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  • 1.
    Eckersten, Sofia
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. Sofia Eckersten.
    Advancing Sustainable Transport Systems: Strengthening environmental considerations and sustainability perspectives in Strategic Choice of Measures2024Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Addressing cross-cutting issues such as climate change, urbanization, andenvironmental degradation in policy and planning is key for transitioning toa sustainable society. In the work of societal and transport systemdevelopment, the integration of environmental and sustainabilityperspectives has never been more crucial. In urban areas, the interconnection between transport and land use is evident, and integrated transport and land use planning plays an important role in promotingsustainable transport systems. However, both the integration ofenvironmental and sustainability considerations in transport planning and the integration of land use and transport planning are complex challenges.This thesis explores the consideration of environmental aspects andsustainability perspectives in strategic transport planning, with a focus onthe Swedish Strategic Choice of Measures (SCM) approach and lessonslearnt from planning approaches in the Nordic countries. The thesis is primarily based on case studies of SCM processes in the Stockholm region. Empirical material has been collected through observations of SCMs involving public officials from the Swedish Transport Administration,municipalities in Stockholm Region, and Stockholm's public transportauthority, as well as through semi-structured interviews, focus groupinterviews, informal interviews and document studies, with a qualitative research approach.The thesis is a compilation of four scientific papers. Three of the papers (1,2, and 4) discuss the SCM process, and in two of the papers (2 and 4), SCM processes in the Stockholm region are used as empirical cases of howstrategic choices of measures have been made in transport and land useplanning. Paper 3 explores and draws lessons from Nordic planning instruments to coordinate transport and land use planning with the aim of promoting sustainable development. The results highlight the difference between engaging and non-engagingenvironmental aspects and advocate for a systems perspective in planning to understand connections and promote holistic solutions. Planning approaches from different Nordic countries, such as the Finnish MAL and the Norwegian Urban Growth Agreements, demonstrate the effectiveness of integrating transport and land use planning through instruments based oncollaboration between transport and land use actors. The results also identify challenges related to fragmented transport and land use planning,and that actors' vary in their engagement when addressing environmental and sustainability considerations in the SCM planning context. Effective collaboration and sustainable choices of measures relies on knowledgeable professionals being capable of interdisciplinary collaborations and innovative thinking, being part of and coordinating the planning process, i.e.SCM. The use of Integrated Landscape Character Assessment (ILCA) can provide a framework for cross-actor collaboration and has the potential to identify multifunctional solutions contributing to a sustainable societal transition. Overall, the results of the thesis emphasize the importance of integrating environmental and sustainability perspectives into transport planning to promote sustainable development.

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  • 2.
    Ligate, Fanuel Josephat
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Hydrogeochemistry of arsenic, fluoride, and other trace elements in groundwater in northern Tanzania: Occurrence, distribution, and impacts on drinking water quality2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The occurrence of arsenic (As), fluoride (F-), and other trace elements (TEs) with potential toxicity in groundwater is a global environmental concern. According to the National water resource mapping database, about 76 % of the drinking water supply in Tanzania is abstracted from groundwater sources. In northern Tanzania groundwater accounts for more than 80 % of the drinking water supply. Albeit the importance of groundwater in northern Tanzania, its quality concerning geogenic contaminants is not optimally understood. The present study focused on estimating the groundwater quality using analytical, geochemical modeling, statistical, and GIS techniques which were carried out to better understand the chemical quality of groundwater in the framework of safe drinking water supply in Tanzania. Fluoride was established as the principal geogenic groundwater contaminant in northern Tanzania, particularly in the Pangani and internal drainage basins, parts of the East Africa Rift Valley (EARV) system. About 8 % and 57.6 % of the water samples collected from Geita and Sanya alluvial plain have indicated F- concentration above the WHO guidelines value (1.5 mg/L) for drinking water. The high F- concentration in groundwater originates from F- rich minerals and ash deposits from the granitic and alkaline volcanic parent rocks. The consumption of elevated concentrations of F- in groundwater has been responsible for dental, skeletal, and crippling fluorosis. In the Lake Victoria basin (LVB) goldfields, As was reported to be the main geogenic contaminant of health concern. The concentration of As in 50 % and 82 % of the groundwater samples from Tarime and Geita respectively exceeded the WHO guidelines (10 µg/L). The high concentration of As in groundwater from the LVB was highly associated with natural geochemical processes as well as gold mining activities. Results from geochemical modeling revealed that As mobilization was influenced by oxidative and/or reductive dissolution of As-containing sulfide and iron minerals, respectively from the parent rocks. The concentrations of other TEs (aluminum, chromium, cobalt, copper, iron, manganese, nickel, and zinc) were observed below the WHO drinking water guideline. The spatial variability of As and F- concentration from drinking groundwater sources was associated with the different groundwater levels, screened depths, and contact time of groundwater interaction with the As and F-- containing rock minerals in the aquifers. Furthermore, irrigation water sourced from the F- contaminated boreholes poses risks of contaminating the shallow aquifers that are easily accessible for human and domestic animals’ consumption. The current WHO recommended guidelines of 10 µg As/L and 1.5 mg F-/L intake for humans are open to further epidemiological scrutiny, especially considering chronic/long-term exposure in the region. The present study highlights the need for large-scale hydrogeochemical and human health risk investigations concerning geogenic contaminants in the region. The findings contribute to the local, regional, and global initiatives toward sustainable exploitation of groundwater resources in conformity with the Sustainable Development Goal (SDG) 6 for universal access to safe water and sanitation for all.

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  • 3.
    Cai, Zipan
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Resources, Energy and Infrastructure.
    Towards a Scenario-based Spatial Dynamic Modeling for Predicting Urban Land Use Change: Planning Tools and Comparative Analysis2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    As global urbanization progresses, cities worldwide are growing in size, which leads to many economic, environmental, and management challenges. Recent advancements in spatial data analysis and algorithmic geography have also led to the development of various urban model-based planning support systems (PSS) for urban planning. These PSSs aim to assist urban decision-makers in understanding urban information and collaborating on planning to address urban development challenges. Advanced urban planning concepts are, however, always multidisciplinary, multi-situational, and continuously evolving. In addition to the development of more advanced urban information and communications technology (ICT) and management, planning concepts that promote urban health and sustainable development are needed to meet residents’ physical, spiritual, and social needs, and promote more sustainable lifestyles. These factors create the need for a more rigorous methodological and theoretical foundation to apply PSS to urban planning at the microscale. 

    A scenario-based spatial dynamic modeling approach is proposed in this thesis to address this research gap, allowing for a more precise matching of local policy scenarios and desired development patterns for practical planning support purposes. Several urban development scenarios and their potential impacts are explored by analyzing future urban land use changes. The establishment of this planning support approach effectively integrates spatial analysis, simulation model, policy revision, and participative planning. First, the thesis examines the rules and correlations underlying land unit transformations resulting from human-land interactions in spatial dynamic models by investigating mechanisms driving changes in urban land use. Second, a series of possible urban development simulations are generated through several case studies that employ a variety of representative cities with different urban contexts as model test sites including Nanjing in China, Stockholm in Sweden, and Chicago in the USA to evaluate their validity and practicality. Socioeconomics, ecological systems, and urban amenities are among the research themes that provide a more realistic and practical view of urban development. Last, visualization of the simulation results and quantitative information analyses and transformation is utilized to arrive at recommendations for revising planning policies and promoting sustainable development strategies.

    The challenge of adapting successful experiences of urban transformation from one city to another is considerable and cannot be achieved by merely replicating single projects or developments. An important goal was to address this challenge by developing general methods for model-assisted planning and then exploring their applicability and scalability across different contexts and geographical regions. Obtained results confirm that prioritizing industrial and transportation sectors in urban development is the most significant factor contributing to the rapid expansion of cities. This allocation of resources leads to the development of supporting infrastructure and employment opportunities, thereby attracting more people and industries to urban areas. Limiting the expansion of built-up areas and preserving green spaces is a desired measure to protect natural assets and the composition of cities and mitigate the negative environmental consequences of urbanization. Moreover, it is found that there are significant differences in the spatial and temporal needs and dependencies of residents in different areas with respect to natural and social amenities, providing a basis for future land development in residential and commercial areas of a city. Based on these findings, policymakers can more readily test and evaluate “what-if” scenarios using a process-based approach to avoid uncontrolled urban growth. In spite of limitations and uncertainties, the tools presented in this thesis are relevant for urban policymakers to enhance stakeholder interaction and consensus building in the decision-making process. This work has demonstrated the methodological steps for the implementation of these tools, as well as the general potential benefits of dynamic modeling for sustainable city planning and development.

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  • 4.
    Kimambo, Vivian
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering. The University of Dodoma, United Republic of Tanzania.
    Groundwater defluoridation by natural minerals: Understanding the process of fluoride removal from drinking water sources in Tanzania2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Fluoride (F-) concentration in drinking water is one of the water quality parameters in countries with high concentrations in groundwater sources. Natural minerals have shown considerable effectiveness in F- removal. In this study, the performance of the locally available natural minerals, such as bauxite, magnesites, and gypsum, have been investigated at the laboratory scales and through modelling for F- removal from drinking groundwater sources in Tanzania. Batch experiments were carried out to examine the optimum conditions for F- removal by the calcined bauxite, magnesite, and gypsum. X-ray fluorescence spectroscopy (XRF) characterization showed that Al2O3, MgO, and SO3 were the major oxides in bauxite, magnesite, and gypsum, respectively. The experimental data for the three treated adsorbents fitted well with the Freundlich adsorption isotherm and the pseudo-second-order kinetics. The values of ∆G° and ∆H° indicate that the F- adsorption on bauxite and magnesite surfaces was spontaneous and endothermic. The randomness described by ∆S° at the solid–liquid interface was increased during the adsorption processes. While for gypsum, the reaction was spontaneous and exothermic, where the randomness at the solid–liquid interface decreased during the adsorption processes. At optimum conditions, calcined bauxite (400 °C), magnesite (650 °C), and gypsum (350 °C) lowered the F- concentration from 8.27 mg/L to 1.02, 0.233 and 1.99 mg/L, respectively. Bauxite and gypsum lowered the pH of water from 9.38 to 6.74 and 7.41, respectively. Magnesite raised the pH from 9.38 to 10.12, which is above the World Health Organization (WHO) (6.5 - 8.5) and Tanzania Bureau of Standards (TBS) (6.5 – 9.2) drinking water standard; therefore, pH adjustments are needed before water can be used for drinking. The Bed Depth Service Time (BDST) plot showed that the service times for F- adsorption on the calcined bauxite and magnesite surface increased with bed depth. The critical bed depths (Zo) for bauxite and magnesite obtained were 7.21 and 8.28 cm, respectively. The lower value of the kinetic rate parameter (Kα) for bauxite (1.43E-5 L/mg s) and magnesite (1.50E-5 L/mg s) highlighted that the breakthrough occurs in short beds; therefore, deeper beds are required to avoid breakthroughs. The experimental results and model predictions have helped to compare the adsorption processes as well as contrast their performance and sustainability for F- removal using the bauxite, magnesite, and gypsum in the drinking water resources in Tanzania. The adsorption results and the overall cost analysis show that the cost of calcined bauxite and magnesite is low compared to other available adsorbents; therefore, they can be used in F- removal from water.

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  • 5.
    Paul, Seema
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Strategic Sustainability Studies.
    Lake Hydrodynamics and Pollution Transport under Climate Change: The Case of Lake Victoria2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    A very small part of the total earth’s water is freshwater (only 2.5 %). Unfortunately, due to climate change and pervasive manmade activities, surface freshwater quality in many places of the world has become degraded. This is manifested in the Rift Valley lakes, a series of lakes in Eastern Africa that runs from Ethiopia in the north to Malawi in the south. Water quality degradation in the Rift Valley lakes is driven by various factors, including water quantity and scarcity, pollution and contamination, nutrients loading, and general water use by industry and society. In particular, Lake Victoria, the world’s second-largest freshwater body and the largest tropical lake, has seriously polluted near lakeshore areas, which is a great regional development problem causing misfortune for millions of people.

    This dissertation contributes new insights into lake hydrodynamic processes and pollution transport in shallow lakes through developing more accurate models to understand the complex processes of water quality degradation. Based on empirical data this thesis developed systematic methods to consider lake bathymetry, lake flow, water level verification, water balance, hydro-climatological processes, transport and dispersion of pollutants and nutrient particles. The data-driven hydrological model of Lake Victoria that is developed in the thesis considers hydro-meteorological and climatological data, river discharges and outflow, wind speed and direction, atmospheric deposition, nutrient loading, concentration of pollutants and nutrients, and remote sensing satellite data. The thesis illustrates the power of numerical and hydrodynamic methods that uses one- and two-dimensional mathematical equations (1D and 2D) to model the three-dimensional (3D) behaviour of shallow lakes over time. 

    The results indicate that the lake hydrodynamics of Lake Victoria are heavily influenced by lake bathymetry and regional weather patterns and are thus connected to increasing climate variation. The hydro-meteorological processes, verified by empirical data on precipitation, lake flow and lake water levels, show that extreme weather events are responsible for changing the characteristics of lake water balance, changing seasonal variations, and exhibiting strong correlations among water level and hydro-meteorological data. The model of the movement of pollutants and nutrient particles shows how pollutants and nutrients travel within Lake Victoria and where they concentrate in the lake and its sediments. The wind hydrodynamic modelling shows that the wind, along with hydrodynamic stability, plays an important role in pollution flow patterns and that pollutants can be transported from shallow parts, when they leave rivers and shorelines, to deeper lake areas. The hydro-climatological model demonstrates the crucial interdependence between hydrodynamic processes and climatological factors at the catchment scale of Lake Victoria. 

    The numerical models and calculation methods that have been developed in this dissertation represent additional contributions to hydrodynamic research and can be used to investigate hydrodynamic processes in other lakes. The thesis contributes to UN Sustainable Development Goals related to water security, drinking water, food, and health. A potential area of application lies in supporting analysis and mitigation of pollution and climate change effects and more generally aid in the natural resource governance of this vital African lake.

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  • 6.
    Bergame, Nathalie
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Strategic Sustainability Studies.
    More than flowers!: On the transformative practice of commoning urban gardens2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Urban gardening is a burgeoning practice that increasingly takes place in urban centres of the world. In this thesis, I define urban gardens as socially mediated yet materially rooted phenomenon through which social and material relations are elaborated in common through time and space. And, I understand the garden not as an object, but as an entity that emerges out of the relationships between gardeners and non-human nature. I draw on the recent turn in commons’ theory shifting the focus on commoning, and not, as in earlier commons research, on the commons as structure. Grounded in the case of a new wave of urban gardening initiatives in the City of Stockholm, Sweden, I examine how commoning urban gardens transforms the people doing the gardening, the commoners, including their agency, subjectivity, and identity. But also how the commoners shape their structural environment.

    Ontologically, I deploy a critical realist social theory perspective which means that I acknowledge the a priori existence of structures and agency and their conditioning by each other relationally. This means that I (i) look at how spatial, societal and temporal structures affect the agency of gardeners (ii) how those gardeners are affecting their structural environment through the practice of urban gardening, as (iii) well as how their agency is conditioned by the practice.

    I deploy a qualitative mixed methods approach, comprising of interviews, a questionnaire, observations, participatory dissemination and poetic inquiry and find that high green public space availability in the City of Stockholm, municipal policies in favour of urban gardening, and a rich historic culture of associational life in Sweden provide a supportive context for urban gardening. I find that commoning gardens in public spaces bring together people and build collective relations despite a context of neoliberal individualisation. It emancipates individuals by reorganising the management of urban space, and changes how the City of Stockholm is urbanising towards more collective organising. Among those that partake in urban gardening, some remain grounded in a need-fulfilment (“I want to garden to be more in nature”), whereas others change through the commitment of being part of an urban garden, become political and collective subjectivities with a social identity that overlaps with their personal identity. This shows that structures condition people differently, and do not deterministically affect agency in the same way for everyone. Yet many remain entirely excluded from the new urban garden commons, such as people of colour, indicating that urban gardening, while it can be transformative for those that partake, is reproductive of structures of whiteness in urban public space. At the same time, historical structures of patriarchy in public spaces are being transformed. At the expense of the unpaid social reproductive labour of female gardeners, who make out the majority of urban gardeners, public green space is being transformed into spaces of care and community.

    I conclude that urban gardening deserves a critical analysis of its immanent contradictions to safeguard against unwanted and unintentional reproduction of injustices and for the promotion of practices that emancipate and empower people.

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  • 7.
    Nathaniel, Hanna
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Insights to beachcast management on Gotland, Sweden: An Industrial Ecology perspective on waste-resource ambiguity2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Beachcast or beach wrack, washed-up algae and seaweed, used to be a highly sought-after agricultural resource (fertiliser and soil conditioner) in coastal communities around the world before being replaced by chemical fertilisers, but considering the talks of a circular bio-economy – can we reintroduce it? 

    Since the abandonment of beachcast in agriculture, the amount of beachcast has significantly increased as an effect of eutrophication caused by the use of chemical fertiliser, and the material is commonly considered waste. Meanwhile, soils have degraded and need the multiple positive effects on agroecosystems that beachcast could provide. So, while harvesting the biomass serves to remedy the adverse ecosystem effects on marine ecosystems (from excessive organic material, i.e. macroalgae blooms), beachcast could potentially contribute to more sustainable food production.

    Sadly, it is not simple. This potentially symbiotic process infers uncertainties regarding soil cadmium accumulation, coastal ecosystem effects, and other challenges - and despite multiple studies and attempts at a waste-to-resource conversion of beachcast, the challenges remain unsolved, and a novel take on the topic seems necessary.

    On Gotland, Sweden, with a historical tradition of using beachcast in agriculture, a modern governance system for management has emerged from a national policy subsidising beachcast harvesting, which has partly come to connect the marine and agricultural domains, among other actors. In this case, beachcast harvesting is subsidised as a measure to curb eutrophication and reduce the detrimental effects of excessive beachcast, a phenomenon present in the Baltic Sea and many other coastal regions worldwide that are caused by an accelerating nutrient accumulation at sea and sediment stocks. So, by further applying beachcast as a fertiliser in agriculture and horticulture, a practical example of a regional land-marine nutrient loop could be created to make beachcast management more sustainable. However, multiple challenges need to be addressed. 

    This thesis and case study of Gotland, Sweden, presents an illustrative example of contemporary beachcast governance and management that provides knowledge and insights to support policy development and more sustainable beachcast management practices. insights for policy that can support the development of more sustainable management practices. This is done by using semi-structured interviews to understand the beachcast governance and management practices based on stakeholder perceptions (Paper I), performing a cost-benefit analysis of beach-cast harvest to assess the economics of closing land-marine nutrient loops in the Baltic Sea region (Paper II), conducting a cultivation experiment to predict future trends in soil cadmium concentration from applying beachcast as fertiliser (Paper III), and mapping regional variations in chemical composition of fresh and composted beachcast to consider future treatments (Paper IV). 

    The results show that to overcome the challenges and achieve more sustainable practices, the following measures and considerations are essential: further supporting continued experimentation and monitoring of marine ecosystems to handle the harvest-hesitation caused by the uncertainties associated with marine ecosystem effects; sampling of composted material and careful agricultural use to remedy the waste-resource ambiguity associated with Cd contamination; and a continued subsidy and cross-sectoral collaborations to abide managerial and financial responsibility for beachcast activity.   

    In this in-depth and transdisciplinary case study with a mixed-methods approach, the findings point to a theoretical and practical incongruity In seeking a waste-to-resource conversion of beachcast, which indicates that beachcast cannot compete with commercially viable products in today's intensive agricultural regime. Instead, agroecology, an alternative pathway according to FAO, appears to be a more promising context for beachcast to be acknowledged and receive the necessary investment to resolve its ambiguous resource status. 

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  • 8.
    Mäkivierikko, Aram
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Sustaining Sustainable Behaviours of Citizens by Creating Value in Their Everyday Life2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Over 60% of global greenhouse gas emissions derive from household consumption patterns. To reach the 1.5-degree target set in the Paris Agreement, new interventions to influence household behaviours are needed. This thesis examined two areas, household electricity consumption and waste sorting, where behaviour plays a large role. To change behaviour, households need information and feedback regarding their consumption, but in an era of information overload it is difficult to reach individuals. This thesis explored whether households can be better reached by a service that creates value for its users, so that feedback is noticed and acted upon over a sustained period. Specific objectives were to: (1) identify needs of citizens that could be addressed with a local digital service and develop such a service; (2) design and develop elements of the service to promote selected sustainable behaviours affecting household electricity consumption and household waste sorting; and (3) evaluate whether these elements can improve awareness of sustainability matters and promote pro-environmental behaviour among residents.

    To fulfil objective (1), a local social network for neighbourhoods was designed and developed. A phone survey in Stockholm Royal Seaport confirmed low neighbour interaction, while focus group interviews in Hammarby Sjöstad identified specific local information and communication needs. To fulfil objective (2), a subset of design principles identified from the literature was used to design feedback for the local social network. The feedback was developed into a prototype through workshop and focus group discussions. To fulfil objective (3), residents were provided with feedback and interventions in two pilot studies in Stockholm, a 15-month study on electricity consumption involving 281 students at KTH and a 12-month study on waste sorting involving 61 households in Stockholm Royal Seaport having an automatic waste collection system. The study on electricity showed a 3.3 %-unit peak-hour reduction for the intervention group and 46 %-unit reduction for saving participants. Average participation in peak load reduction was 3 months, but some stayed for almost the entire period, indicating potential for long-term engagement. Incentives were not necessary, but improved outcomes. The waste study found increased plastic sorting among app users, but also challenges in data collection and analysis. Overall, the value-creating approach can be useful if user needs are met correctly, and reaches a larger user group with feedback than conventional energy apps.

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  • 9.
    Habib, Md. Ahasan
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering. NGO FORUM FOR PUBLIC HEALTH.
    Increasing the impact and sustainability of safe drinking water supply systems in rural Bangladesh: Randomized experiments with interventions in project life cycle2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Access to safe drinking water is a global challenge, as reflected in Sustainable Development Goal 6. In Bangladesh, bridging the gap between those with safely managed drinking water and those with improved sources is a pressing issue. This study estimates causal relationships between interventions in the project life cycle and their impact on sustainable access to safe drinking water in rural areas. A series of Randomized Control Trials (RCTs) were conducted across different regions of Bangladesh over 15 years of tubewell construction programs to provide  arsenic  free  safe  drinking  water.  The  RCTs  evaluated  changes  to decision-making  processes,  contribution  requirements,  and  maintenance practices. Community participation in decision-making processes can enhance the  impact  and  sustainability  of  safe  drinking  water  programs.  Requiring communities to contribute financially or through labour does not necessarily increase program impact, and it can lead to reduced take-up, and decreased cost- effectiveness though it may increase sustainability. Community water sources are less effective than expected due to contamination introduced during collective use and issues related to transport and storage: they help to mitigate arsenic exposure  but do not effectively  address faecal  contamination. Disinfecting tubewells  with  a  weak  chlorine  solution  reduced  faecal  contamination. Caretakers standard cleaning practices do not generally adhere to best practices and may worsen water quality. However, training caretakers in best practices proved highly effective in reducing Escherichia coli contamination, significantly improving water quality. Despite some imperfections in caretakers' recall and compliance, these results highlight the crucial role of proper cleaning and maintenance practices in reducing exposure to faecal contamination in rural Bangladesh, ensuring access to safe drinking water. The study highlights the power of RCTs in addressing complex causal questions related to safe drinking water access. While valuable insights have been gained, the study emphasizes that numerous unanswered questions remain, underscoring the ongoing need for research in this critical field. In summary, this study provides important evidence about how to improve project design and thereby increase access to safe drinking water in rural Bangladesh.

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  • 10.
    Irunde, Regina Filemon
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering. Chemistry department, University of Dar es Salaam, Tanzania.
    Treatment of arsenic contaminated drinking water from the sources around the gold mining areas of Geita and Mara, Tanzania: Removal efficiency of locally available materials, bauxite, gypsum and magnesite2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In recent years, high arsenic (As) levels of about 300 µg/L have been reported around the gold mining areas of Geita and Mara regions within the Lake Victoria basin (LVB) in Tanzania. During a sampling campaign at Geita and Mara, the groundwater and surface water samples revealed the presence of high As concentrations as well as Fe and sulfide. Several wells are abandoned because of odor due to high content of sulfide, as well as red color, due to high iron content. About 53% of the analyzed As water samples exceeded the WHO guideline for drinking water. The release of As is primarily attributed to the weathering of sulfide minerals like arsenopyrite related to gold mining activities. In some parts of the LVB, an increasing number of cancer cases are being reported, and clinical investigations are now on the national agenda to identify the possible causes. Water treatment using bauxite, gypsum, and magnesite shows promising results, especially bauxite and magnesite, which could lower As concentrations to below 0.1 µg/L. Both bauxite and magnesite worked efficiently on As removal even at higher concentrations above 5 mg/L, while gypsum is preferable for treatment of low As concentrations. Furthermore, magnesite has a unique chemical character of influencing other materials to have high efficiency of As removal; however, it raises the pH of the water up to 10. Addition of 5 g/L magnesite to water containing 5 mg/L As, could lower the As concentration to below 10 µg/L within 30 min. The As removal increased with dosage and contact time up to 98 % in 4 hours, which is in agreement with Visual MINTEQ simulation. The performance of calcined magnesite, and gypsum fitted well with Freundlich adsorption isotherm, which indicates the presence of chemical reaction as controlling factor for As removal, while bauxite fitted Langmuir isotherm indicates monolayer surface coverage. The kinetic reactions were observed to follow pseudo-second-order. The statistic obeys linear regression with R2 ranging between 0.7 and 0.9. The artificial neural network revealed pH as a most influencing parameter for As removal from water. The mini-scale column revealed that a flow rate of 0.5 – 1 mL/min for 30 min gave an adsorption capacity ranging between 0.07 and 0.14 µg/g, which follows Thomas linear model with rate constant of kTH of 29.48 to 211.25 mL/min µg. The release of elements from spent magnesite, gypsum, and bauxite, such as magnesium (Mg), aluminum (Al), iron (Fe), and calcium (Ca) were found to be below WHO standards after water treatment. However, the desorption process of As from spent magnesite and gypsum was a challenge, which means there was formation of strong bond between Mg-O-As and Ca-O-As. This study is based on 5 papers that provide significant insights to the scientific community, policymakers, and the community living around As contaminated areas to learn about the occurrences of As and simple remediation techniques evaluated in this study.

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  • 11.
    Wretling, Vincent
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Sustainability Assessment and Management.
    Bending the Curve – the Role and Interplay of Municipal Energy Planning and Municipal Spatial Planning for Climate Change Mitigation in Sweden2022Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The global climate is changing rapidly, which pronounces the need for imminently bending the curve of greenhouse gases emissions. The local authorities have been recognised as key actors in this decarbonisation, due to their wide-ranging responsibilities, including different mandates for local planning. The Swedish municipalities are no exception in this regard. In contrast, they stand out as being especially critical for Sweden’s efforts to reach climate neutrality in 2045 and multiple other sustainability objectives, since they are instructed to conduct municipal energy planning regarding supply and distribution of energy, have a monopoly on spatial planning and have been given a veto right for larger wind power establishments. There is, however, limited knowledge regarding the municipalities’ planning processes and institutional capacity building for handling climate change mitigation in their municipal planning. The overall aim of this compilation thesis, comprising five scientific papers, is to contribute with new knowledge regarding the role, process and interplay of municipal energy and climate planning, municipal spatial planning and municipal wind power planning for responding to the need for rapid decarbonisation, in order to identify pathways forward for building the municipalities’ institutional capacity. The thesis has a mixed methods approach comprising of semi-structured interviews, focus group interviews, participant observation, a survey, statistical analyses, and multiple document analyses of either cross-sectional or longitudinal character that involves elements of both quantitative content analyses and thematic analyses. 

    When synthesising the findings from Paper I-V, it is evident that the municipalities are responding to the climate crisis in multiple different ways. This includes that a proactive strategic energy and climate planning practice with the aim of reducing climate impact has emerged from the sectoral energy planning tradition. However, the impact assessment practice is deficient within municipal energy and climate planning, especially if the planning is conducted in a non-statutory form, in spite of it being indicated that impact assessment can facilitate the consideration of synergies and conflicts between different sustainability objectives as well as enabling to illuminate local benefits of climate action. Moreover, the municipalities have been integrating numerous different strategies for reduced climate impact into their Comprehensive Plans, relating to energy production, distribution and use, transport, and land use, and the findings suggest that such consideration of energy and climate aspects in the Comprehensive Plans have increased in the recent decades. This integration of climate change considerations into Comprehensive Plans has largely been spurred by the existence of a municipal energy and climate strategy or similar, which has enabled a two-way policy integration between these two policy spheres. The presence of energy and climate strategic competence within the municipal concern is an associated vital feature, since this facilitates the influx of knowledge through the participation in different regional-local and inter-municipal networks, which can then be disseminated internally and utilised in the comprehensive planning process. There is also a need for municipal officials to be given time and resources to interact with politicians in order to mobilise support and create a mandate for action.

    Simultaneously, the results illuminate that many municipalities are struggling with building sufficient institutional capacity for addressing climate change mitigation in their energy and climate strategic planning and their strategic spatial planning. This was manifested for example in the form that the adoption of both energy and climate-focused policy documents and wind power plans followed the temporal patterns of the presence of state-funded financial incentives and that more than one-fourth of the municipalities not having adopted an energy and climate-focused policy document during the studied twelve-year time span. This has also rendered in a more reactive municipal decision-making in relation to the municipal veto for wind power deployment, with implications for its legitimacy and public participation. Given the centrality of the municipalities, it is deemed vital to further promote the process of building institutional capacity for responding to the climate crisis in their municipal planning and decision-making. Increased continuity in the energy and climate strategic planning process, comprehensive planning process and wind power planning process could facilitate building support for integrating different strategies related to climate change mitigation in their planning and contribute to organisational learning. Moreover, the three modes of planning could be further interlinked, for example, by establishing objectives regarding greenhouse gases emissions and renewable electricity production in the energy and climate domain, which brings implications for the strategic spatial planning, and by initiating processes simultaneously and in an integrated fashion. If municipalities come to recognise the potential of a more proactive strategic-thinking SEA process, this could be another vehicle for increased sustainability consideration early in the process, when there is a window of opportunity for influencing the plan’s content to the greatest extent. Overall, this can lead to a more sustainability-led municipal planning, which can contribute to bending the curve of greenhouse gases emissions, while simultaneously providing synergies across other sustainability objectives. 

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    PhD kappa, Vincent Wretling
  • 12.
    Ijumulana, J.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering. DAFWAT Research Group, Department of Water Resources Engineering, College of Engineering and Technology, University of Dar es Salaam, Dar es Salaam, Tanzania.
    Spatial variability of geogenic contaminants in drinking water sources: Insights into hydrogeological controls, geospatial data for safe water supply and groundwater resource management2022Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The presence of geogenic contaminants in drinking water is a major health concern in many parts of the world. The interaction of groundwater with different rock types and sediments in the natural geochemical environment play an important role in controlling their mobility. Due to limited resource allocations, water quality investigations are mostly limited only to the drinking water sources serving the communities. As a consequence, most aquifer systems remain unexplored in terms of groundwater quality through conventional methods. The present study aims to investigate the status of groundwater quality in the nine drainage basins of Tanzania focusing on the occurrence of fluoride (F¯) and other potentially toxic elements especially in the northern development zone (NDZ). The specific objectives were to model the spatial distribution of geogenic F¯- in groundwater systems and the health risk among the population as well as to evaluate the key influencing hydrogeological factors for the observed variability in F¯ concentrations in water sources using modern geospatial methods and technologies. Both literature and community perspectives indicate a serious problem in terms of F¯ in the Internal, Pangani, and Lake Victoria basins in the NDZ where the prevalence of mild to severe fluorosis is a health risk among the communities dependent on groundwater for drinking. In order to understand the spatial variability, machine learning methods were developed during this research by applying a combination of the concepts of spatial statistics, geostatistics, different Geographical Information Systems (GIS) tools as well as non-parametric methods to study the occurrence of geogenic contaminants in groundwater systems. Spatial statistical methods such as Moran’s I statistics and GIS tools revealed two positive significant high-high spatial patterns along the Pliocene-recent volcanic and the Mozambique belt as well as around Meru and Hanang’ stratovolcanoes in the northeast and southwestern part of the study regions, respectively. The positive low-low spatial patterns were determined around the major and minor rift valley escarpments both in the west and east of the East African Rift Valley (EARV) graben and around the stratovolcanoes within the graben. Other potentially toxic elements were found in elevated concentration around the Meru stratovolcano creating another risk of health concern to the communities which depend on such sources of drinking water. Factors controlling the spatial variability of fluoride in groundwater included, in the descending order, the mineralization, topography, tectonic processes, pH and water exchange between hydrogeological units during water movement. Other factors included depth to groundwater, well depth, screen depth and irrigation practices in the Sanya alluvial plain. The spatial heterogeneity of geological characteristics may lead to the spatial variability of various geogenic contaminants at spatial scales besides several other factors like topography, soil type, surface water-groundwater interaction, climate, volcanic activities, tectonic processes.The results of this study are important to the water safety planning implementation in the naturally contaminated aquifer systems especially in the EARV regions and volcanic areas.

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  • 13.
    Ddiba, Daniel
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Sustainability Assessment and Management. Stockholm Environment Institute.
    Implementing resource recovery from urban organic waste in low- and middle-income countries: Tools to support planners and policy makers2022Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Globally, there is increasing awareness of the importance of applying circular economy principles to the management of organic waste streams through resource recovery. This is especially relevant in urban areas of low- and middle-income countries which are going to host a significant part of population growth over the next few decades. Circular economy approaches for sanitation and waste management can provide incentives to improve infrastructure and consequently contribute resources for water, energy and food that power urban livelihoods. 

    This thesis aims to contribute new knowledge, methods and tools that are applicable as decision support for the planning and implementation of circular approaches to the management of organic waste streams. The research questions in the thesis focus on three aspects of resource recovery from organic waste streams; (1) how decision support tools estimate its potential to contribute to a circular economy, (2) the governance conditions that facilitate or impede its implementation, and (3) its sustainability implications. The research in this thesis employed a mixed methods approach including literature reviews, semi-structured interviews, field observations, workshops, quantitative modelling, diagnostic governance assessment, scenarios as well as quantitative and qualitative sustainability assessment. The research was operationalized in three case study locations: Chía (Colombia), Kampala (Uganda) and Naivasha (Kenya). 

    The findings reveal the quantities of resource recovery products like biogas, compost and black soldier fly larvae that can be obtained from the organic waste streams collected in a large city, as well as the available decision support tools that can be used to address various aspects of resource recovery in sanitation systems. In the case study locations of Naivasha and Chía, the existence of entrepreneurial initiatives for resource recovery, the available platforms for collaboration among relevant local stakeholders and the relative affordability of resource recovery products are highlighted as factors enhancing governance capacity to implement resource recovery from organic streams. On the other hand, the inadequacy of monitoring and evaluation systems and the relatively low availability and transparency of information emerged as some of the factors impeding governance capacity. Through a framework that is developed and applied to the Naivasha case, the thesis also identifies the environmental gains that can be made from implementing resource recovery from organic waste streams, as well as the potential negative social impacts that need to be mitigated by local stakeholders. The extent to which various decision support tools address the sustainability implications of resource recovery from sanitation systems is also discussed.

    By providing new insights on resource recovery from organic waste streams in the case study locations, the tools and frameworks in this research demonstrate approaches that can be applied in a policy and practice context to offer decision support for the implementation of resource recovery from organic waste streams. This is particularly relevant for urban areas in low- and middle-income countries whose stakeholders wish to explore the potential of resource recovery from their organic waste streams, to undertake a diagnostic assessment of their governance capacity and to assess the sustainability implications of implementing more circular approaches in their sanitation and waste management systems.

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  • 14.
    Morén, Ida
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Resources, Energy and Infrastructure.
    The influence of multiscale hyporheic flow on solute transport: Implications for stream restoration enhancing nitrogen removal2022Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Stream water that flows into and out of streambeds is called hyporheic exchange flow (HEF).It continuously interacts with groundwater and thereby affect the water quality of local streamreaches as well as downstream recipients by providing an environment where solutes andenergy can be retained and degraded. Because of anthropogenic activities, many streams andrivers have been physically, chemically and biologically degraded during the last centuries andnatural functions, such as HEF, have to some extent been lost. The general aim of this thesiswas to advance the understanding of the physical controls of HEF in small streams and toinvestigate how HEF influences solute reactive transport in streambeds and surface waternetworks before and after stream restoration. To reach the aim, the consistency and deviationbetween HEF parameters evaluated with two common approaches were investigated in tendifferent alluvial streams with low discharge, shallow depth and moderate slope. The twoapproaches were: 1) developing and using a deductive hydro-mechanical model to assessed therelationship between the multiscale streambed geomorphology and the reach scale averageHEF parameters, and 2) evaluating HEF parameters from in-stream tracer tests using a 1Dlongitudinal transport model. The relatively high consistency between the approaches connectstheories that previously have been relatively fragmented and provides a tool for upscaling(parameterizing) of HEF in solute transport models over stream networks based onindependent observations of stream topography, streambed sediment properties and in-streamhydraulics. Applying the modelling framework at the network scale and supporting it withcomprehensive datasets provided information regarding physical mechanisms and spatialvariability of HEF as well as its influence on longitudinal solute transport. Specifically, thefractal properties of the water surface profile were shown to represent the average HEF velocitywell. Furthermore, hydraulic head variations over shorter wavelengths (0.1-5 m) were found todrive the main part of the HEF and the static hydraulic head variations dominated over dynamichydraulic head variations as drivers of HEF in all investigated streams. Moreover, this thesishighlights the importance of the hyporheic zone as a bio-chemical and mechanical filter forstream water. It shows that common engineered stream restorations can influence HEF andimprove the water quality in local stream reaches as well as downstream recipients. Specifically,the thesis presents exact solutions to the nitrogen transport, which shows that the mass removalof nitrogen in the hyporheic zone is either transport or reaction limited and that the maximalremoval rate corresponds to an optimal hyporheic residence time and a typical denitrificationDamköhler number. The results also show that potential exists to reduce the agriculturalnitrogen load to the Baltic Sea by stream restorations that optimize the hyporheic residencetimes. However, the large spatiotemporal variability in the potential between reaches stressesthe importance for further studies on which processes that are driving HEF under specifichydromorphologic conditions and careful design of stream restoration measures at each localstream reach.

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  • 15.
    Liljenström, Carolina
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Sustainability Assessment and Management.
    Life cycle assessment of transport systems and transport infrastructure: Investigating methodological approaches and quantifying impacts at project and network levels2021Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Reducing greenhouse gas emissions from the transport sector is a key challenge to reach global climate targets and limit global warming to below 2 ºC. The use of life cycle assessment (LCA) may provide knowledge about the environmental impacts of transport systems so that emission reduction measures can be identified.

    The aim of this thesis is to investigate how LCA can contribute with knowledge that can be used to support specific decisions in the context of transport system policy and planning, to demonstrate how LCA can be conducted at project and network levels, and to contribute with knowledge of direct and indirect climate impact and primary energy use of the Swedish transport infrastructure and the Swedish transport system at a network level.

    The thesis includes four papers that contribute to achieving this aim. Paper 1 demonstrates an approach for the identification of hotspots in Swedish road, rail, air, and sea transport infrastructure at a network level. Paper 2 demonstrates this approach for the full transport system at a network level, including national and international freight transport and passenger travel by road, rail, air, and sea. At the project level, Paper 3 investigates how LCA can be used as decision-support in choice of road corridor, considering prerequisites of data availability and usefulness of results for decision-making. Paper 4 maps approaches used to quantify impacts of the maintenance stage in 92 project-level LCAs of road and rail infrastructure and discusses their applicability in policy and procurement.

    Paper 1 estimated that the annual climate impact of Swedish transport infrastructure is about 3 Mtonne CO2 equivalents and that the corresponding primary energy use is about 27 TWh. Road and rail infrastructure contributed to 90% of these impacts. Additional hotspots identified were reinvestment of roads and railways and production of asphalt, concrete, and steel. Paper 2 estimated that the annual climate impact of the Swedish transport system is about 40 Mtonne CO2 equivalents and that the corresponding primary energy use is about 196 TWh. Road transport and aviation together accounted for 85% of these impacts. Indirect impacts were significant, accounting for about a third of the impacts. The main causes of indirect impacts were fuel production for road passenger travel and manufacturing of passenger cars.

    Paper 3 found that LCA-based models used in early planning should include generic data that are nation specific (preferably approved by the national road authority) and that can be replaced by project specific data when needed. Further, both traffic and infrastructure should be included at a level of detail that allows the identification of improvement measures and the assessment of uncertainty in the results. Results should be presented relative to a reference alternative and complement results from other decision-support used in planning. Paper 4 found a variety of approaches to quantify impacts of the maintenance stage in LCA. The analysis period was often determined based on the infrastructure’s service life. The maintenance frequency was commonly estimated based on the current practice of maintenance in a region or on performance prediction modelling. Only two of the reviewed papers included the effects of climate change on results of the LCA. How the approaches can be implemented in decision-making depends on their abilities to be standardised for use in procurement and to incorporate multiple scenarios.

    Stakeholders involved in transport system policy and planning can use these results as support in considering life cycle impacts in their decision-making practice to reduce environmental impacts in line with national and international targets.

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  • 16.
    Azzi, Elias
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Biochar systems across scales in Sweden: An industrial ecology perspective2021Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Biochar – the carbon rich residue derived from biomass pyrolysis – is recognised as a potential solution to remove carbon dioxide from the atmosphere, while simultaneously delivering socio-environmental benefits through biochar use as a material. Perceived as a sustainable innovation, biochar has raised interest throughout the world. Sweden has witnessed a rising interest for biochar over the past decade, leading to investments in modern biochar production capacity and the development of various biochar-based products. However, as for any emerging technology, it is necessary to study its environmental performance in a systematic manner to guarantee that environmental expectations meet reality, and to enable science-based policy support.

    This thesis examined the energy, climate and environmental impacts of biochar production and use, supporting on-going and future projects in Sweden. Four case studies were designed, set respectively in Stockholm, Nyköping, Helsingborg and Uppsala areas. The case studies analysed biochar production at various scales, from different biomass feedstocks, and biochar use in urban and rural applications. The main method applied was life cycle assessment, complemented with material flow analysis and energy systems modelling. In addition, a framework was developed to conceptualise and classify environmental effects of biochar in a life cycle perspective. 

    The results showed that biochar systems can deliver more climate change mitigation than conventional bioenergy when energy systems are already rather decarbonised and if biochar stability is high. Biochar carbon sequestration provided the main climate change benefit, but smaller additional benefits were obtained from some material uses of biochar. When compared with reference systems, biochar solutions lead to shifts of burdens between sectors and environmental impact categories. It is possible to integrate pyrolysis to both large district heating networks and decentralised heating systems, but it will lead to a net increase in biomass consumption and related environmental impacts, relative to direct combustion of biomass. In the second half of the century, the need for management of biochar-containing soil masses will arise from today’s emerging urban applications. 

    The case studies illustrated new uses of biochar and quantified several environmental benefits from biochar use. However, gaps remain between biochar effects present in the public discourse and their quantification in life cycle assessment. These differences were attributed to variability in the biochar effects, lack of knowledge, or inappropriate accounting framework. Overall, the thesis stresses the importance of analysing the potential of innovations to contribute to environmental goals by using parametrized life cycle models, depicting multiple contexts, and striving to identify suitability conditions rather than providing a definitive static answer.

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  • 17.
    Francart, Nicolas
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Sustainability Assessment and Management.
    Decision support for the implementation of low-carbon measures in the building sector2021Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The building sector is responsible for about a fifth to a third of global greenhouse gas (GHG) emissions. Therefore, a successful mitigation of GHG emissions over the entire life cycle of buildings is particularly important to achieve climate targets such as the Paris Agreement. This requires measures at multiple levels and from multiple actors, including broad roadmaps for the building sector, policies and regulations, certification and green procurement criteria, and new practices among property owners, architects, developers and manufacturers. Such initiatives are sometimes supported by the introduction of tools and methods to quantitatively assess environmental performance. Life cycle assessment (LCA) is one such tool, used in certification and increasingly in procurement and regulation. To reliably steer towards lower environmental impacts, environmental performance assessment tools need to be precise, accurate and well-adapted to the decision contexts in which they will be used. While a tool like LCA can provide valuable decision support, some methodological issues remain unresolved, and its effect in real decision situations remains understudied.

    This thesis aims to support decisions and initiatives to mitigate environmental impacts in the building sector, with a particular focus on fulfilling ambitious climate targets. The thesis addresses two facets of this overarching issue. First, it investigates challenges to the implementation of relevant sustainable practices, at various levels and in various decision contexts. Second, the thesis considers to what extent environmental performance assessments could steer towards low environmental impacts (and in particular low global warming potential (GWP)).

    The thesis is based on a combination of quantitative and qualitative approaches. At a strategic level, a quantitative model of buildings’ GWP linked to four backcasting future scenarios is used to spotlight issues for the fulfilment of ambitious climate targets. This helps challenging existing paradigms and images of the future about how buildings are constructed and operated. At a more operational level, multiple qualitative studies explore barriers to specific practices to mitigate environmental impacts, and the roles played by environmental performance assessments. An interview- and workshop study explores important factors for the adoption of space sharing, as a way of optimizing the use of indoor space. A survey- and interview study highlights challenges to the use of requirements by Swedish municipalities to promote low-GWP construction. A third interview study shows how various artefacts mediate work with sustainable design in housing projects. Finally, the thesis addresses more directly the accuracy of environmental performance assessments, and investigates how choices of data and method related to maintenance and replacement affect LCA results, exemplified for façade materials.

    The modelling of buildings’ GWP in backcasting scenarios helps challenge current paradigms by drawing attention to some less-discussed issues, such as reducing embodied emissions (including by avoiding new construction) as well as the demand for indoor space. Space sharing can help optimizing the use of indoor space, but several factors limit its adoption. It requires different practices among building users and property managers, including different business models and performance metrics considering occupancy. Ambiguities in national legislation and municipal plans regarding the status of shared and multifunctional buildings also hinder space sharing initiatives (e.g. unclear rights and responsibilities of tenants and property owners, conflicting requirements for fire safety or ventilation, etc.). Similarly, the thesis highlights important regulatory ambiguities regarding to what extent municipalities can set requirements to promote low-GWP construction. Environmental performance requirements in construction also entail barriers related to limited in-house skills, access to data, time and resources. Using such requirements would first require bridging skill and data gaps. Similar barriers are highlighted regarding the use of LCA in public housing projects. In such projects, artefacts such as national regulations, local development plans and internal requirements of the housing organization enforce a certain level of work with sustainable design while limiting the range of design options. Other artefacts simplify the design work and provide standardized default options. In such cases, design choices that strongly influence environmental performance are taken upstream of the project, when these criteria, requirements and default options are developed.

    The thesis highlights ways in which quantitative assessments of environmental performance could directly influence building design and management, e.g. through the introduction of environmental performance criteria in regulation and procurement. Besides challenges related to skill, data, time and resources mentioned above, the thesis draws attention to the variability of LCA results due to choices of method and data sources. In the particular case of maintenance and replacement processes, the choice of reference study period (RSP) influences the relative significance of these processes, and longer RSPs favor more durable products. Discrepancies exist between different sources for service life data, indicating a need for more reliable data. The use of a round-up or annualized number of replacements makes little difference in average, but can lead to different outcomes in specific cases. This shows a need to carefully harmonize methodological choices as LCA becomes used more and more broadly in procurement and building regulation.

    Furthermore, the thesis also draws attention to more complex effects of environmental performance assessments in housing projects. Widespread certification systems can become de-facto definitions of sustainability for actors, influencing design even in projects that are not certified. Environmental performance assessments can hide or reveal certain aspects of sustainability. Widely used assessment tools can act as “black boxes”, where criteria for what constitutes a sustainable building are hidden and no longer contested. This process helps operationalize sustainability in building projects. However, it can lead to some important aspects being disregarded. For instance, conventional energy performance metrics are often normalized for floor area, ignoring occupancy and space efficiency. On the other hand, quantitative assessments can also highlight important aspects of the multifaceted issue of sustainability. The thesis exemplifies this by using a quantitative model of buildings’ GWP to draw attention to key mitigation strategies, and by reviewing energy metrics highlighting occupancy and space efficiency.

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  • 18.
    Mojarrad, Babak Brian
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Resources, Energy and Infrastructure.
    Multi-Scale Surface Water-Groundwater Interaction: Implications for GroundwaterDischarge Patterns2021Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Rivers and aquifers are continuously exchanging water, driven by processes that occur on various temporal and spatial scales, ranging from small streambed features to large geological structures. The interaction between these two components occurs in permeable sediments below the stream channel, called the hyporheic zone. This zone is an important ecotone in which water, energy, and solutes originating from groundwater and stream water mix. The exchange fluxes through the hyporheic zone are controlled by a distribution of hierarchically nested flow cells of different sizes that are generated by a spectrum of spatial scales of the hydraulic head condition. Thus, a multiscale mathematical approach is required to reach a comprehensive understanding of the hyporheic exchange processes. Therefore, this thesis investigates the roles of regional groundwater flow and hyporheic fluxes in a nested flow system within the streambed sediment. Next, the study assesses the importance of regional and local parameters in generalizing the surface water and groundwater interaction. This division of the top-boundary condition in two scale-intervals of the sub-surface flow is arbitrary but facilitates the analytical procedure. The regional groundwater flow field is evaluated using numerical modeling, accounting for the site-specific landscape morphology and geological heterogeneity of a Swedish boreal catchment. An exact spectral solution is applied to the hyporheic flow with account taken to local streambed topography fluctuation. Combinatorial sampling of the modeled flow data and a Monte Carlo simulation are used in a sensitivity analysis to address the uncertainty in hydrostatic and dynamic head contributions to the hyporheic flow field. Then, the impact of the regional groundwater and the hyporheic flows on the nested flow system in aquatic sediment are studied through superpositioning of the flow fields. This is an efficient approach to analyze the nested flow system because the impact on individual scale intervals can be evaluated separately. Additionally, the impacts of streamflow discharge intensity on hyporheic exchange flow fields are investigated through field investigation. In this study, the hyporheic fluxes velocity at the streambed interface were generally at least one order of magnitude higher than groundwater flow velocity. This reflects the domination of hyporheic fluxes at the streambed interface, leading to significant impacts on the discharge of deeper groundwater through the hyporheic zone. Significant effects were found in flow travel time, direction and discharge areas at the streambed sediment. Thus, the upward groundwater flow contracted near the streambed surface and discharged in a fragmented pinhole pattern at the sediment–water interface. The results also indicated that the magnitude of groundwater flow and the heterogeneity of the subsurface sediment (i.e., the depth decaying hydraulic conductivity of streambed sediment) controlled the depth of hyporheic exchange flow in aquatic sediment. Furthermore, the increased stream flow intensity led to a wide range of hyporheic flow residence times in which temperature was used to evaluate stream segments with gaining and losing conditions.

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  • 19.
    Ringenson, Tina
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Strategic Sustainability Studies.
    Mobilising digitalisation to serve environmental goals2021Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Human development is currently leading to destruction of the stability of the earth system upon which we depend for our survival. In other words, it is unsustainable. At the same time, urbanisation and digitalisation are progressing at a rapid pace. Digital technologies have a potential to decrease environmental impact from cities and urban lifestyles. Transport and mobility is an important part of urban life, and it has been suggested that digital technology can improve urban transport performance in both accessibility and sustainability. Mobility as a Service (MaaS) is a relatively new concept for provision of mobility services through a digital platform, sometimes together with digital accessibility services that lower the need to travel (Accessibility as a Service – AaaS). It has been suggested that MaaS could offer a real alternative to the privately owned car and lead to more sustainable mobility. However, its real effects in practice are still not well known.

    This thesis aims to create knowledge to guide public and private actors in developing digital technologies and using digitalisation to support environmental goals, especially regarding urban mobility. The results are structured around three parts. The first part explores strategies and digital services for municipalities that want to use digital technology to support environmental goals. The second part presents requirements for MaaS and AaaS to support environmental goals for urban mobility. To do so, they should reduce travelling overall and reduce environmental impact per kilometre travelled through enabling better modes of transport and lower vehicle emissions. It also suggests that a functional physical infrastructure for public transport and bicycling is important if MaaS are to support environmental goals. The third part identifies important knowledge gaps to explore, if digital services are to support environmental goals. The relationship between digital services, urban form, and sustainability implications is brought up as an important subject for future research, as well as how to ensure that MaaS fulfil the previously identified requirements.

    Finally, I discuss how to ensure that digital services and MaaS serve environmental goals. There are sometimes grave uncertainties regarding the real effects of various services. Although this makes future effects difficult to predict, it also suggests that investments need to be done strategically, and that data of effects need to be carefully collected and evaluated. Public and private actors both have responsibilities to ensure that digital services fulfil environmental goals. However, it is important not to only look at how to solve specific problems today. To support urban sustainability, we need to think about what kinds of cities we want. We do not have to focus digital services on streamlined, seamless and instant access to things no matter where they are. They can also support urban lifestyles of less focus on physical ownership and daily travelling, and more on positive experiences of sustainable modes of travel and of the local community.

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  • 20.
    Johansson, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Strategic Sustainability Studies.
    A Shift in Urban Mobility and Parking?: Exploring Policies in Relation to Practices2021Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The transport sector is associated with many environmental challenges, including carbon dioxide (CO2) emissions. Research indicate that CO2 emissions should decrease by at least 50 % per decade in order to be in line with the Paris Agreement, and the transport sector is highlighted as a particularly challenging sector. Sweden, which is the case study in this thesis, has a goal of reducing CO2 emissions from the transport sector with 70 % between 2010 and 2030. This target is, however, not likely to be met if current trends continue. New technology will probably not be enough to reach the target, and car ownership and car travel will probably also have to decrease. Furthermore, many households do not have access to cars, and do not benefit from policies that facilitate car use and car ownership. The purpose of this thesis is to critically analyse policy measures on parking and mobility in metropolitan areas in Sweden with the aim of being in line with the CO2 emission goals set by the Paris Agreement, as well as investigating how the aims of the Paris Agreement can be met with a backcasting study. All studied policy measures highlight the need to shift focus from physical infrastructure to accessibility. In each case, however, current practices and conditions render a transition more difficult.

     

    The first paper in the thesis studies the Swedish Transport Administration (STA) mandate to finance different measures. The STA states the importance of reducing the need to travel and making more efficient use of existing infrastructure, and stipulates that these types of measures should be considered before new infrastructure investments. However, the STA has a limited mandate to finance measures with the aim of reducing the need to travel, which results in ambiguous signals to, and frustration among, regional STA officials. This paper demonstrates that making the STA’s mandate more function-oriented would facilitate a transition in line with the sustainable mobility paradigm.

    The second policy measure discussed in this thesis is the shift from minimum parking requirements, where developers are obliged to build a minimum number of parking spaces in order to obtain a building permit, to flexible parking requirements, where the number of parking spaces provided depends on the local context, and where other mobility services may replace the need for parking. The second paper in this thesis follows two blocks of flats built with flexible parking requirements. Car ownership has decreased in both blocks of flats, and car use has decreased in one of the blocks of flats. Furthermore, car sharing membership and use have increased considerably. However, the process of leaving a car dependent social practice is slow and the conditions (e.g. the technology; and ways of finding, booking, and paying for services) need to be relatively stable for the practice to grow. Other policies may also be needed for emerging social practices to grow. Some of these policies have been implemented in Stockholm (e.g. congestion charges, on-street parking fees, extension of public transport and bicycle infrastructure). However, there is also a trend in the opposite direction; such as new urban highways. Future interventions could be made open to residents in adjacent properties, if more people are to be attracted to the mobility services.  

    The third paper in this thesis discusses the feasibility of using a new parking management tool; “Parking Benefit Districts”, in a European context (Stockholm, Sweden). In a Parking Benefit Districts program, on-street parking charges are implemented, increased or extended, and the resulting revenues are returned to the areas where the charges were imposed. Citizens, or other stakeholders, then participate in deciding how to use these revenues. The underlying intention is to increase acceptance of parking charges, as on-street parking charges may be considered necessary by city planners but are unpopular among citizens and other stakeholders. This thesis shows that there are no legal barriers to implementing a Parking Benefit District programme in Sweden, but there are some limitations as to how revenues can be used. Moreover, Sweden does not have this planning tradition and the programme may not be perceived as legitimate. Another important issue is equity and participation, e.g. it is important to consider who to include and how to include them.

    The fourth paper is a target-oriented backcasting study. The paper depicts a future image for parking and mobility for the city of Stockholm that is in line with the CO2 emission goals in the Paris Agreement, and then examines how to plan for parking and mobility in order to steer towards this future image. The paper points out that current parking standards (the flexible parking standard discussed in Paper II) is far from being in line with the Paris Agreement, and emphasizes the necessity of a different planning approach. The paper also presents a path of development thought to be in line with the Paris Agreement. 

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