineras för ökad effekt. Det är även möjligt att sänka totalfosforkoncentrationen i sjön genom att sänka sjöns pH-värde. Detta är dock en åtgärd som inte rekommenderas på grund av att en förändring av det naturliga pH-värdet påverkar ekosystemet.</p><p>För att i framtiden kunna göra liknande studier med mer tillförlitliga resultat bör provtagningsprogrammet i dikena utökas, speciellt vid kraftig nederbörd då fosforläckaget från marken är större.</p> / <p>Lake Bornsjön is Stockholm’s most important reserve water source and can supply the city with drinking water for several months in case Mälaren would be polluted. Thus it is important to maintain the water quality of Bornsjön. In the last years the quality of the drinking water has in reference to total phosphorus in Bornsjön degraded. High load of phosphorus leads to eutrophication in lakes. When a lake is eutrophicated the respiration increases, which may lead to a lack of oxygen in the water. At reduced conditions of oxygen, phosphorus will be released from the sediments which lead to an increased eutrophication. Eutrophication is often the result of anthropogenic point sources, for example waste water treatment plants, but can also be due to diffuse sources like agricultural and forests within the catchment area.</p><p>The purpose with this Master degree project was to understand which phosphorus processesare important for Bornsjön as an ecosystem and with the dynamic mass balance model LakeMab evaluate different realistic actions to decrease the load of total phosphorus. Most of the catchment area around Bornsjön is owned by Stockholm Vatten and the aim of this project is to recommend Stockholm Vatten which actions should be prioritized. Also, results from other models have been compared with the results from LakeMab.</p><p>This study showed that it is possible to regulate the load of total phosphorus to Bornsjön, for example with ley farming, less agricultural area and decreased load from individual sewage systems. These different actions can be combined for an increased effect. It is even possible to lower the concentration of the total phosphorus in the lake by decreasing its pH-value. However, this action is not recommended because a change of the natural pH will affect the ecosystem.</p><p>To make similar studies in the future with more reliable results it is important to extend the sample scheme for the ditches, especially at occasions with high precipitation which leads to increased phosphorus leakage from the soil.</p>

<p>This thesis contributes to the understanding of glacier response to climate change by ice dynamical studies on Storglaciären, Sweden, and Bonnevie-Svendsenbreen, Kibergbreen and Plogbreen in Dronning Maud Land, Antarctica. Ice surface velocities, ice geometry and temperature information is fed through a force budget model to calculate ice mass outflux of these glacial systems via three-dimensional stress distributions for a flux-gate. </p><p>Field data were collected through repeated DGPS and GPR observations on Storglaciären between July 2000 to September 2001 and on Kibergbreen and Plobreen during the SWEDARP 2002/03 expedition to Antarctica. The work was strongly supported by remotely-sensed information.</p><p>The results from Storglaciären show a strength in the force budget model to discern both spatial and temporal variability in ice dynamical patterns. It highlights the influence of seasonality and bedrock topography upon glacier flow. A modeling experiment on Bonnevie-Svendsenbreen suggested that ice temperature increases substantially under conditions of high stress (≥0.4 MPa) due to strain-heating. This provides a positive feedback loop, increasing ice deformation, as long as it overcomes the advection of cool ice from the surface. These results explain, to some extent, the mechanism behind fast flowing ice streams. Mass flux caclulations from Bonnevie-Svendsenbreen suggest that the outflux given from force budget calculations can be used as a gauge for influx assuming steady state conditions. Plogbreen receives an influx of 0.48±0.1 km³ a^-1 and expedites a discharge volume of 0.55±0.05 km³ a^-1. This indicative negative mass balance is explained by a falling trend in upstream accumulation and the recent rise in global sea level, as it is likely to induce glacier acceleration due to a reduction in resistive forces at the site of the gate. This result is comparable with other Antarctic studies reporting negative mass balances, e.g. from WAIS, as caused by changes in the global atmospheric circulation pattern.</p>

This thesis contributes to the understanding of glacier response to climate change by ice dynamical studies on Storglaciären, Sweden, and Bonnevie-Svendsenbreen, Kibergbreen and Plogbreen in Dronning Maud Land, Antarctica. Ice surface velocities, ice geometry and temperature information is fed through a force budget model to calculate ice mass outflux of these glacial systems via three-dimensional stress distributions for a flux-gate. Field data were collected through repeated DGPS and GPR observations on Storglaciären between July 2000 to September 2001 and on Kibergbreen and Plobreen during the SWEDARP 2002/03 expedition to Antarctica. The work was strongly supported by remotely-sensed information. The results from Storglaciären show a strength in the force budget model to discern both spatial and temporal variability in ice dynamical patterns. It highlights the influence of seasonality and bedrock topography upon glacier flow. A modeling experiment on Bonnevie-Svendsenbreen suggested that ice temperature increases substantially under conditions of high stress (≥0.4 MPa) due to strain-heating. This provides a positive feedback loop, increasing ice deformation, as long as it overcomes the advection of cool ice from the surface. These results explain, to some extent, the mechanism behind fast flowing ice streams. Mass flux caclulations from Bonnevie-Svendsenbreen suggest that the outflux given from force budget calculations can be used as a gauge for influx assuming steady state conditions. Plogbreen receives an influx of 0.48±0.1 km3 a-1 and expedites a discharge volume of 0.55±0.05 km3 a-1. This indicative negative mass balance is explained by a falling trend in upstream accumulation and the recent rise in global sea level, as it is likely to induce glacier acceleration due to a reduction in resistive forces at the site of the gate. This result is comparable with other Antarctic studies reporting negative mass balances, e.g. from WAIS, as caused by changes in the global atmospheric circulation pattern.

The environmental occurrence and behaviour of the brominated flame retardant (BFR) decabromodiphenyl ethane (dbdpe) has only been studied to a limited extent. It is structurally similar to decabromodiphenyl ether (decaBDE), which makes it conceivable that dbdpe may also become an environmental contaminant of concern. A method for environmental analysis and comparative assessments of dbdpe and decaBDE was developed. Both BFRs were studied in: a mass balance of the Henriksdal WWTP in Stockholm (Paper I); an international survey of sewage sludge (Paper II); sediment along a transect from Henriksdal WWTP to the outer archipelago of Stockholm and from isolated Swedish lakes (Paper III); and a benthic food web from the Scheldt estuary (Paper IV). Dbdpe was found in sludge from every country surveyed, indicating that it may be a worldwide concern. The WWTP mass balance showed that virtually all of the BFRs were transferred from wastewater to sludge. A small fraction was emitted via the effluent, confirming emissions to the aquatic environment. In the marine sediment, the BFR levels close to the WWTP outfall were high. They decreased along the transect to low levels in the outer archipelago. The study of lake sediment showed a widespread presence of dbdpe in the Swedish environment and provided evidence that it originates from long range atmospheric transport. In the food web, dbdpe did bioaccumulate to a small extent which was similar to decaBDE. The transfer of the BFRs from sediment to benthic invertebrates was low, while transfer from prey to predator was higher. Biodilution was observed rather than biomagnification. This work suggests that the persistence, the susceptibility to long range atmospheric transport, and the potential for bioaccumulation are similar for dbdpe and the regulated decaBDE that it is replacing. Thus, there is a risk that a problematic environmental pollutant is being replaced with a chemical that is equally problematic. / At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Submitted. Paper 4: Manuscript.

Massive sulfide deposits in the Noranda mining camp, northwestern Québec, are mainly associated with extensive footwall alteration defined by intense chloritization and sericitization. However, Fe-carbonate alteration also occurs in proximity to some deposits. To test the exploration significance of carbonate alteration in the camp, two areas of intense carbonate alteration were examined, around the small Delbridge deposit and near the new Pinkos occurrence in the Cyprus Rhyolite. Between 1969 and 1971, the Delbridge deposit produced 370,000 t of ore grading 9.6% Zn, 0.61% Cu, 110 g/t Ag, and 2.1 g/t Au. Recent drilling at the new Pinkos occurrence intersected 2.64 m of massive to semi-massive sulfides grading 8.1% Zn and 18.2 g/t Ag. Alteration mapping has shown that the distribution of Fe-carbonates can be used to identify vertically extensive zones of hydrothermal upflow at both properties. At Delbridge, intense Fe-carbonate alteration in brecciated rhyolite defines a pipe-like upflow zone that extends vertically for up to 300 m within the stratigraphic footwall of the massive sulfides and 100 m into the hanging wall. The location of known massive sulfide mineralization coincides with the intersection of the alteration pipe and a favorable horizon marked by the occurrence of fine-grained volcaniclastic rocks. At Pinkos, a similar zone of Fe-carbonate alteration occurs in outcrops of coherent rhyolite. Fe-carbonate alteration is most intensely developed along polygonal cooling fractures in massive rhyolite and decreases in intensity towards the centers of the columns. Fe-carbonate stringers and locally abundant matrix carbonate occur in fragmental rocks at the stratigraphic top of the coherent rhyolite flows and are most intense at the location of sulfide-bearing outcrops that mark the known mineralized horizon. Whereas Fe-carbonate alteration defines the central part of the hydrothermal upflow zones at both properties, disseminated pyrite occurs at the margins and is widespread outside the main upflow zones. This may indicate that Fe-carbonate in the main upflow zones formed at the expense of earlier disseminated sulfides. Replacement of pyrite by synvolcanic Fe-carbonate alteration at Delbridge and Pinkos can probably be attributed to a relatively high concentration of dissolved CO2, possibly of magmatic origin, in the main-stage ore-forming fluids.

Aus Beobachtungsdaten der Satellitenmission GRACE (Gravity Recovery and Climate Experiment) können Variationen des Erdschwerefeldes auf großen räumlichen Skalen mit hoher Genauigkeit abgeleitet werden. Die Variationen auf zeitlichen Skalen von mehreren Tagen bis Wochen und räumlichen Skalen von wenigen hundert Kilometern sind insbesondere auf Änderungen der kontinentalen Wassermassen zurückzuführen. Die vorliegende Promotionsarbeit beschäftigt sich mit der Bestimmung hydrologischer Massenvariationen aus GRACE-Daten am Beispiel der vier größten sibirischen Flusseinzugsgebiete Ob, Jenissei, Lena und Kolyma. Darauf aufbauend sollen in Kombination mit atmosphärischen Daten der NCEP-Reanalyse Süßwassereinträge in den Arktischen Ozean abgeleitet werden. Die Süßwassereinträge beeinflussen nachhaltig den Salzgehalt und damit das ozeanographische Regime des Arktischen Ozeans, welcher wiederum einen Einfluss auf die globale thermohaline Zirkulation hat. Da die großen Strömungen des Weltozeans einen grundlegenden Faktor des globalen Klimageschehens darstellen, sind die Änderungen des Süßwassereintrages ein wichtiger Aspekt hinsichtlich prognostizierter Klimatrends. Der Abfluss kann an ausgewählten Messpunkten mit einer hohen zeitlichen Auflösung beobachtet werden. Die Datenreihen weisen jedoch immer wieder Lücken auf und die bodengebundenen Messungen sind oft schwierig und kostenintensiv. Messmethoden, die unabhängig vom Zugang ins Messgebiet sind, können einen großen Fortschritt bei der Beobachtung sich ändernder Massen und Süßwasserflüsse leisten und damit einen Beitrag für ein besseres Verständnis gekoppelter komplexer Prozesse der Arktis liefern. Da die Fehlerstruktur der GRACE-Daten komplex und bis heute nicht vollständig verstanden ist, erfolgt zunächst eine Untersuchung des GRACE-Fehlerhaushaltes. Zudem werden die Fehlereffekte aufgrund des begrenzten räumlichen Spektrums und damit einhergehender Leck-Effekte auf Ebene von Gebietsmittelwerten analysiert und Lösungsvorschläge diskutiert. Dabei sind folgende Aspekte von Bedeutung: Erweiterung der GRACE-Datenreihe um geeigente Terme ersten Grades und Abschätzung von Leck-Effekten, verursacht durch das begrenzte Spektrum der Kugelfunktionsentwicklung. Leck-Effekte aufgrund ozeanischer Signalanteile sind bzgl. der Einzugsgebiete sibirischer Flusssysteme klein (< 1%), wohingegen Leck-Effekte aufgrund kontinentaler Signalanteile je nach Gebietsgröße relative Fehler von 8-17% nach sich ziehen. Die größten Fehlereffekte resultieren jedoch aus den Koeffizienten hoher Grade. Die Filterung der GRACE-Daten ermöglicht die Glättung fehlerbehafterer Signalanteile. Neben den in der Literatur gängigen Filtern wurde im Rahmen der Arbeit ein Kombinationsfilter entwickelt, welches auf Basis von räumlichen Vorinformationen aus Hydrologiemodellen signifikante Signalstrukturen in den GRACE-Datenreihen detektiert. Somit muss lediglich ein Restsignal mittels Filterung gedämpft werden. Mit dem Kombinationsfilter können sowohl feinere Signalstrukturen als auch größere Signalamplituden auf Land erhalten werden. Im Vergleich zu reinen Filteranwendungen werden hier Gesamtsignalstärke, Amplitude und Phase des jährlichen Signals gut repräsentiert. Darauf aufbauend lassen sich, in Kombination mit atmosphärischen Daten, Abflüsse für die sibirischen Flusssysteme aus GRACE-Wasserspeichervariationen ableiten. Die Validierung der berechneten Abflüsse anhand beobachteter Abflüsse zeigt eine hohe Übereinstimmung von bis zu 83%. Eine Gegenüberstellung des berechneten Abflusses der Lena mit Wasserstandsmessungen im Mündungsbereich zeigt zudem einen Zusammenhang zwischen dem maximalen Abfluss im Frühjahr und einer Zunahme des Wasserstandes in der Laptewsee. / The satellite mission GRACE (Gravity Recovery and Climate Experiment) observes the earth's gravity field on temporal scales of a few days to several weeks and spatial scales of a few hundred kilometers with high accuracy. A large part of the variations of the gravity field originate from hydrological mass changes on the continents. The dissertation discusses the determination of hydrological mass variations from GRACE for the Siberian water systems of the rivers Ob, Yenisey, Lena and Kolyma. The mass variations from GRACE data are combined with atmospheric data of the NCEP reanalysis to calculate the freshwater fluxes in the Arctic Ocean. The freshwater fluxes strongly influences the salinity and the oceanographic regime of the Arctic Ocean. In turn, the Arctic Ocean controls the global thermohaline circulation which is very important for the global climate. Because these large currents of the ocean influence the global climate, the changes of the freshwater fluxes in the Arctic Ocean are an important factor for the global climate change. The runoff can be measured pointwise with high temporal resolution, but measurements in the high latitudes are difficulty and expensive. Independent methods to measure the mass changes in the Arctic can help to determine the freshwater fluxes on large spatial scales, and contribute to understand the coupled and complex processes of the Arctic. Until present, the complex error structure of the GRACE data are not fully understand. The dissertation examines the errors and analysizes the leakage caused by the limited spectrum of the Stokes coefficients. A proposal for a solution will be discussed. The following steps are important: Expanding the GRACE data with adequate terms of degree one; Valuation of leakage errors because of the limited spectrum. Leakage due to oceanographic signals of the Arctic Ocean are small (< 1%). Leakage errors due to signals on land produces relative errors of basin averages of 8-17%. Beyond that, the largest errors are caused by the coefficients of higher degree. Filtering is an effective method to damp the error signals. In addition to the common filters described in the literature, a filter method, called composite filter, was created. Significant structures from hydrological models can be deteceted in the GRACE data without any other filtering. Only the residual signals should be filtered by using one of the common filters. In comparison to the common filters, the composite filter represents the signal strength, the signal structures, the amplitude and the phase of the saisonal signal on the continents much better. Combining hydrological mass variations from GRACE data with atmospheric data (for example the NCEP reanalysis) the runoff of the four Siberian river systems can be calculated. The validation of the calculated runoff using observations leads to a good agreement (83% for Yenisey and Lena). Furthermore, it is possible to combine the runoff of a river system with measurements of water level and salinity in the Arctic Ocean. The high runoff of the Lena river system in spring is visible in the water level changes in the Laptev sea.

Mit der Mission des Ice, Cloud and Land Elevation Satellite (ICESat) gelangte erstmals ein Laseraltimetersystem in einen erdgebundenen Orbit. Die vorliegende Arbeit verdeutlicht anhand von drei verschiedenen Anwendungen das Potenzial dieser Altimeterdaten zur Überwachung des Antarktischen und des Grönländischen Eisschilds. Beide Schilde bilden ein Schlüsselglied im globalen Klimasystem der Erde. In einem ersten Hauptabschnitt werden die ICESat-Altimeterdaten für das Gebiet des Lake Vostok, des größten Vertreters subglazialer Seen in der Antarktis, untersucht. Dieses Gebiet eignet sich durch die Höhenstabilität des über dem See liegenden Eisschilds insbesondere als Validierungsgebiet für Altimeterdaten. Diese werden hinsichtlich der zwischen den Lasern auftretenden Offsets umfassend analysiert. Die ermittelten Offsets variieren in einem Bereich zwischen -7.5 und +13.9 cm und erreichen damit die angestrebte Messgenauigkeit der Mission. Im Hinblick auf eine Bestimmung von zeitlich linearen Höhenänderungen der Eisschilde stellen sie den größten genauigkeits-limitierenden Faktor dar. Aus den um die Offsets korrigierten Altimeterdaten wird ein rasterförmiges Topographiemodell der Eisoberfläche erstellt. Dieses wird umfassend untersucht. Im Anschluss werden glaziologische Anwendungen vorgestellt, für welche das Topographiemodell eine zentrale Grundlage bildet. Unter anderem erfolgt in der Kombination mit Eisdicken- und Geoidinformationen der Nachweis, dass sich das Eis über dem See im hydrostatischen Gleichgewicht befindet. Im Zuge dieser Untersuchung wird aber auch deutlich, dass an einigen Stellen des Sees das Gleichgewicht verletzt wird. Mögliche Ursachen hierfür werden näher untersucht und eingehend diskutiert. Für den Grönländischen Eisschild erfolgt die Analyse der um die Laseroffsets korrigierten Altimeterdaten zur Ableitung zeitlich linearer Höhenänderungen. Die methodische Basis hierfür bildet eine Wiederholspuranalyse der Altimeterdaten. Zur Minimierung des Einflusses der lokalen Topographie und zur besseren Separation der saisonalen Höhenvariation werden die korrespondierenden Altimetermessungen entlang der Referenzspuren an ein drei-komponentiges mathematisches Modell durch Ausgleichung bestmöglich angepasst. Die für den ICESat-Missionszeitraum bestimmte mittlere Höhenrate des Eisschilds beträgt -13.0±0.5 cm/a. Die stärkste Höhenabnahme verzeichnet der Eisschild in den westlichen und südöstlichen küstennahen Randbereichen. Unter Verwendung der Eisdichte für die Volumen-Massen-Umrechnung entspricht dies einer Massenänderung von -209.5±35.6 Gt/a. Dies entspricht einem eustatischen Meeresspiegelanstieg von +0.6±0.1 mm/a. In einer dritten Anwendung werden die ICESat-Altimeterdaten über dem Amery-Schelfeises untersucht. Es wird eine Methodik vorgestellt, welche auf der Kreuzkorrelation von Höhenprofilen verschiedener Epochen beruht und zur Ableitung von Fließgeschwindigkeiten des Schelfeises dient. Der entwickelte Ansatz wird auf die ICESat-Referenzspur 49 angewendet. Sie verläuft entlang der zentralen Achse des Schelfeises. Im Bereich zwischen -71.6° und -70.1° Breite wächst die Fließgeschwindigkeit von +0.83±0.09 m/d auf +1.02±0.06 m/d an. Das Ergebnis steht im Einklang mit einem unabhängigen Geschwindigkeitsmodell, welches zur Validierung herangezogen wurde. / The Ice, Cloud and Land Elevation Satellite (ICESat) was the first Earth-orbiting laser altimeter mission in space. The following work is dedicated to the ICESat-altimetry data in order to demonstrate their full potential for the investigation of glaciological implications in polar regions. The primary science objective of the mission was to focus on the mass balances of the Greenland Ice Sheet and the Antarctic Ice Sheet. Both of them play a key role in the Earth's climate system. Firstly, the ICESat elevation profiles covering the Lake Vostok region are analysed in more detail. The Lake Vostok is the largest known subglacial lake in Antarctica to date. Due to a fast and strong degradation of the laser energy, the ICESat elevation measurements are affected by offsets. The estimated offsets between the laser operational periods vary between -7.5 und +13.9 cm. Therefore, they can't be neglected in the view of precise mass change determinations for ice sheets. In addition, a Digital Elevation Model (DEM) of the ice surface topography is generated on the basis of the adjusted elevation profiles. The DEM is analysed in more detail. Furthermore, the DEM forms the basis for the investigation of glaciological implications. In combination with an ice-thickness model and a regional geoid model the hydrostatic equilibrium condition is evaluated. It turns out, that the ice sheet covering the lake fulfils the hydrostatic equilibrium condition within ±1 m for large parts of the lake. Beside this, positive and negative deviations are found in the northern and southern part of the lake. Secondly, ice surface height changes and their temporal variations are inferred for the Greenland ice sheet. This investigation is based on a refined repeat-track analysis in order to exploit the full potential of ICESat's altimetry data. To reduce the influence of the local topography corresponding measurements along the track are fitted to a mathematical model, consisting of three components. For the entire ice sheet a mean surface height trend of -13.0±0.5 cm/yr is determined. The largest changes are identified at the coastal margins of the ice sheet. Using the ice surface height changes long-term volume- and mass-change rates are inferred. For this purpose the density of pure ice is used for the volume-mass-conversion. The overall long-term mass change rate amounts to -209.5±35.6 Gt/yr. This is equivalent to an eustatic sea level rise of +0.6±0.1 mm/yr. A third approach analyses ICESat elevation profiles over the Amery ice shelf. The method is based on a cross-correlation analysis of different ICESat repeat cycle in order to determine the ice flow velocity along the track. This method is applied to reference track 49. The investigation reveals that between 71.7° S and 70.1° S along the reference track, the ice-flow velocity increases from about +0.83±0.09 m/d to +1.02±0.06 m/d. These results are in general good agreement with velocities derived from an independent velocity field.

Bornsjön är Stockholms viktigaste reservvattentäkt och kan tillgodose staden med dricksvatten i flera månader om Mälaren skulle slås ut. Det är därför viktigt att Bornsjön håller en god vattenkvalitet. Under de senaste åren har vattenkvaliteten avseende totalfosfor i Bornsjön försämrats. Hög belastning av fosfor kan leda till övergödning i en sjö. När en sjö är övergödd uppstår ökad syreförbrukning som kan leda till syrebrist. Vid syrebrist frigörs fosfor från sediment och det blir större näringstillgång som bidrar till mer övergödning. Övergödning beror ofta på utsläpp från punktkällor, till exempel från avloppsvattenutsläpp, men kan även bero på diffusa utsläpp från jordbruksmark och skog inom avrinningsområdet. Syftet med examensarbetet var att förstå vilka fosforprocesser som är viktiga för Bornsjönsom ekosystem och med den dynamiska massbalansmodellen LakeMab utvärdera olika realistiska åtgärder för att minska belastningen av totalfosfor. Marken runt Bornsjön ägs av Stockholm Vatten och med resultaten från detta arbete ska Stockholm Vatten få olika förslag på vilka åtgärder som bör prioriteras. Resultat från andra kända modeller har även jämförts med LakeMabs resultat. Studien visade att det är möjligt att reglera belastningen av totalfosfor på Bornsjön genom till exempel införande av vallodling, minskning av åkerareal och genom minskade utsläpp från enskilda avlopp. Dessa olika åtgärder kan kombineras för ökad effekt. Det är även möjligt att sänka totalfosforkoncentrationen i sjön genom att sänka sjöns pH-värde. Detta är dock en åtgärd som inte rekommenderas på grund av att en förändring av det naturliga pH-värdet påverkar ekosystemet. För att i framtiden kunna göra liknande studier med mer tillförlitliga resultat bör provtagningsprogrammet i dikena utökas, speciellt vid kraftig nederbörd då fosforläckaget från marken är större. / Lake Bornsjön is Stockholm’s most important reserve water source and can supply the city with drinking water for several months in case Mälaren would be polluted. Thus it is important to maintain the water quality of Bornsjön. In the last years the quality of the drinking water has in reference to total phosphorus in Bornsjön degraded. High load of phosphorus leads to eutrophication in lakes. When a lake is eutrophicated the respiration increases, which may lead to a lack of oxygen in the water. At reduced conditions of oxygen, phosphorus will be released from the sediments which lead to an increased eutrophication. Eutrophication is often the result of anthropogenic point sources, for example waste water treatment plants, but can also be due to diffuse sources like agricultural and forests within the catchment area. The purpose with this Master degree project was to understand which phosphorus processesare important for Bornsjön as an ecosystem and with the dynamic mass balance model LakeMab evaluate different realistic actions to decrease the load of total phosphorus. Most of the catchment area around Bornsjön is owned by Stockholm Vatten and the aim of this project is to recommend Stockholm Vatten which actions should be prioritized. Also, results from other models have been compared with the results from LakeMab. This study showed that it is possible to regulate the load of total phosphorus to Bornsjön, for example with ley farming, less agricultural area and decreased load from individual sewage systems. These different actions can be combined for an increased effect. It is even possible to lower the concentration of the total phosphorus in the lake by decreasing its pH-value. However, this action is not recommended because a change of the natural pH will affect the ecosystem. To make similar studies in the future with more reliable results it is important to extend the sample scheme for the ditches, especially at occasions with high precipitation which leads to increased phosphorus leakage from the soil.

Neighboring northern Kaohsiung with a dense population of petrochemical and petroleum industrial complexes included China Petroleum Company (CPC) refinery plant, Renwu and Dazher petrochemical industrial plants. In recent years, although many scholars have conducted regional studies, but are still limited by the lack of relevant information evidences (such as odorous matters identification and VOCs fingerprint database), while unable to clearly identify the causes of poor ambient air quality. By sampling and analyzing VOCs, we will be able to understand the major sources of VOCs in northern Kaohsiung and their contribution, and to provide the air quality management and control countermeasures for local environmental protection administration. In this study, we sampled and analyzed the speciation of VOCs and sulfur-containing odorous matters (SOMs) in the CPC refinery plants, Renwu and Dazher petrochemical complexes simultaneously with stack sampling. The sampling of VOCs and SOMs were conducted on January 7th, 14th, and 19th, 2011 (dry season) and May 6th, 13rd, and 23rd, 2011 (wet season). We established the emission source database, investigated the characteristics of VOC fingerprints, and estimate the emission factor of each stack. It helps us understand the temporal and spatial distribution of VOCs and ascertain major sources and their contribution of VOCs. Major VOCs emitted from the stacks of the CPC refinery plant were toluene and acetone. It showed that petroleum refinery processes had similar VOCs characteristics and fingerprints. The fingerprints of stack emissions at Renwu and Dashe industrial complexes varied with their processes. Hydrogen sulfide was the major sulfur-containing odorous matter in all petrochemical plants. Compared to other petrochemical complexes, Renwu industrial complex emitted a variety of SOMs species as well as relatively high concentrations of sulfur-containing odorous matters. The petrochemical industrial complexes in the industrial ambient of VOCs analysis results showed that isobutane, butane, isopentane, pentane, propane of alkanes, propene of alkenes, toluene, ethylbenzene, xylene, styrene of aromatics, 2-Butanone (MEK), acetone, of carbonyls are major species of VOCs. In addition, ethene+acetylene+ethane (C2), 1,2-dichloroethane, chloromethane, dichloromethane, MTBE were also occasionally found. Sulfur-containing odorous matter (SOMs) analytical results showed that major odorous matters included hydrogen sulfide, methanethiol, dimethyl sulfide, and carbon disulfide. The highest hydrogen sulfide concentration went up to 5.5 ppbv. In this study, the species of VOCs were divided into alkanes, alkenes, aromatics, carbonyls, and others. The temporal and spatial distribution of various types of VOCs strongly correlated with near-surface wind direction. The most obvious contaminants were alkanes, aromatics, and carbonyls of the dispersion to the downwind. Generally, the ambient air surrounding the petrochemical industrial complexes was influenced by various pollutants in the case of high wind speeds. It showed that stack emission and fugitive sources had an important contribution to ambient air quality. TSOMs and hydrogen sulfide emitting mainly from local sources resulted in high concentration of TSOMs and hydrogen sulfide surrounding the petrochemical industrial complex. Principal component analysis (PCA) results showed that the surrounding areas of petrochemical industrial complexes, regardless of dry or wet seasons, were mainly influenced by the process emissions and solvent evaporation. The impact of traffic emission sources ranked the second. Chemical mass balance receptor modeling showed that stack emissions from the CPC refinery plants contributed about 48 %, while fugitive emission sources and mobile sources contributed about 30 % and 11%, respectively. The stack emissions from Renwu industrial complex contributed about 75 %, while fugitive emission sources and mobile sources contributed about 17 % and 5 %, respectively. The stack emissions from Dazher industrial complex contributed about 68 %, while fugitive emission sources and mobile sources contributed about 21 % and 2 %, respectively.

The purpose of this dissertation is to develop and evaluate techniques for improvement of seasonal streamflow forecasts in the Upper Rio Grande (URG) basin in the U.S. Southwest. Three techniques are investigated. The first technique is an investigation of the effects of the El Ni??o/Southern Oscillation (ENSO) on temperature, precipitation, snow water equivalent (SWE), and the resulting streamflow at a monthly time scale, using data from 1952 to 1999 (WY). It was seen that the effects of ENSO on temperature and precipitation were confined to certain months, predominantly at the beginning and end of the winter season, and that the effect of these modulations of temperature and precipitation by ENSO can be seen in the magnitude and time variation of SWE and streamflow. The second part is a comparison of the use for snowmelt-runoff modeling of the newly available snowcover product based on imagery from the satellite-borne Moderate Resolution Imaging Spectroradiometer (MODIS) with the long-time standard snowcover product from the National Hydrological Remote Sensing Center (NOHRSC). This comparison is made using the Snowmelt Runoff Model (SRM) in two watersheds located inside the URG basin. This comparison is important because the MODIS snowcover product could greatly improve the availability of snowcover information because of its high spatial (500m) and temporal (daily) resolutions and extensive (global) coverage. Based on the results of this comparison, the MODIS snowcover product gives comparable snowcover information compared to that from NOHRSC. The final part is an investigation of streamflow forecasting using mass-balance models. Two watersheds used in the comparison of MODIS and NOHRSC snowcover products were again used. The parameters of the mass-balance models are obtained in two different ways and streamflow forecasts are made on January 1st, February 1st, March 1st and April 1st. The first means of parameter estimation is to use the parameter values from 1990 to 2001 SRM streamflow simulations and the second means is by optimization. The results of this investigation show that mass-balance models show potential to improve the long-term streamflow forecasts in snowmelt-dominated watersheds if dependable precipitation forecasts can be provided.