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  • 1.
    Chen, Yuanying
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Land-Sea Interactions in the Coastal-Marine System of the Baltic Sea under Hydro-Climatic Variability2020Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis investigates a few important component processes for understanding and quantifying eutrophication in the Baltic Sea, that include characterization of nutrient loadings from land, water flow in the sea under changing climate conditions and transport of solutes originating from different locations along the coast. Furthermore, this study aims to improve our understanding on how processes from land (the nutrient loading conditions) and the sea (transport dynamics and water quality) couple to determine the fate of nutrients in the sea and the water quality in a selected localized coastal area, the Himmerfjärden Bay.

    Comprehensive data are compiled as a basis for numerical simulations. An open source tool for oceanographic studies FVCOM is used to simulate flow and transport processes in the Baltic Sea. Hydrodynamic simulations are verified in terms of temperature, salinity and water level for the year 2005. Results show that most of the investigated Swedish watersheds along the coastline are dominated by subsurface legacy sources, the loads of which are positively and linearly correlated with river discharges. Moreover, subsurface legacy sources are less likely to decrease over time compared with the current surface sources. The Baltic Sea has a stable flow structure considering flux directions between basins, while the flux magnitudes between basins are mainly determined by different wind conditions. The spreading patterns in the sea with solute released from different coastal areas are similar when the released amounts are comparable, even though different cases have different source input and water flow conditions. The overall spreading patterns in the sea are generally dominated by the total mass of released solute. Local transport dynamics and patterns around the coast differ greatly for different cases and are determined by the local flow conditions. Different water quality indicators are influenced by different land-based or sea-based measures for water quality improvement. The dry-cold hydro-climatic condition is the most favorable for improving the water quality and elevating the ecological status in the Himmerfjärden Bay.

    Based on this investigation, varying hydro-climatic factors impose important influence on the different component processes of nutrient loading from land to the sea. For example, the change of river discharges from land in the future would influence the total load into the sea from subsurface legacy sources, and finally influence the general spreading patterns of nutrients in the sea. The change of wind conditions would affect the flow and transport dynamics at local scale and flow fluxes magnitudes between marine basins at the sea scale. Change towards a dry-cold condition would be beneficial for the water quality and lead to improvement of coastal water quality, while the change towards a wet-warm condition will be generally unfavorable for improving the water quality. Clearly more comprehensive studies are needed based on the component processes considered in this thesis, for mapping water quality and eutrophication long-term trends in the Baltic Sea with confidence that is sufficient for effective mitigation measures and policies. 

  • 2.
    Freitas, Flavio L. M.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Sustainability Assessment and Management.
    Brazilian public protection regulations and the preservation of ecosystem services and biodiversity2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Brazil is significant for sustaining ecosystems services and biodiversity of global importance. However, the expansion of forestry and agriculture to supply national and international markets often results in loss of ecosystem services and biodiversity. Public protection regulations play a crucial role in setting limits for agricultural expansion. This thesis aims at improving the understanding of the potential impacts of prevailing policies in the preservation of ecosystem services and biodiversity associated with the native vegetation in Brazil. The Land Use Governance Assessment (LUGA) model was developed to simulate the implementation of existing public protection regulations, in particular, the Brazilian Forest Act.

    The results suggest that command and control regulations do not protect about 28 % of the above-ground carbon in Brazil. The regularisation process of undesignated land is expected to expand protection to an additional 18 % of the above-ground carbon stocks, leaving about 10 % of the carbon stocks unprotected. On the other hand, the preservation of viable populations of several threatened mammal species is highly dependent on an urgent expansion of protected areas in the Cerrado and Caatinga biomes. Furthermore, the results from this thesis indicate that offsetting legal deficit of native vegetation may have little or no additional effects on the protection of native vegetation. The potential loss of forest protection due to reduced legal reserve requirements in the Amazon could potentially range from 6.5 Mha to more than 15 Mha.

    There are critical gaps in the land use policies in Brazil that threaten the preservation of ecosystem services and biodiversity associated with native vegetation. Market-driven mechanisms can potentially contribute to filling this gap, protecting nature beyond the legal requirements. Yet, additional regulations may be necessary to improve the efficiency of the trading system of legal deficit of native vegetation among farmers, ensuring environmental and socio-economic functions of this system, and effectively balancing production with conservation.

  • 3.
    Hamisi, Rajabu
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Filtration System For On-Site Wastewater Treatment: Experiences From Modelling and Experimental Investigations2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Many on-site wastewater treatment systems in Sweden are not sustainable in terms of treatment efficiency, nutrient recycling and economics. Achieving reliable and sustainable systems to meet on-site wastewater treatment demands requires comprehensive field investigations of the performance of novel technologies. This thesis investigated the performance of a new leading-edge technology for on-site wastewater treatment in a real field environment in northwest of Baltic Proper Sea, Sweden. The system integrates septic tank treatment technology with a package treatment plant (PTP) and a sequencing batch subsurface flow constructed wetland (SBCW). The investigation combined three approaches: field monitoring, laboratory-scale column experiments and process-based modelling, to provide a better understanding of system performance, predict contaminant retention and test system response to various environmental factors, design scenarios and operational conditions.

    The overall results indicated that the entire system is efficient in removing total phosphorus (83%), biological oxygen demand (BOD7, 99%) and Escherichia coli bacteria (89%). It is less efficient in total inorganic nitrogen removal (22%). Mean concentration of phosphorus (0.96 mg/L) and pH (8.8) in effluent from the entire system were found to be below the Swedish threshold values for on-site wastewater discharge. This indicates that the system could be reliable and sustainable technology for on-site wastewater treatment in cold climate conditions.

    A complementary three-dimensional (3D) model developed using COMSOL Multiphysics® software proved to be a useful and rapid tool for predicting the behaviour of complex hydraulic dynamics. It provided valuable insights into the spatial and temporal variability in sorption processes caused by changes in different wastewater treatment system design parameters, environmental factors and modes of operation. Through process-based modelling, a reactive filter material with longer lifetime and a SBCW design that improved the sustainability of on-site wastewater treatment system were successfully identified.

    It was concluded that long-term performance of reactive filter materials in PTP systems can be achieved when the system is loaded intermittently with low influent contaminant concentrations (<3 mg/L). Optimum phosphorus and nitrogen removal in SBCW can be achieved by manipulating drainage pipe placement and feeding mode, to enable longer contact time and artificial aeration conditions.

  • 4.
    Earon, Robert
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Groundwater resources in hard rock coastal terrains: Insights into heterogeneity and spatial variability2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Challenges regarding water security in hard rock coastal regions with limited soil cover are: a seasonal absence of recharge during times of peak residency, heterogeneity and variability of the fracture network, close proximity to saline water sources and spatially inconsistent storage and extraction. In areas where it is not feasible to connect residents to municipal water systems, a better understanding of the resilience of reservoirs is needed. The purpose of this study is to investigate and describe the spatial nature of hydraulic data in these types of terrains and present several novel GIS-based groundwater tools with the intent of increasing local water security and aiding in sustainable water resources management. Methods used in this study include groundwater balance modelling and conceptual groundwater storage modelling, as well as a combination of parametric and non-parametric statistical methods such as ANOVA, PCA, correlation and semivariogram analyses. Specific capacity estimates from the Geological Survey of Sweden’s well archive grouped by age or rock type showed very little autocorrelation and in assumed homogeneous geological regions showed statistically significant differences when arbitrarily grouped along a lineament. Estimates of kinematic porosity based on surface fracture data were found have statistically significant correlations with the well data. A GIS-based multivariate prediction tool for assessing Groundwater Resources Potential (GRP) was found to have statistically significant correlations with well data. The GRP method was then combined with a conceptual groundwater storage model and was subsequently found to have statistically significant correlations with chloride concentrations in well quality tests. The storage model was found to have a spatially-dependent sensitivity, meaning that different assumptions within the model had varying effects on the model depending on the geological settings. Incorporating the storage model into a spatial groundwater balance model was then compared with groundwater level time series data over a period of two years, where it was found to have a good explanative capacity and RMSE values of the storage ratio (0.06 to 0.34). Additionally, a soil depth model was developed, tested and found to produce promising results in regions with frequent rock outcrops, where up to 86% of estimates were within 2 m of actual soil depths. Conclusions from this study illustrate the need for a spatial approach to groundwater resources in these types of terrains, and demonstrate a strong potential of several new tools for quantity, capacity and vulnerability estimates to increase water security in a changing climate.

  • 5.
    Bakyayita, Grace Kizito
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering. Makerere University, Kyambogo University.
    Batch Sorption Studies of Aqueous Cadmium and Lead from Contaminated Water onto Selected Biosorbents2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Groundwater, wastewater, surface runoff and surface water samples from Lake Victoria basin, Uganda was assessed for trace metals contamination. Untreated, base-treated and peroxide-treated biosorbents from Albizia coriaria, Coffea canephora, Cyperus papyrus, Erythrina abyssinica and Musa spp were investigated for removal of selected trace metals from contaminated water in batch studies. The assessed shallow groundwater and surface water was contaminated with iron and manganese. Selected speciation studies using Visual MINTEQ showed that in leachates from Municipal dumpsites 74% of the metal ions were bound to DOM, 13% were free ions and 13% were in inorganic forms moreover for urban streams 37% of the metal ions were bound to DOM, 44% were free ions and 19% were in inorganic forms. The metal levels in surface water, landfill leachate and surface runoff showed elevated levels and revealed increased risks to environmental health. Risk analysis based on the Swedish EPA showed that varied risks of negative effects in 30% – 76% of the sample sites ranging from high to increased risk in surface water whereas the results from Bio-met tool showed potential risk to toxicity effects of Cu2+, Ni2+, Zn2+ and Pb2+ in 15.3% - 30.8% surface water samples and 8.3% - 62.5% groundwater samples. Batch sorption studies revealed that the optimal conditions for Cd2+ and Pb2+ ions uptake were; pH 3.5 – 5.0 for contact time 3.0 – 3.5 hours and biosorbent dosage 10 – 12.5 g/L. Base-treated biosorbents showed 10 – 17 % sorption enhancement for Cd2+ ions and 1.6 – 2.3 % uptake reduction for Pb2+ ions. The biomass negative potential for binding base cations was in the order; Musa spp. > A. coriaria > E. abyssinica and base treatment reduced DOC leaching from biosorbents in the order; E. abyssinica > A. coriaria > Musa spp. Speciation studies showed that more ions were complexed to DOC in solutions at various pH levels. The maximum sorption intensities for both Cd2+ and Pb2+ ions uptake onto biomass occurred for low initial metal concentration; 5 mg/L. Freundlich model best fitted data for Pb2+ ions ions uptake whereas Temkin model fitted the sorption data for Cd2+ ions onto both treated and untreated biomass. For peroxide treated biomass, the maximum sorption efficiencies for both Cd2+ and Pb2+ ions were between 95.2 – 98.7% for C.canephora, 79.9 – 92.2% for Musa spp. and 42.0 – 91.3% for C.papyrus in non-competitive media and 90.8 – 98.0% for C.canephora, 56.4 – 89.3% for Musa spp. and 19.5 – 90.4% for C.papyrus in competitive media. The Langmiur model fitted non-competitive sorption data with 0.769 ≤ R2 ≥ 0.999 and the Freundlich model fitted competitive sorption data with 0.867 ≤ R2 ≥ 0.989. The pseudo second order kinetic model fitted the sorption data for Cd2+ and Pb2+ ions for untreated, peroxide treated and base treated biomass with 0.917 ≤ R2 ≥ 1.000. The sorption of trace metals was a complex potentially monolayer chemisorption with heterogeneous surface properties exhibited. In competitive sorption, sorption suppression effects observed were greater for Cd2+ than Pb2+ ions. The comparative studies on sorption performance presented agreement and no significant difference between the untreated and base treated biosorbents. 

  • 6.
    Pechsiri, Joseph
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Nutrient Recovery as an Added Benefit to Harvests of Photosynthetic Marine Biomass: A Holistic Systems Perspective on Harvesting Marine Microalgae, Cyanobacteria, and Macroalgae2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    As a result of increasing environmental burdens from anthropogenic activities andresource scarcity, interest for the development of solutions utilizing photosyntheticmarine biomass has also been increasing in both academia and industries. Medium tolarge scale production and harvest of photosynthetic marine biomass have beenpracticed to achieve numerous services, including improving tourism industries,production of biofuels, and production of food/feed. However, few studies haveevaluated the potential for nutrient recovery as an added benefit to the aforementionedservices and the potential environmental burdens of such solutions from a holisticsystems perspective. This thesis, therefore, sought to determine the nutrient recoverypotential of harvesting photosynthetic marine biomass at industrial scales whileassessing the environmental burdens from a holistic systems perspective. Techniquesinvolving life cycle inventory and analysis, input-output analysis, growth modellingand experimentation, energy analysis, and assessment of greenhouse gas emissionsfrom a life cycle perspective were used to assess the potential environmental burdensof large scale harvest of photosynthetic marine biomass.This study employed five real world case studies of five different photosynthetic marinebiomass species at various geographical locations across the globe. Each case wasassessed to determine the potential to recover nutrients while evaluating the potentialenvironmental burdens from an energy and greenhouse gas perspective. Each casecontains unique specific details and therefore methods applied were case specific.Results showed that nutrient recovery potential existed in most cases with the exceptionof one case. Cases evaluated for their potential environmental burdens showed thatlarge scale harvest of photosynthetic marine biomass is resource intensive regardless ofspecies but showed mixed results from an energy perspective. The key findings of thisthesis were that a) the potential for nutrient recovery was estimated in both large scalecultivation and large scale wild harvest of photosynthetic marine biomass, b) from anenergy and biomass harvesting perspective, the viability of industrial harvests ofphotosynthetic marine biomass were found for both large scale cultivations and wildharvesting of biomass blooms, and c) scale of operations is an important factor towardsevaluating the environmental performance of photosynthetic marine biomassproduction systems.

  • 7.
    Stigsson, Martin
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Structural Uncertainties of Rock Fractures and their Effect on Flow and Tracer Transport2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    A clear understanding of solute flow and transport through the network of fractures in the rock mass is essential for accurate long-term safety assessments of geological storage of hazardous waste. In a discrete fracture network (DFN) model, flow and transport of solutes are described by chains of flow paths through single fractures, each of which contributes to the total flow and transport properties of the rock mass. Hence, knowledge of the flow and transport properties of each single fracture is essential for accurate safety assessment.The void space that forms a fracture is a derivative of the roughness of the bounding surfaces and the normal force acting on the fracture and is hence dependent on accurate measurement of these properties. As all measurements are associated with uncertainties stemming from e.g. instrument imprecision, external disturbances and human factors, the measured value of the properties will not be single values, but probability distributions. Depending on the set of values drawn from these distributions, interpretations of flow and transport properties of sheared fractures in crystalline hard rock will vary.This thesis examines how flow and transport properties through single fractures are affected by uncertainties in fracture orientation and in roughness. By inferring the orientation and its uncertainty from the fracture intercepts in boreholes, a probability space for the orientation of the fracture is obtained. For a given stress state, this uncertainty in orientation will result in a distribution of normal stresses acting on the fracture. The roughness of the fracture and its uncertainty can be inferred from the small intersecting surfaces of the rock core, if the resolution is sufficient and the surface is representative of the fracture. The inferred roughness affects the correlation structure of the void between the two surfaces defining the fracture and, together with the distribution of normal stresses, produces different flow paths and hence different properties of flow and transport of solutes. Depending on the parameter combinations, the median and variance of the aperture field will change, as will the correlation structure of apertures. Since the flow and transport properties depend on the geometrical framework, the uncertainty will affect path length, travel time, transport resistance and flow-wetted surface. Higher normal stress acting on the fracture will typically result in longer travel times, longer travel lengths, higher transport resistance and larger flow-wetted surface. A rougher fracture will typically result in shorter travel times, longer travel lengths, lower transport resistance and smaller flow-wetted surface. The conclusion is, hence, that uncertainties in the geometric framework will affect flow and tracer transport properties.

  • 8.
    Dawkins, Elena
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. Stockholm Environment Institute.
    Sustainable consumption for policymakers: measuring, learning and acting2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Current patterns and levels of consumption are a key driver of unsustainable resource use and pollution, which contributes to global environmental degradation. Rapid reductions in environmental pressures are required to avoid irreversible loss of fragile ecosystems and social and economic crises. Consumption must become sustainable. Governments have an essential role to play in delivering this. The aim of this thesis is to examine three aspects of the policymaking process on sustainable consumption – measuring, learning and acting – and the links between them. Each aspect has a linked objective.

    1. Measuring: Assess existing and novel techniques for calculating the environmental pressures of consumption that enable government to measure and monitor a country’s progress towards sustainable consumption
    2. Learning: Determine whether – and, if so, how – consumption-based indicators might better support policymaker learning on sustainable consumption
    3. Acting: Identify ways in which governments can enhance their actions to support sustainable consumption

    The research is presented in six papers and organised in three parts: one for each objective. Parts 1 and 2 investigate current and future opportunities for policymakers to measure the environmental pressures linked to their country’s consumption, what these mean for achieving sustainable consumption and whether consumption-based indicators support learning about sustainable consumption. These parts are based on the Swedish experience of sustainable consumption. Part 3 examines various sustainable consumption interventions and what these could mean for government action in the future. This part draws on examples from several countries. Qualitative and quantitative methods are used to answer these questions. These comprise systematic review and mapping, macro-environment economic modelling and analysis, interviews, workshops and focus groups.

    The results provide a number of insights. First, novel consumption-based measurements for Sweden highlight the scale of the challenge involved in achieving sustainable consumption and the importance of increasing the policy applicability of indicators. Second, while indicators provide some learning for policymakers, their contribution to changing existing practices and navigating political or institutional barriers is limited. The learning potential of indicators is constrained by institutional environments. Instead, learning must be structured and enabled by institutions. Third, with regard to the actions studied, increased government involvement appears a necessary and, to some actors, desirable option. Nonetheless, a number of barriers to and enabling factors for policy action to promote sustainable consumption must be considered. In terms of the connections between the three elements of measuring, learning and acting, what might first appear to be a linear relationship is in reality far more complex. Measurement does not necessarily lead to learning – and learning is not always followed by action. Policymakers act without the level of knowledge they would like while indicators remain unused and, in some cases, are even rejected. Learning comes from practitioners’ involvement in action, as well as research into the actions themselves, the problem and solutions. Understanding government efforts on measuring, learning and action to promote sustainable consumption offers insights into how these multiple factors might contribute, separately and together, to more sustainable consumption.

  • 9.
    Pereverza, Kateryna
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Resources, Energy and Infrastructure.
    Steering sustainability transitions? Modular participatory backcasting for strategic planning in the heating and cooling sector2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Fostering sustainability transitions in the heating and cooling sector is a necessary and urgent issue. Steering mechanisms can enable coordination of actions by different actors towards common sustainability goals. Previous studies have identified requirements relevant for such steering frameworks, but have not specifically addressed planning in the highly contextual heating and cooling sector. Participatory backcasting (PB) possesses a number of relevant characteristics for use as a planning framework in this sector, but its adaptability and potential impact first need to be addressed.

    This thesis sought to advance strategic planning in the heating and cooling sector by improving the adaptability, transparency and reflexivity of PB processes and extending their impact beyond individuals directly involved, so-called social scales of impact. Key research objectives of the present work were to: (1) develop a strategic planning framework for the heating and cooling sector based on PB and examine its adaptability to local contexts, (2) develop methods for scenario development, selection and analysis to allow for co-informing between modelling and participatory processes within PB-based strategic planning, and (3) identify factors that could influence the social scales of the impact of participatory strategic planning processes.

    Objectives 1 and 2 were pursued in a multiple case study involving transdisciplinary research over one-year PB-based planning processes in Bila Tserkva, Ukraine (Case I) and Niš, Serbia (Case II). The social scales of impact (Objective 3) were studied in a single case – a Swedish project aimed at advancing the practice of long-term planning in regions ‘Region 2050’ (Case III). In all cases, both theoretical and empirical research were conducted.

    The study proposes a novel framework, modular participatory backcasting (mPB), for strategic planning in the heating and cooling sector. The framework integrates principles of modularity, participatory modelling, and transdisciplinarity. The results of mPB implementation in Case I and Case II suggest that the framework has acceptable adaptability to local contexts. Greater reflexivity and transparency in the scenario development, selection and analysis were achieved by developing a morphological method and implementation of participatory modelling approaches. Finally, boundary spanning individuals, collaborations and institutional plurality were identified in Case III as important factors for broadening the social scales of impact of participatory strategic planning processes.

  • 10.
    Börjesson Rivera, Miriam
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Strategic Sustainability Studies.
    What is a sustainable everyday life?: Exploring and assessing the sustainability of everyday travel, sharing and ICT.2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In a world where the general trend is unsustainable consumption patterns, can sustainable everyday life be enabled? This thesis sought to expand the knowledge base for policies and measures for sustainability, based on the assumption that consumption can be viewed as the outcome of practices in which people engage in their day-to-day life. The thesis addressed the overall aim by examining the following questions: How can information and communication technology (ICT) practices contribute to sustainable everyday practices? How can sharing practices, ICT-based and other, contribute to sustainable everyday practices? and How can travel practices, ICT-based and other, contribute to sustainable everyday practices?

    Empirical and conceptual studies revealed that ICT has become a fundamental and integral part of everyday practices and that digitalisation is a tangible material companion with implications for sustainability. ICT changes practices in ways that can be both positive and negative from a sustainability perspective. These second-order effects need to be addressed early when developing ICT solutions/services.

    ICT has also contributed to development of the sharing economy, by making sharing easier and scalable. However, although some sharing practices can contribute to overall sustainability, others could display a high potential and risk, simultaneously. It is therefore important to identify and mitigate negative effects and exploit the full potential of sustainable sharing activities from a policy perspective.

    Everyday travel is the outcome of people’s social practices. Travel practices are therefore ultimately interlocked with other practices and spatially and temporally structured. It can thus be quite difficult for city dwellers, although not impossible, to fit in new ways of carrying out everyday city travel rather than existing travel practices. New travel practices should be viewed as complementary if there are no other enabling factors at play, such as convenience, pricing, policies and/or infrastructural changes. If some form of policy and/or infrastructural change is introduced, it is possible to change travel patterns and ultimately reduce travel. Here too, ICT could enable changes in travel practices, e.g. through mediated meetings or vehicle sharing. However, for sustainable everyday travel to become widespread, urban planning issues are important. Policy documents and environmental targets can be used proactively to legitimise new policies that enable more sustainable travel practices.

    This thesis shows that everyday practices, in a relatively affluent European urban context, contribute greatly to environmental impacts. Hence, how everyday practices are structured, or could be re-structured, is critical for sustainable development. Practices shape, and are shaped, by their socio-material context. This requires an overall, holistic approach, as offered by practice theory and actor-network theory. A holistic approach is crucial from a sustainability policy perspective, as it enables measures that target some, or all, of the different elements (material, meaning, skills) that constitute practice. It may also be crucial for policies addressing temporal and spatial aspects that structure practices, e.g. societal schedules and people’s homes in relation to their workplace. This presents an opportunity that policymakers could further explore and exploit.

  • 11.
    Thomas, Jean-Baptiste
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Insights on the sustainability of a Swedish seaweed industry2018Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Cultivated seaweed biomass is increasingly perceived as having tremendous potential as a multi-value, environmentally friendly and renewable biomass. Momentum is gathering along the Atlantic coast of Europe and across the world to capitalize on the potential of a more global seaweed industry. In Sweden, these developments have largely been sparked by the Seafarm project and it’s holistic biorefinery approach, which draws on key expertise from five Swedish Universities to lay the foundations for a future seaweed industry. As a part of the project, this thesis principally aimed to effectively assess the sustainability of ongoing developments, most notably through the lenses of viability, environmental life cycle perspectives and potential of a future Swedish seaweed industry. A strategy for assessing sustainability was thus developed with effectiveness in mind and anchored in a broad range of issues highlighted as knowledge gaps by stakeholders; a series of six studies resulted therefrom. Each study contributes insights regarding very specific aspects of the sustainability of a seaweed industry: on the viability of kelp biofuel, threats to viability in the form of potential public aversion to seaweed aquaculture, life cycle perspectives on the cultivation and preservation of seaweed biomass, on the scale and spatial potential of the industry on the West Coast, and finally, on the economic potential of this future industry. This collection of insights contributes six strategic pieces to the vast and dynamic puzzle that is the sustainability of a burgeoning seaweed industry. Together they paint a picture of a viable Swedish seaweed industry with promising potential to contribute positively to key sustainability challenges of the coming decades. 

  • 12.
    Zhang, Wen
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    An add-on filter technique to improve micropollutant removal and water quality in on-site sewage treatment facilities2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Onsite sewage treatment facilities (OSSFs) in Sweden currently release significant amounts of nitrogen (N) and phosphorus (P) into groundwater or/and receiving water bodies. Micropollutants (MPs) have been found in both surface water and groundwater, indicating insufficient removal of MPs by OSSFs. Two laboratory-scale column experiments, followed by a field experiment, were performed to study removal of a set of organic MPs by organic and inorganic sorbents. The set covered different product categories, e.g. an artificial sweetener, organophosphates, parabens, personal care products, perfluoroalkyl substances (PFASs), pesticides, pharmaceuticals, a plasticiser, a polymer impurity, stimulants and surfactants. An experiment using five organic and five inorganic sorbents showed that coal-based organic sorbents performed better than natural fibre and inorganic sorbents in removal of MPs, with 20% higher removal efficiency on average. Five sorbents were selected for a long-term column experiment examining 31 MPs. Physical properties and chemical structure of the sorbents, namely pore structure and surface functional groups, were found to be correlated to their capacity for removal of MPs. Molecular weight, solvent-accessible area, octanol-water partition coefficient and distribution-coefficient of PFASs were found to be strongly positively correlated with their removal by some sorbents. Organic sorbents with good performance in removal of MPs and a conventional sand bed showed limited ability to remove P, while calcium-rich sorbents increased P removal greatly. Two sorbents, granulated activated carbon (GAC) and xyloid lignite (Xylit), were tested for 24 weeks in an add-on filter for effluent from a soil treatment system and found to significantly improve removal of MPs. A replaceable add-on unit for removal of MPs from OSSF effluent is recommended and should contain an organic sorbent such as GAC or Xylit.

  • 13.
    Gu, Zhenhong
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. KTH - SEED.
    An analysis of architectural and urban planning strategies for developing energy efficient cities in China2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis presents a detailed analysis of architecture and urban planning strategies for developingenergy-efficient cities in a Chinese context. The overall aim of the work is to examine how Chineseurbanisation and city construction can be improved from an energy-saving perspective.

    China is in the process of transforming from an agricultural to an industrial country, and it willconsume more energy than ever before. Creating energy-efficient cities is an important part ofsustainable energy development. City development is a complicated process that affects the interestsof many stakeholders, and the strategies for establishing energy-efficient cities can be directed at twolevels: components and systems.

    The main components of energy-efficient cities are energy-efficient buildings, which have been a hottopic in recent years. In China, a number of new, stricter codes for energy-efficient buildings arebeing issued. In addition, many research institutes have developed Building EnvironmentalAssessment (BEA) methods, where energy efficiency is an important factor in the models. Varioustechnical solutions for energy efficiency are also being developed. This thesis analyses differentsolutions and their applicability within the Chinese context.

    The investigation in Nanjing clearly demonstrated that system-level strategies are vital for achievingenergy-efficient cities. The Swedish energy efficient models of the housing development HammarbySjöstad and the smaller scale Eco-villages were analysed to see if these solutions were compatiblewith the Chinese context. The strategies to reduce energy demands can be further subdivided intoreducing building energy consumption and reducing transportation energy consumption. Thesestrategies were implemented into the urban design for the southern region of Hexi New City District,Nanjing, which will be used as an example of new urban construction in a rapidly urbanising China.

    This thesis proposes a route for developing energy-efficient cities. In the construction of Chinesecities, technological strategies for energy-efficient buildings have been implemented successfully, butthe systems structure of such cities requires special attention, particularly in the context of rapidurbanisation. Urban planning with energy considerations must be seen as equally important to thedevelopment of energy-efficient buildings. City planners should play a key role in this process, notby saving energy directly, but indirectly, by influencing the behaviour of persons living, working andtravelling within their city. Local and regional governments, which have special powers in China,should take responsibility for policymaking, demonstration, standardisation and education. In thebroad context of intelligent urban planning, technological, economic, and social strategies for energyefficientbuildings will all play a positive role.

    China’s government has started the process of improving urban energy efficiency. However, thisprocess will be difficult and progress will be slow. The thesis discusses the conditions in the Chinesecontext and identifies problems that require solutions in the near future.

  • 14.
    Nilsson, Anders
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Energy Feedback and Demand Response Strategies: Exploring Household Engagement and Response Using a Mixed Methods Approach2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Real-time energy feedback (EF) and demand response using dynamic pricing tariffs (DR) have been suggested as effective intervention strategies to meet the need for increased energy efficiency and demand flexibility in the residential sector. Although previous studies provide some empirical support for the effectiveness of EF and DR, evaluation approaches used in practical experiments and field trials commonly suffer from several methodological shortcomings, preventing deeper of knowledge on the potential and barriers for EF and DR to influence household energy consumption.

    This thesis explored the potential of employing a mixed methods approach for evaluation of household energy consumption to provide improved understanding on how and why households engage and respond to EF and DR strategies. Three research objectives were set: 1) Analysis of the potential for using high-resolution data from smart meters in evaluation of household energy consumption and response to DR strategies, 2) development of a conceptual framework for evaluation of household responses to EF and DR strategies and analysis of its potential to increase understanding of household responsiveness, and 3) identification and analysis of household motivations, perceptions, and obstacles to engaging in EF and DR strategies.

    The work to achieve these objectives followed a mixed methods research methodology grounded on literature reviews and empirical studies in real-life settings in a single case study, an EF/DR field trial taking place in Stockholm Royal Seaport. A combination of quantitative and qualitative methods was used for data collection and analysis, comprising interviews, surveys, and statistical analysis of smart meter energy data.

    The results suggest that the mixed methods approach addresses several of the limitations and challenges associated with previous evaluation approaches. As regards objective (1), it was found that high-resolution data from smart energy meters can provide evaluation outcomes with increased transparency and accuracy. Regarding objective (2), it was found that the proposed framework can increase understanding of variations in household responsiveness to EF and DR strategies and reveal the relationship between impacts on electricity use and factors influencing energy consumption behavior. As regards objective (3), several obstacles for households to engaging in EF and DR strategies were identified, primarily related to household-individual factors such as knowledge, sense of control, and personal values and attitudes. Based on these findings, key issues and areas for further research are proposed.

  • 15.
    Joyce, Peter James
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Sustainability Assessment and Management.
    Environmental Considerations in the Zero-waste Valorisation of Bauxite Residue: A Life Cycle Perspective2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Bauxite residue, also known as red mud, is produced in large quantities as a result of alumina refining (the first stage in aluminium production), and is one of the world’s most abundant and important industrial wastes. As demand for aluminium continues to increase and space to store this residue diminishes, the potential to utilise bauxite residue as a secondary resource is increasingly being considered by the alumina industry. Bauxite residue can be used as a source of iron, aluminium, titanium oxide, scandium and rare earth oxides, or utilised for its bulk properties to create cement clinkers or inorganic polymers. Achieving any of these uses however requires a series of complex valorisation processes, which in turn require inputs of energy and materials. Some bauxite residues also contain trace amounts of naturally occurring radionuclides.

    The EU Horizon 2020 MSCA-ETN REDMUD project was set up to investigate the valorisation of bauxite residue in an integrated manner. The ultimate aim of the REDMUD project is to develop environmentally-friendly, zero-waste, integrated processes for extracting valuable materials from bauxite residue and/or utilising it at high volume. This thesis presents the environmental perspective on this aim, taking a life cycle view; that is, taking into account the upstream and downstream impacts, in addition to the direct impacts, which may result from diverting bauxite residue from landfill to the proposed valorisation processes. This involves using Life Cycle Assessment (LCA) approaches to understand the environmental balance between the impact avoided through landfill diversion and the substitution of conventional materials, and the impacts incurred by the use of materials and energy in the valorisation processes themselves. Importantly, the potential ionising radiation impact from naturally occurring radionuclides is also considered from a life cycle perspective for the first time.

    A new life cycle impact assessment method for assessing the impacts of naturally occurring radionuclides was developed. In addition, two pieces of research software, designed to overcome the current shortcomings in LCA software with respect to streamlined and prospective LCA studies of emerging technologies are presented as part of this thesis.

    The potential hotspots of environmental impact in a single step valorisation process, the production of high bauxite residue content inorganic polymers, were identified. The results identify the high temperature processing of bauxite residue, in order to transform it into a reactive precursor capable of forming solid inorganic polymers, as a hotspot of environmental impact across a range of environmental impact measures. The production of alkaline activating solutions (the other reagent in the polymerisation reaction) also represented a hotspot of environmental impact. These hotspots were used to identify possible future research directions for this process, which have the potential to reduce the environmental impact of this valorisation process.

    Finally it was shown that even in the absence of a detailed and quantified system description, qualitative approaches based on life cycle thinking can be usefully applied to identify important aspects on both sides of the environmental balance between the impacts avoided and the impacts incurred in waste valorisation. Chemical reaction products, chemical synthesis, thermal and mechanical energy are highlighted as potential sources of environmental impact. A case study, looking at the combined extraction of iron and production of inorganic polymers from bauxite residue was used to demonstrate the validity of these qualitative approaches. This study also demonstrated that combining the extraction of iron and inorganic polymers is vital in order to yield a net environmental benefit in terms of climate change.

    This thesis provides an initial step on the road towards the environmentally sustainable valorisation of bauxite residue, as well as the analytical tools and additional impact assessment measures required to ensure that this journey can be continued, both within the REDMUD project and beyond.

  • 16.
    Fauré, Eléonore
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Strategic Sustainability Studies.
    Sharing the doughnut: Exploring sustainable and just futures2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Despite decades of international discussions or summits on the need to radically reduce e.g. increasing concentrations of greenhouse gases (GHGs) or biodiversity loss, these are still rising. While these negative environmental trends continue, it is important to discuss alternative futures in an attempt to redirect society on a more sustainable and just path.

    The overall aim of the thesis is to develop images of the future and explore what sustainable and just futures might look like. The current environmental impact of Swedish consumption, both in Sweden and abroad, is shown using eight indicators of environmental pressures and resource use – illustrating where in the world the pressures or resource use occur and for which product groups. This gives us a starting point as to where we are today regarding some of the environmental challenges facing Sweden.

    Alternative futures that can challenge existing unsustainable trends are explored using four images of the future – so-called backcasting or long-term transformative scenarios. All of these need to fulfil two environmental and two social sustainability goals and do not rely on continued GDP growth.

    These images represent different strategies to reach the four selected goals.

    Such strategies may however have different consequences not just for these four specific goals but also for other sustainability issues and may have different implications for various groups in society. Therefore, they need to be evaluated accordingly. Existing methods to evaluate future scenarios regarding sustainability aspects are discussed in this thesis as well as the need to develop new methods to encompass all issues.

    A combination of methods and data is used to evaluate what it would actually mean if the scenarios were to fulfil a climate target for Swedish consumption in line with the 1.5°C. trajectory suggested as the target to strive for in the Paris Climate Agreement and in the latest IPCC report (IPCC, 2018) as regards reduction of goods consumption and altered consumption patterns in Sweden.

    This thesis stresses the need to clarify the assumptions made when formulating goals such as whether a perspective on intergenerational (between different generations) and intragenerational justice (within the current generation) is considered. It also underlines the need to identify and discuss potential goal conflicts that necessarily occur when considering several sustainability goals, whether they can be avoided or require potential trade-offs. It highlights the importance of making the underlying values embedded in assessment methods more visible. The intention in revealing goal conflicts, contradictions or hidden values is not to reach consensus but to ensure that the decisions are informed and made in a transparent manner.

    Indeed, these considerations imply moving from a first and rather vague level of meaning of the concept of sustainability where everyone can agree on a definition but no concrete and practical guidance can be gained to a second level where conflicts arise and values differ.

  • 17.
    Holmstedt, Louise
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Evaluation of Sustainable Urban District Developments: The case of Stockholm Royal Seaport2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Urban sustainable development is now seen as one of the keys in the quest for a sustainable world and increased interest in developing sustainable urban districts has become an important feature of urban sustainability. However, if cities and their districts are to be part of this transition, it will be necessary to determine the state and progress of urban developments. Evaluation and follow-up activities must therefore be an integral part of modern sustainability work.

    This thesis investigated evaluation methods and strategies for determining progress towards sustainable urban district development. The Stockholm Royal Seaport district in Sweden was used as the research arena in studies based on urban metabolism theories, including a single case study approach, focus group interviews, the Framework for Strategic Sustainable Development and quantitative data analysis. The thesis main results can be summarised as follows.

    A structured frame for use in theory and practice can strengthen programme development and minimise the risk of built-in problems in environmental and sustainability plans for new urban districts. The proposed evaluation model for Stockholm Royal Seaport displayed strengths regarding core evaluation activities, such as communicating a strong vision and recognising continuity in the evaluation process. It displayed weaknesses as regards organisational structure and system boundaries.

     The proof-of-concept implementation of a Smart Urban Metabolism framework enabled real-time evaluation data on district scale to be generated and processed. The implementation process also led to identification of limitations in the framework, such as access to business sensitive data, failed integration of data streams and privacy concerns. Dynamic, high-resolution meter data can provide a higher degree of transparency in evaluation results and permit inclusion of all stakeholder groups in urban districts. The frequently used energy performance indicator kWh/m2 (Atemp) was shown to be an insufficient communication tool to mediate knowledge, due to conflation of consumption and construction parameters and the need for prior knowledge for full understanding.

  • 18.
    Rasul, Hedi
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering. Koya University.
    Water in roads: Flow paths and pollutant spread2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    For better road construction and maintenance while minimising damage to the environment and groundwater, it is essential to monitor and model hydrological impacts on roads and consider pollution of groundwater. Water content in unbound material in road layers changes continuously and water flow usually occurs along pathways that are the main corridors for pollutant spread to groundwater. Good awareness of hydrological conditions and of water and solute transport in road layers down to the groundwater can be helpful in minimising environmental impacts during construction and operation. Today, road planning is usually carried out without specifically considering hydrological criteria. To improve understanding of the links between water in roads and groundwater, this thesis developed investigation methods and used numerical simulations for estimating seasonal variations, flow pathways and pollutant spread.

    Seasonal changes in road water content in an operational road, tracer tests pathways from the road shoulder and percolation down to groundwater were monitored non-destructively using electrical resistivity tomography (ERT). Chloride concentration changes were estimated based on ERT data inversion. New monitoring methodology was assessed and data analysis was performed on ERT data from different road zones and layers, which were analysed statistically and correlated to precipitation, temperature and ground moisture content. Data were collected at a unique road test station on a motorway north-west of Stockholm and in tracer experiments on typical roads in southern and central Sweden. Two-dimensional (2D) models of heat and moisture changes were prepared for a road section, considering vapour pressure and frozen water content changes using partial differential equations (PDE). Model parameters were optimised based on soil moisture and temperature data from the E18 road test station. A PDE model was used for calculating liquid water and ice content changes in different scenarios based on geometry and design changes. Both pathways and travel times were traced by 2D and pseudo 3D inverse modelling of the ERT measurements.

    The field data revealed clear preferential pathways of moisture and salt in the road shoulders that varied significantly during different seasons. Most infiltration occurred directly into the road shoulder, but entered the road embankment with higher percolation speed in modern roads than in old roads consisting of natural soils. The simulations showed that seasonal climate changes and the upper boundary condition were key factors determining water content in different road layers. These findings advance understanding of water in roads and represent a step towards more sustainable and environmental friendly road construction and maintenance. In addition the research results give lessons for practice both regarding monitoring and road construction. For monitoring it provides a new method in data collection and analysis. For construction and maintenance, mitigation measures are suggested, which comprise a tight road shoulder, by e.g. adding a fine grained layer on the shoulder or covering with vegetation.

  • 19.
    Pang, Xi
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Sustainability Assessment and Management.
    Trade-off analysis of forest ecosystem services – A modelling approach2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Forest is a resource that is increasingly utilized for multiple purposes. The balance between energy demands and the long-term capacity of ecosystems to support biodiversity and other ecosystem services is crucial. The aim of this project was to increase the knowledge on and to develop methods and tools for trade-offs and synergies analysis among forest ecosystem services based on different forest management policies.

    Paper I provides an overview of existing models for integrated energy-environment assessment. A literature review was conducted on assessment models and their ability to integrate energy with environmental aspects. Missing environmental aspects concern land use, landscapes and biodiversity. In Paper II a modelling framework was set up to link a landscape simulator with a habitat network model for integrated assessment of bioenergy feedstock and biodiversity related impacts in Kronoberg County. In Paper III we continued with the same management scenarios, while the analysis was expanded to five ecosystem services by developing the Landscape simulation and Ecological Assessment (LEcA) tool: industrial wood, bioenergy, forest carbon stock, recreation areas and habitat networks. In Paper IV we present two heuristic methods for spatial optimization – simulated annealing (SA) and genetic algorithm (GA) – to find optimal solutions for allocating harvest activities, in order to minimize the impacts on habitat networks. In Paper V, as response to the findings in Paper I, we linked the energy model MESSAGE with our LEcA tool for forest bioenergy demand assessment while applying environmental and transport restrictions, in a study of Lithuania.

    We found trade-offs between industrial wood production and bioenergy on one side, and recreation values, biodiversity, and to some extent carbon storage on the other side. The LEcA tool integrated forest simulation and management with assessment of ecosystem services, which is promising for integrated sustainability assessment of forest management policies.

  • 20.
    Zuo, Minyu
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Enhanced phosphorus removal from wastewater using virgin and modified slags: performance, speciation and mechanisms2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Argon oxygen decarburization slag (AOD) was tested in batch and column experiments to investigate its phosphorus (P) removal performance. The effects of factors such as AOD dose, initial P concentration of the feeding solution, and aging on the P removal ability of the slags were analyzed. In a column experiment, electric arc furnace slag (EAF), blast furnace slag (BFS) and AOD were combined in five different ways to determine optimal conditions for P removal. In another column experiment, the three types of slag were modified with polyethylene glycol (PEG) and NaOH to adjust their dissolution properties and the effect on P removal performance was examined. In the batch experiments, AOD exhibited very promising P removal ability. It removed 94.8% of P from 6.5 mg P L-1 synthetic solution in 4 hours with a dose of 5 g L-1. Maximum P removal capacity of 27.5 mg P g-1 was achieved. In the dual-filter column experiment, the column packed with only EAF had the best P removal performance (consistently above 93%). Amorphous calcium phosphate (ACP) was identified as the main P species in the five slag samples collected from the outlet chambers. The contributions from crystalline calcium phosphate (Ca-P) and P adsorbed on iron/aluminum (hydr)oxides were greater in samples from the inlet chambers. The P speciation results revealed that P was predominantly removed by the slags through formation of ACP. The second column experiment showed that modification with PEG and NaOH solution only enhanced short-term P removal by the slags. However, exhaustion of the modified slags occurred much earlier, indicating that the modification process had shortened the lifespan of the slags. Untreated AOD showed better P removal than untreated EAF until pore volume 244, probably due to faster dissolution rate of gamma dicalcium silicate (dominating in AOD according to the XRD results) than of beta dicalcium silicate (dominating in EAF).

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