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  • 251. Mpagi, K. H.
    et al.
    Rose, K.
    Plaza, Elzbieta
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Use of volcanic ash and its impact on algae proliferation in drinking water filtration2013In: Journal of Water Sanitation and Hygiene for Development, ISSN 2043-9083, Vol. 3, no 2, p. 199-206Article in journal (Refereed)
    Abstract [en]

    With increasing pollution of the available water resources, development of safe drinking water supplies is increasingly becoming a challenge, both for developing and developed countries. To alleviate the prevailing difficulties, approaches should focus on sustainable water supply and treatment systems that require minimal maintenance and operator skills. In this study, a pre-treatment of water containing algae using a combination of volcanic ash (VA) and sand in a filtration system was assessed. The results indicated that a combination of VA and sand performed better in the removal of algae than sand alone. However, it was noted that different algae genera were removed at different rates within the two types of media arrangement. In addition, there was an increase in the filtration run length of the ash-sand columns with VA on top of sand of about two and half times compared with the sand columns. It is therefore anticipated that pre-treatment of raw water laden with algae using ash-sand would probably improve on the performance of the subsequent conventional processes in removing intact cells of algae and thus reduce the threat of releasing toxins into the water that may not be removed by the subsequent conventional treatment processes.

  • 252.
    Mukherjee, A.
    et al.
    IIT, Dept Geol & Geophys, Kharagpur, W Bengal, India..
    Fryar, A. E.
    Univ Kentucky, Dept Earth & Environm Sci, Lexington, KY USA..
    Scanlon, B. R.
    Univ Texas Austin, Bur Econ Geol, Jackson Sch Geosci, Austin, TX USA..
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Bhattacharya, A.
    Govt West Bengal, Publ Hlth Engn Directorate, Kolkata, India..
    Wide spread arsenic in deeper groundwater of western Bengal basin, West Bengal, India: Implications for sustainable alternate drinking water sources2012In: UNDERSTANDING THE GEOLOGICAL AND MEDICAL INTERFACE OF ARSENIC, AS 2012 / [ed] Ng, JC Noller, BN Naidu, R Bundschuh, J Bhattacharya, P, CRC PRESS-TAYLOR & FRANCIS GROUP , 2012, p. 522-525Conference paper (Refereed)
    Abstract [en]

    Availability of safe drinking water is a major concern in the delta plains of the major Himalayan-Tibetan rivers in southern and southeastern Asia. While indiscriminate use of rivers and other surface water bodies for disposal of sewage and industrial waste has rendered them non-potable, natural, non-point source, elevated Arsenic (As) concentrations in groundwater exceeding the World Health Organization's (WHO) guideline value for drinking water of 0.01 mg/L have put millions of people at risk. Hence, finding an alternate, suitable and sustainable drinking-water source has been a priority in these areas. Generally, higher concentrations of dissolved As are found in groundwater of shallower aquifers and several studies have advocated deeper aquifers as a possible safe substitute. Using a composite hydrogeological approach, we demonstrate that regional-scale deeper groundwater As contamination in the western Bengal basin is dependent on the aquifer-aquitard framework and complex redox processes with partial equilibrium under natural flow conditions. Widespread deep irrigation pumping may be drawing shallower, contaminated groundwater down to greater depths. These findings have severe implications on finding alternate drinking water sources, in West Bengal, and adjoining areas of Bangladesh, with plausible similar geological and hydrogeological framework.

  • 253.
    Mushi, Catherine
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Urban Water Management in Dar es Salaam: A case for an Integrated Approach.2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The main objective of this study was to determine water access and use characteristics of household in Dar es Salaam in order to determine how the integrated urban water management (IUWM) approach can be applied in solving the water crisis in the city as well as other challenges of urban water supply and sanitation.

    A limited household water access and use survey was carried out in all three districts of Dar es Salaam.

    It was found that some of the principles of IUWM such “fit for purpose use” are already being practiced informally at household level, although this is not recognized in planning by Water Authorities. The study also shows that practices geared at saving and efficient use of water are well entrenched in households; with even those with access to sufficient amounts of water practicing it. At the user level, there do not appear to be any obstacles to adoption of IUWM.

    The potential for IUWM application is therefore shown to exist and recommendations are made for immediate measures such as incorporation of the various water sources in use in households into the formal system as well as improvements to methods of water saving, ground water extraction and rain water harvesting. Recommendations are also provided for wider adaptation of the entire city water management system to IUWM with emphasis on context driven solutions.

  • 254. Mushtaq, S.
    et al.
    Maraseni, T. N.
    Reardon-Smith, K.
    Bundschuh, Jochen
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. Univ So Queensland, Australia.
    Jackson, T.
    Integrated assessment of water-energy-GHG emissions tradeoffs in an irrigated lucerne production system in eastern Australia2015In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 103, p. 491-498Article in journal (Refereed)
    Abstract [en]

    Robust understanding of possible trade-offs and synergies between climate change, energy and water sector policies is critical to achieving economically viable and environmentally sound agricultural production systems in a low-carbon water-constrained economy, in which greenhouse gas (GHG) emissions are penalized and water savings rewarded. Accurate assessment of the potential costs/benefits of investment decisions can help to optimize the economic efficiency of agricultural production while minimizing environmental impacts. This paper presents a novel integrated framework, based on carbon and water accounting, which enables analysis of potential trade-offs between water savings, energy consumption, GHG emissions and economic costs/benefits associated with the adoption of new water efficient irrigation technologies. The framework was applied to an irrigated lucerne cropping system in eastern Australia and compares the costs/benefits of old roll-line sprinkler irrigation systems against new pressurized systems. Positive synergies were found with the adoption of the new technology, which saved both water and energy use, reduced total GHG emissions and resulted in net economic returns across a range of carbon prices. The results of this study provide support for an integrated evidence-based approach to policy development and strategic decision-making and for the prioritization of investments on both economic and environmental grounds.

  • 255.
    Mörtberg, Ulla
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Biodiversity, ecosystem services and renewable energy options2013Conference paper (Other academic)
  • 256.
    Mörtberg, Ulla
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Energy systems and environmental assessment: the sustainability of renewables2013Conference paper (Other academic)
  • 257.
    Mörtberg, Ulla
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Methods for environmental assessment of wind power policy and plans2013Conference paper (Other academic)
  • 258.
    Mörtberg, Ulla
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Babelon, Ian
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Malmgren, Stella
    Holmstedt, Cecilia
    Wind power planning in Sweden: The treatment ofbiodiversity and ecosystem services2015In: Conference on Wind Energy and Wildlife Impacts, 10-12 March in Berlin, Germany / [ed] Köppel, J. & Schuster, E., Technische Universität Berlin , 2015, p. 49-Conference paper (Refereed)
  • 259.
    Mörtberg, Ulla
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Balfors, Berit
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Landskapsekologisk planering i och kring tätorter [Landscape ecological planning in and around urban areas, in Swedish]2003In: Vilda djur i stadsmiljö - Tillgång eller problem? / [ed] Bo Carlestål, Stockholm: Kungl. Skogs- och Lantbruksakademien , 2003, Vol. 142, p. 13-17Conference paper (Refereed)
  • 260.
    Mörtberg, Ulla
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    de Strasser, Lucia
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Howells, Mark
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Gordon, Sara
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Assessing the energy-water-land use nexus2015Conference paper (Refereed)
    Abstract [en]

    System models addressing the nexus of energy, water and land use in transboundary watersheds. Issues of stakeholder involvement as well as integration of ecosystem aspects in nexus assessments are discussed.

  • 261.
    Mörtberg, Ulla
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Deal, Brian
    Cvetkovic, Vladimir
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Balfors, Berit
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Azcarate, Juan
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Haas, Jan
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geoinformatics.
    Pang, Xi
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Integrating ecosystem services in urban energy trajectories2015Conference paper (Refereed)
  • 262.
    Mörtberg, Ulla
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Goldenberg, Romain
    Kalantari, Zahra
    Stockholms Universitet.
    Kordas, Olga
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Deal, Brian
    University of Illinois Urbana Champaign.
    Balfors, Berit
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Cvetkovic, Vladimir
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Integrating ecosystem services in the assessment of urban energy trajectories: A study of the Stockholm Region2017In: Energy Policy, ISSN 0301-4215, E-ISSN 1873-6777, Vol. 100, p. 338-349Article in journal (Refereed)
    Abstract [en]

    Urban development trajectories are changing towards compact, energy-efficient cities and renewable energy sources, and this will strongly affect ecosystem services (ES) that cities are dependent on but tend to disregard. Such ES can be provisioning, regulating and cultural ES, around which competition over land resources will increase with energy system shifts. Much of this can be foreseen to take place within urbanising regions that are simultaneously the living environment of a major part of the human population today. In order to inform critical urban policy decisions, tools for integrated assessment of urban energy and transport options and ecosystem services need to be developed. For this purpose, a case study of the Stockholm region was conducted, analysing three scenarios for the future urbanisation of the region, integrating a transport energy perspective and an ES perspective. The results showed that a dense but polycentric development pattern gives more opportunities for sustainable urban development, while the dense monocentric scenario has apparent drawbacks from an ES perspective. The methodology is compatible with a model integration platform for urban policy support and will thus enable integrated policy assessment of complex urban systems, with the goal of increasing their sustainability.

  • 263.
    Mörtberg, Ulla
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Goldenberg, Romain
    Kalantari, Zahra
    Kordas, Olga
    Deal, Brian
    Balfors, Berit
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Cvetkovic, Vladimir
    Integrating ecosystem services in urban compaction trajectories - A study of the Stockholm Region2016Conference paper (Refereed)
  • 264.
    Mörtberg, Ulla
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Haas, Jan
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Geoinformatics.
    Zetterberg, Andreas
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Franklin, Joel
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport and Location Analysis.
    Jonsson, Daniel
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport and Location Analysis.
    Deal, Brian
    University of Illinois at Urbana-Champaign.
    Urban ecosystems and sustainable urban development-analysing and assessing interacting systems in the Stockholm region2013In: Urban Ecosystems, ISSN 1083-8155, E-ISSN 1573-1642, Vol. 16, no 4, p. 763-782Article in journal (Refereed)
    Abstract [en]

    In order to build competence for sustainability analysis and assessment of urban systems, it is seen as essential to build on models representing urban form, landuse and transportation, urban metabolism, as well as ecological processes. This type of analysis of interacting sub-systems requires an advanced model integration platform, yet open for learning and for further development. Moreover, since the aim is to increase urban experience with ecosystem management in the wide sense, the platform needs to be open and easily available, with high visualisation capacity. For this purpose, the LEAM model was applied to the Stockholm Region and two potential future scenarios were developed, resulting from alternative policies. The scenarios differed widely and the dense urban development of Scenario Compact could be visualised, destroying much of the Greenstructure of Stockholm, while Scenario Urban Nature steered the development more to outer suburbs and some sprawl. For demonstration of the need for further development of biodiversity assessment models, a network model tied to a prioritised ecological profile was applied and altered by the scenarios. It could be shown that the Greenstructure did not support this profile very well. Thus, there is a need for dynamic models for negotiations, finding alternative solutions and interacting with other models. The LEAM Stockholm case study is planned to be further developed, to interact with more advanced transport and land use models, as well as analysing energy systems and urban water issues. This will enable integrated sustainability analysis and assessment of complex urban systems, for integration in the planning process in Stockholm as well as for comparative sustainability studies between different cities, with the goal to build more sustainable urban systems and to increase urban experiences in ecosystem management.

  • 265. Neidhardt, H.
    et al.
    Berner, Z. A.
    Freikowski, D.
    Biswas, Ashis
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Majumder, S.
    Winter, J.
    Gallert, C.
    Chatterjee, D.
    Norra, S.
    Organic carbon induced mobilization of iron and manganese in a West Bengal aquifer and the muted response of groundwater arsenic concentrations2014In: Chemical Geology, ISSN 0009-2541, E-ISSN 1872-6836, Vol. 367, p. 51-62Article in journal (Refereed)
    Abstract [en]

    The exact circumstances that cause the widespread enrichment of Mn and As in groundwater of the Bengal Delta Plain (BDP) and many other Asian delta areas still remain a matter of debate in the scientific community. We conducted an in situ field experiment in the central BDP region to investigate the influence of organic matter on the mobility of Fe, Mn and As in shallow aquifers. The groundwater at our study site was initially characterized by a circum-neutral pH, low concentrations of O2, NO3 - and SO4 2-, and increased Fe, Mn and As concentrations, reflecting reducing conditions in the aquifer. Since organic matter controls microbially mediated redox processes which are believed to result in the mobilization of Fe, Mn and As from Holocene aquifer sediments, an easily degradable carbon source (sucrose) was introduced into a shallow aquifer via four nested monitoring wells and distributed by circular pumping. Initial sucrose concentrations reached up to 2.55mM in the local groundwater and induced a strong increase in the activity of indigenous microbes that decomposed the sucrose within the following 14days stepwise into intermediate catabolic products (e.g., acetic acid), and finally to CO2/HCO3 -. The formation of organic acids was accompanied by a temporary decline in the pH and the redox potential, as well as an increase in the concentration of most major and trace elements in the groundwater by several times. While Mn concentrations rose up to 81.3μM (representing a 7.5 fold increase), Fe (on average 96.7% Fe(II)) concentrations reached a considerable transient maximum of 1390μM, which was 36 times higher than the initial baseline value. The most significant observation of this experiment is that the relative increments of dissolved As (on average 95.8% As(III)) reached between 19 and 49% only, which is in clear contrast to the pronounced mobilization of Fe, Mn and other trace elements. Changes in the groundwater composition during the experiment imply that the mobilization of Fe and Mn was primarily caused by a reductive dissolution of Mn-oxides and Fe-(oxyhydr)oxides, resulting from the stimulation of indigenous bacteria by the addition sucrose. In this context, the release of As can be attributed to the dissolution of Fe-(oxyhydr)oxides, which constitute the principal source of As in the aquifer sediments according to mineralogical and geochemical analyses. In contrast to the pronounced mobilization of Fe, the response of groundwater arsenic concentrations appeared to be muted, as indicated by subsequently declining As to Fe mol ratios that dropped one order in magnitude. The remarkable decoupling of As from Fe mobilization indicates that the aquifer sediments were apparently capable of compensating for the additional release of As. We attribute this As buffer potential to remaining Fe-minerals and potentially newly formed Fe(II)- and mixed Fe(II/III)-mineral phases, which were able to readily immobilize dissolved As. Sequential extraction results of the initial aquifer sediments further support this interpretation, revealing that up to 85% of the total As in the sediments was already present in adsorbed form, with Fe-minerals as principal hosts. Hence, the experimental data implies that a biogeochemically controlled environment of competing As release and retention arose after the addition of sucrose, where Fe-mineral phases played a key role in buffering the release of As. We further conclude that organic carbon limited aquifer systems in the BDP with increased As concentrations in groundwater may exhibit an unexpected buffer potential towards an additional As release, even when vast amounts of easily degradable organic carbon are introduced into the system.

  • 266. Neidhardt, H.
    et al.
    Berner, Z.
    Freikowski, D.
    Biswas, Ashis
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Winter, J.
    Chatterjee, D.
    Norra, S.
    Influences of groundwater extraction on the distribution of dissolved As in shallow aquifers of West Bengal, India2013In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 262, p. 941-950Article in journal (Refereed)
    Abstract [en]

    Here we report temporal changes of As concentrations in shallow groundwater of the Bengal Delta Plain (BDP). Observed fluctuations are primarily induced by seasonally occurring groundwater movement, but can also be connected to anthropogenic groundwater extraction. Between December 2009 and July 2010, pronounced variations in the groundwater hydrochemistry were recorded in groundwater samples of a shallow monitoring well tapping the aquifer in 22-25m depth, where Astot concentrations increased within weeks from 100 to 315μgL-1. These trends are attributed to a vertically shift of the hydrochemically stratified water column at the beginning of the monsoon season. This naturally occurring effect can be additionally superimposed by groundwater extraction, as demonstrated on a local scale by an in situ experiment simulating extensive groundwater withdrawal during the dry post-monsoon season. Results of this experiment suggest that groundwater extraction promoted an enduring change within the distribution of dissolved As in the local aquifer. Presented outcomes contribute to the discussion of anthropogenic pumping influences that endanger the limited and yet arsenic-free groundwater resources of the BDP.

  • 267.
    Nguyen, Nga
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Multivariate analysis and GIS in generating vulnerability map of acid sulfate soils.2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The study employed multi-variate methods to generate vulnerability maps for acid sulfate soils (AS) in the Norrbotten county of Sweden. In this study, the relationships between the reclassified datasets and each biogeochemical element was carefully evaluated with ANOVA Kruskal Wallis and PLS analysis. The sta-tistical results of ANOVA Kruskall-Wallis provided us a useful knowledge of the relationships of the preliminary vulnerability ranks in the classified datasets ver-sus the amount of each biogeochemical element. Then, the statistical knowledge and expert knowledge were used to generate the final vulnerability ranks of AS soils in the classified datasets which were the input independent variables in PLS analyses. The results of Kruskal-Wallis one way ANOVA and PLS analyses showed a strong correlation of the higher levels total Cu2+, Ni2+ and S to the higher vulnerability ranks in the classified datasets. Hence, total Cu2+, Ni2+ and S were chosen as the dependent variables for further PLS analyses. In particular, the Variable Importance in the Projection (VIP) value of each classified dataset was standardized to generate its weight. Vulnerability map of AS soil was a result of a lineal combination of the standardized values in the classified dataset and its weight. Seven weight sets were formed from either uni-variate or multi-variate PLS analyses. Accuracy tests were done by testing the classification of measured pH values of 74 soil profiles with different vulnerability maps and evaluating the areas that were not the AS soil within the groups of medium to high AS soil probability in the land-cover and soil-type datasets. In comparison to the other weight sets, the weight set of multi-variate PLS analysis of the matrix of total Ni2+& S or total Cu2+& S had the robust predictive performance. Sensitivity anal-ysis was done in the weight set of total Ni2+& S, and the results of sensitivity analyses showed that the availability of ditches, and the change in the terrain sur-faces, the altitude level, and the slope had a high influence to the vulnerability map of AS soils. The study showed that using multivariate analysis was a very good approach methodology for predicting the probability of acid sulfate soil.

  • 268.
    Nickman, Alireza
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. KTH/ The Royal Institute of Technology.
    Modeling moisture and temperature dynamics in road structure during winter conditionsManuscript (preprint) (Other academic)
    Abstract [en]

    Excess moisture significantly impact durability and sustainability of road components especially in cold regions. To improve understanding of moisture dynamics in roads with drainage system, hourly measured moisture content, soil temperature and groundwater level data during a 3-year period from a test site in Växjö, Sothern Sweden were utilized. Seasonal and manipulated changes in the groundwater level and moisture dynamics were observed that describe extreme conditions providing extra moisture to the upper layers of road. CoupModel was used to estimate mass and heat balance in four depths of two spots of the road section. Good performances of the model were achieved in calculation of the soil moisture in different depths. Soil water retention curve parameters were sensitive to constrain criteria which demonstrate importance of soil texture in controlling moisture dynamics. Model could properly capture temperature dynamic during winter time but simulated excess evaporation from soil layers reduced performance of model in the estimation of temperature during summer The combined monitoring and modelling of physical conditions in the road structure will be highly relevant to help decision makers and road engineers to avoid moisture in road structures and to also identify crucial events from meteorological data.

  • 269.
    Nickman, Alireza
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Predicting locations sensitive to flash flooding along forest roads considering physical catchment descriptors2013In: Comprehensive Flood Risk Management: Research for Policy and Practice, Taylor & Francis Group, London, 2013, p. 215-222Conference paper (Refereed)
    Abstract [en]

    Roads influence the hydrologic response of a watershed as they affect the water regime.This is important especially during extreme precipitation events in critical spots of roads and watersheds.This study suggests a method to analyze watershed characteristics and road descriptors, so-called PhysicalCatchment Descriptors (PCDs), for prediction of flood risk along roads. The method was developed andtested in a Geographical Information System using topographical, geological and road data from an areain W Sweden having experienced severe road flooding during an intensive rain event.The results show that there are two categories of intrinsic descriptors which are useful for prediction of criticalspots prone to flooding along roads in a watershed: (a) watershed-related descriptors and (b) road-relateddescriptors. Analysis of superimposed combinations of these two categories of descriptors can be used foridentification and pre-evaluation of critical spots with high risk of flooding in watersheds containing roads.

  • 270.
    Nickman, Alireza
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. KTH/ The Royal Institute of Technology.
    Road disasters? Modeling and assessment of Swedish roads within crucial climate conditions2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    An efficient maintenance of roads to ensure high accessibility and durability of the transport capacity requires an understanding of how the hydrological response depends on both the road and the landscape characteristics. New methods and data were used to identify and explain interaction between roads and surrounding environment and their influence on hydrologic responses both in watershed scale and road-section scale. In the watershed scale, flood hazard probability was made with reference to the most influential physical catchment descriptors and road characteristics. Additionally, a physical based model was used to estimate the effect of road topography on the hydrological responses of 20 watersheds to storms with different intensities. A simple method was developed and discussed to address flood risk probability in the road-stream crossings concerning the correlation between the quantities of the physical catchment descriptors and occurrence/absence of flooding. The most influential factors in describing the probability of flooding along the roads were topographic wetness index, soil properties, road density and channel slopes. A detailed study of simulated flow duration curves showed differences between the 20 watersheds for three different storms based on topography with and without roads. An increase in peak flow and reduced time to pick occurred with existence of roads and increased storm intensity.In the road-section scale, an uncertainty-based simulation approach was used to identify the most influencing processes in controlling the dynamics of the groundwater level. A model (CoupModel) set up with four different geological stratifications was made to model two positions in a slope upstream of a road with drainage pipes and ditches. Results from the simulations indicate the significance of precipitation rate, road drainage and position in hillslope, and soil properties and stratifications in controlling groundwater levels. The same model was also applied to simulate soil moisture and temperature dynamics in two road sections by using groundwater and climate data. Porous media properties were obtained as statistical distribution function that provided the best performance of moisture and temperature dynamic in the road layers and underlying soil.

  • 271.
    Nickman, Alireza
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    The role of roads on hydrological response: Modeling and assessment for Swedish watersheds2014Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Understanding the role of road networks in alteration of hydrological responses is crucial for maintaining the accessibility and durability of road infrastructures. Road construction is one of the most common man made disturbances to a landscape. However, still the quantitative role of road topographical and geo-morphological properties on the hydrological response

    of storms in catchments is only partially understood. The aim of this study was to use new methods to estimate and quantify the flood hazard probability with reference to the most influential physical catchment descriptors and road characteristics. In addition physical based modelling was used to estimate the effect of road topography on the hydrological responses of watersheds to storms with different intensities. A simple method was developed and discussed to address the most susceptible locations to flooding along the roads. Multivariate statistical analysis (PLS) employed to quantify the flood risk probability in the road-stream crossings concerning the correlation between the quantities of the physical catchment descriptors and occurrence/absence of flooding. The most influential factors in describing the probability of flooding along the roads were topographic wetness index, soil properties, road density and channel slopes. A detailed study of simulated flow duration curves showed differences between 20 watersheds for three different storms based on a digital elevation data with and without roads. An increase in peak flow and reduced delay occurred with increased storm intensity. However, the impact of the roads was much smaller and only possible to identify by detailed examination of statistical descriptors.

  • 272.
    Nickman, Alireza
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. KTH/ The Royal Institute of Technology.
    Uncertainty based approach to simulate groundwater levels in a hillslope upstream of a roadManuscript (preprint) (Other academic)
    Abstract [en]

    Knowledge of the processes governing groundwater dynamics in the areas close to roads is important for sustainable road infrastructure in the face of a changing climate. This study established an uncertainty based approach to simulate groundwater oscillations in a hillslope upstream of a road by using a process based model. Four different soil configurations were analyzed in CoupModel to simulate groundwater dynamics in presence of a road drainage system by implementation of meteorological data as driving factors. An approach similar to GLUE method was applied to analyze the statistical performance of the simulated groundwater level versus high resolution measured groundwater level dynamics. Results of the simulations indicate deviations in simulated results due to different soil stratifications. Uncertainties resulted from the lack of precise information about the geological structure of the site are important contributors to deviated simulation results. Different scenarios showed different model performances in which a simpler soil profile describes better the groundwater dynamics when it is closer to the road drainage system while a more complicated soil profile better describes groundwater dynamics in undisturbed soils. Correlation between hydraulic conductivity of each layer and the model performance was discussed. The results also indicate significance of variables such as physical drainage characteristics of the road in governing level of saturations also the position of the road structure in a hillslope. Texture (hydraulic conductivity) of the soil layers that fluctuation of groundwater occurs in those layers and types of modifications that have been done due to road construction are important driving factors. These factors are suggested as suitable indicators for designing an early warning system based on physical characteristics of a road site.

  • 273.
    Nickman, Alireza
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. KTH/ The Royal Institute of Technology.
    Uncertainty based approach to simulate groundwater levels in a hillslope upstream of a roadManuscript (preprint) (Other academic)
    Abstract [en]

    Knowledge of the processes governing groundwater dynamics in the areas close to roads is important for sustainable road infrastructure in the face of a changing climate. This study established an uncertainty based approach to simulate groundwater oscillations in a hillslope upstream of a road by using a process based model. Four different soil configurations were analyzed in CoupModel to simulate groundwater dynamics in presence of a road drainage system by implementation of meteorological data as driving factors. An approach similar to GLUE method was applied to analyze the statistical performance of the simulated groundwater level versus high resolution measured groundwater level dynamics. Results of the simulations indicate deviations in simulated results due to different soil stratifications. Uncertainties resulted from the lack of precise information about the geological structure of the site are important contributors to deviated simulation results. Different scenarios showed different model performances in which a simpler soil profile describes better the groundwater dynamics when it is closer to the road drainage system while a more complicated soil profile better describes groundwater dynamics in undisturbed soils. Correlation between hydraulic conductivity of each layer and the model performance was discussed. The results also indicate significance of variables such as physical drainage characteristics of the road in governing level of saturations also the position of the road structure in a hillslope. Texture (hydraulic conductivity) of the soil layers that fluctuation of groundwater occurs in those layers and types of modifications that have been done due to road construction are important driving factors. These factors are suggested as suitable indicators for designing an early warning system based on physical characteristics of a road site.

  • 274.
    Nickman, Alireza
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Jansson, Per-Erik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Lyon, Steve W.
    Olofsson, Bo
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Kalantari, Zahra
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    The impact of roads on hydrological responses: A case study in SwedenManuscript (preprint) (Other academic)
    Abstract [en]

    A method engaged for simulating and assessing the alterations excreted by road topography within watersheds and estimating the road effects on hydrologic responses. The method uses Geographic Information System (GIS) to allocate and eliminate roads from the elevation data. HEC-HMS was used to model surface and near surface hydrological responses of watersheds with roads and without roads in response to three storms with different intensities. A detailed study of the simulated flow duration curves showed differences between 20 watersheds for three different storms based on a digital elevation data with and without roads. To compare flow duration curves, L-moment ratios were calculated and their variation compared. An increase in peak flow and reduced delay occurred with increased storm intensity. Variations of the L-moment ratios were larger in larger watersheds. However, the impact of the roads was much smaller and only possible to identify by detailed examination of statistical descriptors. The results are useful to gain a better estimating of the effect of road topography in hydrological processes and responses especially in high storm intensities.

  • 275.
    Nickman, Alireza
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Lyon, Steve W.
    Jansson, Per-Erik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Olofsson, Bo
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Simulating the impact of roads on hydrological responses: examples from Swedish terrain2016In: Hydrology Research, ISSN 1998-9563, Vol. 47, no 4, p. 767-781Article in journal (Refereed)
    Abstract [en]

    In this study, the potential impacts of road topography on hydrologic responses at the watershed scale were simulated. The method considered used a geographic information system to identify road embankment locations and subsequently remove them from the baseline elevation data. Starting from both the 'with' and 'without' road elevation model, the surface and near-surface hydrological responses for 20 watersheds in Sweden were modeled in HEC-HMS under three different storm intensities. Flow duration curves (FDCs) were used to compare hydrologic responses for the different modeling scenarios under the various storm intensities. Specifically, L-moment ratios of the FDCs were calculated and their variation compared. Results showed an increase in peak flow amounts and reduction in time to peak with increased storm intensity. In addition, variations of the L-moment ratios were larger in larger watersheds. However, the impact of the roads on the modeled hydrologic responses was much smaller than anticipated and only identifiable through detailed examination of the L-moment statistical descriptors. Our findings not only highlight the potential impacts of road topography on watershed-scale hydrology (especially concerning high intensity storms) but also provide a methodology for detecting the even rather small changes that could manifest, for example, under coupled road network and climatic changes.

  • 276. Nilon, Charles
    et al.
    Aronson, Myla
    Goddard, M A
    LaSorte, F A
    Katti, M
    Lepczyk, C A
    MacGregor-Fors, I
    Warren, P S
    Hedblom, Marcus
    Louwe Kooijmans, Jip
    Mörtberg, Ulla
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Cities as hotspots for bird conservation2013Conference paper (Refereed)
  • 277.
    Nilsson, Charlotte
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Lakshmanan, Ramnath
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Renman, Gunno
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Kuttuva Rajarao, Gunaratna
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Efficacy of reactive mineral-based sorbents for phosphate, bacteria, nitrogen and TOC removal - Column experiment in recirculation batch mode2013In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 47, no 14, p. 5165-5175Article in journal (Refereed)
    Abstract [en]

    Two mineral-based materials (Polonite and Sorbulite) intended for filter wells in on-site wastewater treatment were compared in terms of removal of phosphate (PO4-P), total inorganic nitrogen (TIN), total organic carbon (TOC) and faecal indicator bacteria (Escherichia coli and Enterococci). Using an innovative, recirculating system, septic tank effluent was pumped at a hydraulic loading rate of 3000 L m(2) d(-1) into triplicate bench-scale columns of each material over a 90-day period. The results showed that Polonite performed better with respect to removal of PO4-P, retaining on average 80% compared with 75% in Sorbulite. This difference was attributed to higher CaO content in Polonite and its faster dissolution. Polonite also performed better in terms of removal of bacteria because of its higher pH value. The total average reduction in E. coli was 60% in Polonite and 45% in Sorbulite, while for Enterococci the corresponding value was 56% in Polonite and 34% in Sorbulite. Sorbulite removed TIN more effectively, with a removal rate of 23%, while Polonite removed 11% of TIN, as well as TOC. Organic matter (measured as TOC) was accumulated in the filter materials but was also released periodically. The results showed that Sorbulite could meet the demand in removing phosphate and nitrogen with reduced microbial release from the wastewater treatment process.

  • 278.
    Nilsson, Charlotte
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Renman, Gunno
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Johansson Westholm, Lena
    Renman, Agnieszka
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Drizo, Aleksandra
    Effect of organic load on phosphorus and bacteria removal from wastewater using alkaline filter materials2013In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 47, no 16, p. 6289-6297Article in journal (Refereed)
    Abstract [en]

    The organic matter released from septic tanks can disturb the subsequent step in on-site wastewater treatment such as the innovative filters for phosphorus removal. This study investigated the effect of organic load on phosphorus (P) and bacteria removal by reactive filter materials under real-life treatment conditions. Two long-term column experiments were conducted at very short hydraulic residence times (average similar to 5.5 h), using wastewater with high (mean similar to 120 mg L-1) and low (mean similar to 20 mg L-1) BOD7 values. Two alkaline filter materials, the calcium-silicate material Polonite and blast furnace slag (BFS), were tested for the removal capacity of total P, total organic carbon (TOC) and Enterococci. Both experiments showed that Polonite removed P significantly ( p < 0.01) better than BFS. An increase in P removal efficiency of 29.3% was observed for the Polonite filter at the lower concentration of BOD7 ( p < 0.05). Polonite was also better than BFS with regard to removal of TOC, but there were no significant differences between the two filter materials with regard to removal of Enterococci. The reduction in Enterococci was greater in the experiment using wastewater with high BOD7, an effect attributable to the higher concentration of bacteria in that wastewater. Overall, the results demonstrate the importance of extensive pre-treatment of wastewater to achieve good phosphorus removal in reactive bed filters and prolonged filter life.

  • 279.
    Nilsson, Nina
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Increased use of solar energy in commercial buildings by integrating energy storage.2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    From a comparison of available thermal energy storage (TES) technologies it can be concluded that the most mature and suitable storage methods for modern commercial buildings in Sweden are storage tanks, either for heat or cold energy, and underground storage solutions such as borehole thermal energy storage (BTES), aquifer storage and energy piles. In this study an integrated solar energy storage system for heating purpose has been designed with BTES, hot water storage tank(s) and solar thermal collectors. The system has been constructed for three different reference buildings in Stockholm and Malmö using the simulation software Polysun, as to investigate the optimal size of BTES system from an economical and energy perspective. The results showed that the optimal storage dimension for the three reference buildings from an economic perspective for a BTES system was 50 % of a building’s peak power demand for heating and tap warm water. The specific energy demand could be lowered significantly for all three buildings, even if applying a weighting factor on the electricity used for the heat pumps. The investment return in the integrated energy storage system turned out to be positive in most cases; however the net present value (NPV) was negative for some of the storage dimensions in the sensitivity analysis. The conclusion from the study is that BTES systems have potential to increase the use of solar energy in modern commercial buildings in a cost effective way, making it easier to reach the future goals of near zero energy buildings (NZEB).

  • 280.
    Noorian-Bidgoli, Majid
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    A review of numerical modeling of strength and stability of underground openings considering hydro-mechanical effect2011Report (Refereed)
  • 281.
    Noorian-Bidgoli, Majid
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Stability analysis and support system design of tunnel portal in the discontinuous media: a case study2011Conference paper (Refereed)
  • 282.
    Noorian-Bidgoli, Majid
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Strength and deformability of fractured rocks2014Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis presents a systematic numerical modeling framework to simulate the stress-deformation and coupled stress-deformation-flow processes by performing uniaxial and biaxial compressive tests on fractured rock models with considering the effects of different loading conditions, different loading directions (anisotropy), and coupled hydro-mechanical processes for evaluating strength and deformability behavior of fractured rocks. By using code UDEC of discrete element method (DEM), a series of numerical experiments were conducted on discrete fracture network models (DFN) at an established representative elementary volume (REV), based on realistic geometrical and mechanical data of fracture systems from field mapping at Sellafield, UK. The results were used to estimate the equivalent Young’s modulus and Poisson’s ratio and to fit the Mohr-Coulomb and Hoek-Brown failure criteria, represented by equivalent material properties defining these two criteria.

    The results demonstrate that strength and deformation parameters of fractured rocks are dependent on confining pressures, loading directions, water pressure, and mechanical and hydraulic boundary conditions. Fractured rocks behave nonlinearly, represented by their elasto-plastic behavior with a strain hardening trend. Fluid flow analysis in fractured rocks under hydro-mechanical loading conditions show an important impact of water pressure on the strength and deformability parameters of fractured rocks, due to the effective stress phenomenon, but the values of stress and strength reduction may or may not equal to the magnitude of water pressure, due to the influence of fracture system complexity. Stochastic analysis indicates that the strength and deformation properties of fractured rocks have ranges of values instead of fixed values, hence such analyses should be considered especially in cases where there is significant scatter in the rock and fracture parameters. These scientific achievements can improve our understanding of fractured rocks’ hydro-mechanical behavior and are useful for the design of large-scale in-situ experiments with large volumes of fractured rocks, considering coupled stress-deformation-flow processes in engineering practice. 

  • 283.
    Noorian-Bidgoli, Majid
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Jing, Lanru
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Anisotropy of strength and deformability of fractured rocks2014In: Journal of Rock Mechanics and Geotechnical Engineering, ISSN 1674-7755, Vol. 6, no 1, p. 156-164Article in journal (Refereed)
    Abstract [en]

    Anisotropy of the strength and deformation behaviors of fractured rock masses is a crucial issue fordesign and stability assessments of rock engineering structures, due mainly to the non-uniform and nonregulargeometries of the fracture systems. However, no adequate efforts have been made to study thisissue due to the current practical impossibility of laboratory tests with samples of large volumes containingmany fractures, and the difficulty for controlling reliable initial and boundary conditions forlarge-scale in situ tests. Therefore, a reliable numerical predicting approach for evaluating anisotropy offractured rock masses is needed. The objective of this study is to systematically investigate anisotropy ofstrength and deformability of fractured rocks, which has not been conducted in the past, using a numericalmodeling method. A series of realistic two-dimensional (2D) discrete fracture network (DFN)models were established based on site investigation data, which were then loaded in different directions,using the code UDEC of discrete element method (DEM), with changing confining pressures. Numericalresults show that strength envelopes and elastic deformability parameters of tested numerical modelsare significantly anisotropic, and vary with changing axial loading and confining pressures. The resultsindicate that for design and safety assessments of rock engineering projects, the directional variations ofstrength and deformability of the fractured rock mass concerned must be treated properly with respectto the directions of in situ stresses. Traditional practice for simply positioning axial orientation of tunnelsin association with principal stress directions only may not be adequate for safety requirements.Outstanding issues of the present study and suggestions for future study are also presented.

  • 284.
    Noorian-Bidgoli, Majid
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Jing, Lanru
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Effects of loading conditions on strength and deformability of fractured rocks - A numerical study2014In: Rock Engineering and Rock Mechanics: Structures in and on Rock Masses - Proceedings of EUROCK 2014, ISRM European Regional Symposium, Taylor & Francis Group, 2014, p. 365-368Conference paper (Refereed)
    Abstract [en]

    This paper presents a systematic numerical study to evaluate the effects of two different loading conditions, namely the axial stress and axial velocity, on testing compressive strength and deformability properties of fractured rocks. The UDEC code was used to perform a series of numerical tests on two-dimensional fracture network (DFN) models, in the similar ways for the uniaxial and biaxial laboratory testing on intact rock samples. The obtained stresses and strains from these numerical experiments were used to estimate equivalent directional Young's modulus and fit the Mohr-Coulomb and Hoek-Brown failure criteria, represented by equivalent material properties defining these two criteria. The numerical results show that stress-strain behaviors changes by loading conditions with higher averaged axial stress under axial velocity condition than that under axial stress condition. Therefore, the effects of different loading conditions should be carefully considered for designing and interpretation of results for in-situ experiments with large volumes of fractured rocks.

  • 285.
    Noorian-Bidgoli, Majid
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Jing, Lanru
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Stochastic analysis of strength and deformability of fracture rocks using multi-fracture system realizationsManuscript (preprint) (Other academic)
    Abstract [en]

    In this paper, a systematic numerical framework is presented to predict stochastic variationsof strength and deformation parameters of fracture rocks, using multiple realizations ofstochastic discrete fracture network (DFN) models at established representative elementaryvolume (REV). Fifty 2D square geometrical models, which are generated using the MonteCarlo technique of the fracture system based on the data obtained from a real site, aregenerated for stochastic analysis of results of stress-deformation behaviors from a series of350 compressive numerical experiments, using the discrete element method (DEM). The Chi-Squared goodness-of-fit test was used to frequency and probability and cumulativedistribution functions (PDF-CDF) of the strength and deformability of fracture rocksdistributions. The results show that (i) the Young’s modulus and Poisson’s ratio during elasticdeformation stages have normal and lognormal distributions, respectively, (ii) both thefriction angle and cohesion derived from Mohr-Coulomb (M-C) strength criterion obeynormal distributions, (iii) the m and s parameters of Hoek-Brown (H-B) strength criterionhave lognormal distributions. The results of stochastic analysis show that it is a usefultechnique for evaluating random variations of strength and deformability parameters of thefractured rock, in cases where there is significant scatter in the rock and fracture parameters.

  • 286.
    Noorian-Bidgoli, Majid
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. University of Kashan, Iran.
    Jing, Lanru
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Stochastic analysis of strength and deformability of fractured rocks using multi-fracture system realizations2015In: International Journal of Rock Mechanics And Mining Sciences, ISSN 1365-1609, E-ISSN 1873-4545, Vol. 78, p. 108-117Article in journal (Refereed)
  • 287.
    Noorian-Bidgoli, Majid
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Jing, Lanru
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Water pressure effects on strength and deformability of fractured rocks under low confining pressures2015In: Journal of Rock Mechanics and Geotechnical Engineering, ISSN 1674-7755, Vol. 48, no 3, p. 971-985Article in journal (Refereed)
    Abstract [en]

    The effect of groundwater on strength anddeformation behavior of fractured crystalline rocks is one ofthe important issues for design, performance and safetyassessments of surface and subsurface rock engineeringproblems. However, practical difficulties make the directin situ and laboratory measurements of these properties offractured rocks impossible at present, since effects of complexfracture system hidden inside the rock masses cannot beaccurately estimated. Therefore, numerical modeling needs tobe applied. The overall objective of this paper is to deepenour understanding on the validity of the effective stressconcept, and to evaluate the effects of water pressure onstrength and deformation parameters. The approach adopteduses discrete element methods to simulate the coupled stressdeformation-flow processes in a fractured rock mass withmodel dimensions at a representative elementary volume(REV) size and realistic representation of fracture systemgeometry. The obtained numerical results demonstrate thatwater pressure has significant influence on the strength, butwith minor effects on elastic deformation parameters, comparedwith significant influence by the lateral confiningpressure. Also, the classical effective stress concept to fracturedrock can be quite different with that applied in soilmechanics. Therefore, one should be cautious when applyingthe classical effective stress concept to fractured rock media.

  • 288.
    Noorian-Bidgoli, Majid
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Zhao, Zhihong
    Stockholm University.
    Jing, Lanru
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Numerical evaluation of strength and deformability of fractured rocks2013In: Journal of Rock Mechanics and Geotechnical Engineering, ISSN 1674-7755, Vol. 5, no 6, p. 419-430Article in journal (Refereed)
    Abstract [en]

    Knowledge of the strength and deformability of fractured rocks is important for design, construction andstability evaluation of slopes, foundations and underground excavations in civil and mining engineering.However, laboratory tests of intact rock samples cannot provide information about the strength anddeformation behaviors of fractured rock masses that include many fractures of varying sizes, orientationsand locations. On the other hand, large-scale in situ tests of fractured rock masses are economically costlyand often not practical in reality at present. Therefore, numerical modeling becomes necessary. Numericalpredicting using discrete element methods (DEM) is a suitable approach for such modeling because of theiradvantages of explicit representations of both fractures system geometry and their constitutive behaviorsof fractures, besides that of intact rock matrix. In this study, to generically determine the compressivestrength of fractured rock masses, a series of numerical experiments were performed on two-dimensionaldiscrete fracture network models based on the realistic geometrical and mechanical data of fracturesystems from field mapping. We used the UDEC code and a numerical servo-controlled program forcontrolling the progressive compressive loading process to avoid sudden violent failure of the models.The two loading conditions applied are similar to the standard laboratory testing for intact rock samplesin order to check possible differences caused by such loading conditions. Numerical results show thatthe strength of fractured rocks increases with the increasing confining pressure, and that deformationbehavior of fractured rocks follows elasto-plastic model with a trend of strain hardening. The stresses andstrains obtained from these numerical experiments were used to fit the well-known Mohr-Coulomb (MC)and Hoek-Brown (H-B) failure criteria, represented by equivalent material properties defining thesetwo criteria. The results show that both criteria can provide fair estimates of the compressive strengthsfor all tested numerical models. Parameters of the elastic deformability of fractured models during elasticdeformation stages were also evaluated, and represented as equivalent Young’s modulus and Poisson’sratio as functions of lateral confining pressure. It is the first time that such systematic numerical predictingfor strength of fractured rocks was performed considering different loading conditions, with importantfindings for different behaviors of fractured rock masses, compared with testing intact rock samples undersimilar loading conditions.

  • 289.
    Norrman, Jenny
    et al.
    Chalmers, Dept Civil & Environm Engn, Div GeoEngn, S-41296 Gothenburg, Sweden.;Swedish Geotech Inst, S-41296 Gothenburg, Sweden..
    Sparrenbom, Charlotte J.
    Lund Univ, Dept Geol, S-22362 Lund, Sweden..
    Berg, Michael
    Eawag, Swiss Fed Inst Aquat Sci & Technol, CH-8600 Dubendorf, Switzerland..
    Nhan, Dang Duc
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Harms-Ringdahl, Peter
    Nhan, Pham Quy
    Rosqvist, Håkan
    Tracing sources of ammonium in reducing groundwater in a well field in Hanoi (Vietnam) by means of stable nitrogen isotope (delta N-15) values2015In: Applied Geochemistry, ISSN 0883-2927, E-ISSN 1872-9134, Vol. 61, p. 248-258Article in journal (Refereed)
    Abstract [en]

    In the Southern part of Hanoi, high ammonium (NH4+) concentrations in reducing groundwater have been an issue over the last 25 years. Elevated NH4+ concentrations in groundwater, in general, are an indicator of influences from anthropogenic sources, but the buried peat layers in the Red River delta formation are also hypothesized to contribute to the high NH4+ levels (up to 100 mg/l). We traced the sources of NH4+ at the Nam Du well field of the Hanoi water works by means of isotope ratios (N-15/N-14). The delta N-15 values were determined for total sedimentary N and exchangeable NH4+ of the peat material, and for NH4+ dissolved in deep and shallow groundwater, sewage, and surface water. Groundwater NH4+ of the upper (Holocene) and the lower (Pleistocene) aquifers had higher delta N-15 values than did total N and NH4+ of the sediments, and were somewhat higher than the delta N-15 values of NH4+ in sewage and surface water. We conclude that the present conditions of temperature and pH tend to promote deprotonation of NH4+ to ammonia (NH3), which eventually degasses from the groundwater table to the unsaturated pore space. This can cause an enrichment of N-15 in the remaining NH4+, as the lighter N-14 in NH3 is volatilized at a slightly faster rate. The intermediate delta N-15 values within the Pleistocene aquifer can be explained by the recharge thereto, which is a mixture of the high delta N-15 values of the Holocene aquifer and the low delta N-15 values of water infiltrating from the Red River into the Pleistocene aquifer. Some part of the increased groundwater NH4+ is likely to arise from anthropogenic activities, as supported by several indications: a large drawdown in the Pleistocene aquifer caused by Hanoi's extensive water abstraction and subsequent downward gradient from the upper Holocene aquifer; the presence of coliforms in groundwater; and a positive correlation between ammonium and DOC, Cl, Br and Ni, but a lack of correlation with As. However, the much higher concentrations of NH4+ in the groundwater compared to the potential surface sources, the positive correlation between NH4+ and DOC, the abundance of natural organic matter (OM), the amount of exchangeable NH4+ in the sediments, and the highly reducing conditions in the aquifers indicate that N-mineralization of organic N from the peat contribute substantially to the high NH4+ levels in groundwater of the Nam Du well field.

  • 290.
    Ograbek, Ewa
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Monitoring and controlling of deammonification process in pilot-scale IFAS system.2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In recent years, Anammox process has been investigated extensively. Today is successfully used for treatment of supernatant from dewatering of digested sludge having a high concentration of ammonia nitrogen. Currently, studies are carried out for the application of this system for the main waste water stream, which has a low concentration of ammonium nitrogen.

    The aim of the study was to find the optimal conditions for the activity of Anammox bacteria at low concentrations of ammonia nitrogen, a constant temperature of 25ºC and changing values of biomass in IFAS system. More than that, an assessment of the ongoing process through chemical analysis, physical parameters observation and verification data collected by the online system. Data from the online system have been revised in order to determine the useful and reliable of relevant devices.

    Each week once/twice analyses of the chemical parameters through laboratory analysis were performed by using Dr. Hach Lange cuvettes. Physical parameters were measured by portable devices to verify the data collected by the online system. All these activities had been made in each, of the four different, periods of the reactor operation.

    It is difficult to find optimal conditions for the Anammox bacteria that are susceptible to any change inside the reactor. For the evaluation of the process, after changing the parameters inside the reactor, it is necessary to keep time to adapt to new conditions by bacteria.

  • 291.
    Olofsson, Bo
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Rasul, Hedi
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Lundmark, Annika
    Spread of Water-Borne Pollutants at Traffic Accidents on Roads2017In: Water, Air and Soil Pollution, ISSN 0049-6979, E-ISSN 1573-2932, Vol. 228, no 9, article id 323Article in journal (Refereed)
    Abstract [en]

    Traffic accidents sometimes lead to the spread of hazardous compounds to the environment. Accidental spills of hazardous compounds on roads in the vicinity of vulnerable objects such as water supplies pose a serious threat to water quality and have to be assessed. This study compared three different assessment methods, electrical resistivity measurements, analytical flow calculations, and 1D and 2D dynamic flow modeling, to describe rapid transport processes in the road shoulder and roadside verge after a major spill. The infiltration and flow paths of water-borne substances were described during simulated discharge of pollutants on different road types. Full-scale tracer tests using sodium chloride were carried out at nine different road locations in Sweden. Analysis of grain size distribution and infiltrometer tests were carried out at the road shoulder and verges. The pathways and travel times were traced using resistivity measurements and 3D inverse modeling. The resistivity measurements were compared to analytical flow calculations and 1D and 2D dynamic modeling. All measurement sites were highly heterogeneous, which caused preferential flow. Vertical flow velocities of 1.4-8.6 x 10(-4) m/s were measured. The results of the analytical calculations and flow modeling were of the same order of magnitude. The measurements showed that almost all infiltration goes directly into the road embankment, hence the composition and structure of the built-up road must be considered. The non-destructive resistivity measurements and 3D modeling provided useful information for clarifying the infiltration and flow pattern of water-borne compounds from road runoff.

  • 292.
    Olsson, Bengt
    et al.
    SLU.
    Hannrup, Björn
    SkogForsk.
    Jönsson, Marie
    SLU.
    Larsolle, Anders
    SLU.
    Nordström, Maria
    SkogForsk.
    Mörtberg, Ulla
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Rudolphi, Jörgen
    SLU.
    Strömgren, Maria
    SLU.
    A decision support model for individual tree stump harvesting options based on criteria for economic return and environmental protection2017In: Scandinavian Journal of Forest Research, ISSN 0282-7581, E-ISSN 1651-1891, Vol. 32, p. 246-259Article in journal (Refereed)
    Abstract [en]

    Based on principles of multi-criteria analysis techniques, a model (MAPStump-E) for decision support on stump harvesting at stand level was developed. The model applies the concept that each stump can be attributed production values (economic) and environmental values (here soil protection and water quality). Individual tree stump information was incorporated directly from the production reports of harvesters and combined with high-resolution Geographical Information System data on topography and soil type to create a production submodel and a soil and water vulnerability submodel (SWM). To test the model, it was applied to a 45-ha study forest in south-central Sweden and the outcome of nine scenarios with varying bioenergy prices and environmental protection levels was examined. Combined analysis of the effects of production and environmental criteria on total dry mass of harvestable stumps at the study site showed that biomass prices had a stronger influence than environmental criteria. Conflict stumps were defined as stumps suitable for harvest based on production criteria, but unsuitable based on soil and water protection criteria. In a ?medium? price scenario, the proportion of conflict stumps at the study site ranged from 6% to 18%, depending on protection level set.

  • 293. Oni, S. K.
    et al.
    Mieres Dinamarca, Francisco
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Futter, M. N.
    Laudon, H.
    Soil temperature responses to climate change along a gradient of upland–riparian transect in boreal forest2017In: Climatic Change, ISSN 0165-0009, E-ISSN 1573-1480, Vol. 143, no 1-2, p. 27-41Article in journal (Refereed)
    Abstract [en]

    There is growing evidence of climate change impacts on northern ecosystems. While most climate change studies base their assessments on air temperature, spatial variation of soil temperature responses have not been fully examined as a metric of climate change. Here we examined spatial variations of soil temperature responses to an ensemble of regional climate model (RCM) projections at multiple depths in upland and riparian zones in the Swedish boreal forest. Modeling showed a stronger influence of air temperature on riparian soil temperature than was simulated for upland soils. The RCM ensemble projected a warming range of 4.7–6.0 °C in riparian and 4.3–5.7 °C in upland soils. However, soils were slightly colder in the riparian zone during winter. While the historical record showed that upland soils are about 0.4 °C warmer than the riparian soils, this may be reversed in the future as model projections showed that on an annual basis, riparian soils might be slightly warmer by 0.2 to 0.4 °C than upland soils. However, upland soils could warm up earlier (April) compared to riparian soils (May).

  • 294.
    Ormachea Muñoz, Mauricio
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. Instituto de Investigaciones Químicas-UMSA.
    Hydrogeochemistry of Naturally Occurring Arsenic and Other Trace Elements in the Central Bolivian Altiplano: Sources, mobility and drinking water quality2015Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The Bolivian Altiplano (BA) is a high plateau located in the western part of the country at an altitude of 3,600 to 3,900 meters above sea level and is bordered by the Eastern and Western Cordillera. Within the BA there is a large endorheic hydrologic system linking the Titicaca Lake in the north the Desaguadero River, lakes Uru-Uru and Poopó in the central part; and the Lacajahuira River and Coipasa and Uyuni salt pans in the south. Several mineralized areas, especially in the Eastern Cordillera, have been intensively exploited for centuries for the extraction of silver, gold, and tin from polymetallic sulfide ore deposits. Presently many urban centers are also contributing for an extensive contamination in localized areas; especially the Poopó Lake and some rivers are affected by high loads of wastewater and solid waste, in addition to the release of heavy metals and arsenic (As) due to acid mine drainage.

    The presence of As in the BA was known to be related to mining only, but recent studies revealed that As of geogenic origin also contributing to the elevated concentration of As in surface and groundwater. The Poopó Lake basin is characterized by a semiarid climate. Geologic formations predominantly are of volcanic origin and groundwater flow is sluggish in nature. These environmental settings have generated substantially elevated concen- trations of geogenic As and other trace elements in surface and groundwater. Both surface and groundwater used for drinking water have high concentrations of As that by far exceed the World Health Organization (WHO) guideline. The overall objective of the present study has been focused on the determination of the sources and principal mechanisms for mobilization of geogenic As into surface and groundwater of the Poopó Lake basin area. More specifically, this study has determined the spatial distribution and the extent of As contamination in surface and groundwater; chemical composition of surface and groundwater, rock and sediment; major geochemical mechanisms for As mobilization from solid phase to aqueous phases. This study also made an assessment of drinking water quality in rural areas within the Poopó Lake basin.

    Arsenic concentration exceeded the WHO guideline and national regulations for drinking water of 10 µg/L in 85% of the samples collected from the area around the Poopó Lake (n=27) and 90% of the samples from the southern part of the lake basin (n=42). Groundwater samples collected from drinking water wells had As concentrations up to 623 µg/L, while samples collected from piezometers had even higher up to 3,497 µg/L. Highest concentration in river water samples was observed 117 µg/L. Alkaline nature of water (median pH 8.3 for groundwater and 9.0 for surface water), predominance of Na-Cl-HCO3 water type and elevated Eh reflecting oxidized character has been revealed by As(V) as the major species in As speciation. Different rock types were analyzed for their As content and the highest concentration of 27 mg/kg was found in a coral limestone sample. In evaporate it was 13 mg and 11 mg As/kg was measured in calcareous sandstone. Elevated concentration of As was also observed in sediment cores collected from two drilling sites; 51 mg/kg in Condo K and 36 mg/kg in Quillacas. Physical and chemical weathering of volcanic rocks, limestone, carbonates and plagioclase minerals enhance the supply of Na+ and HCO3- into solution and as a consequence pH and alkalinity increase, which in turn, favor As desorption from solid mineral surfaces (especially Fe(III) oxyhydr- oxides) and therefore dissolved As in water is increased.

  • 295.
    Ormachea Muñoz, Mauricio
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Garcia Arostegui, Jose L.
    Garcia Moreno, Maria E.
    Kohfahl, Claus
    Quintanilla, Jorge
    Hornero Diaz, Jorge
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Geochemistry of naturally occurring arsenic in groundwater and surface-water in the southern part of the Poopó Lake basin, Bolivian Altiplano2016In: Groundwater for Sustainable Development, ISSN 2352-801X, Vol. 2-3, p. 104-116Article in journal (Refereed)
    Abstract [en]

    Groundwaters from shallow aquifers and surface water from rivers of the southern part of Poopó Lake basin within the Bolivian Altiplano have significant quality problems such as high salinity and high concentrations of arsenic (As). The extent of As contamination is observed in the studied groundwater over large parts of the study area. Surface-waters are generally alkaline (pH 8.2–8.7) and oxidizing with dissolved oxygen (DO) concentrations in a range of 2.5–6.6 mg/L The water chemistry is predominantly of Na–Cl–HCO3–type, with concentrations of dissolved As in the range of 8.6–117 µg/L with As(V) as the main aqueous species. The concentration of Li varies in the range of 1.1–4.4 mg/L, while other trace elements occur in low concentrations. Groundwaters have a very large range of chemical compositions and the spatial variability of As concentrations is considerable over distances of a few km; dissolved As in groundwater spans over 4 orders of magnitude (3–3497 µg/L), while concentrations of Li have a range of 0.05–31.6 mg/L. Among the investigated drinking-water wells, 90% exceed the WHO guideline value of 10 µg As/L. Electrical conductivity ranges between 295 and 20,900 µS/cm; high salinity is resulting from evaporation under ambient semi-arid climatic conditions. The pH values of the groundwaters are generally slightly alkaline (5.5–8.7) and universally oxidizing, under these conditions As(V) is the prevalent specie. Groundwater As correlates positively with pH, electrical conductivity, Cl, Na+, HCO3 , Ca2+ and SO4 2−. Weathering/dissolution of carbonates, evaporites, halite and plagioclase minerals incorporate Na+ and HCO3 in solution with consequent pH and alkalinity increase; these are favorable conditions for high mobility of As species. Stable isotopic signatures indicate recharge at the Altiplano with seasonal effects. All surface water and some groundwater samples are enriched due to evaporation, which probably increased concentration of dissolved As.

  • 296.
    Ormachea Muñoz, Mauricio
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Wern, Hannes
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Johnsson, Fredrick
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Sracek, O.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Quintanilla, J.
    Bundschuh, Jochen
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Geogenic arsenic and other trace elements in the shallow hydrogeologic system of Southern Poopó Basin, Bolivian Altiplano2013In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 262, p. 924-940Article in journal (Refereed)
    Abstract [en]

    Environmental settings in the southern area of Lake Poopó in the Bolivian highlands, the Altiplano, have generated elevated amounts of arsenic (As) in the water. The area is characterised by a semiarid climate, slow hydrological flow and geologic formations of predominantly volcanic origin. The present study aimed at mapping the extent of the water contamination in the area and to investigate the geogenic sources and processes involved in the release of As to the groundwater.Ground- and surface-water samples were collected from 24 different sites, including drinking water wells and rivers, in the southern Poopó basin in two different field campaigns during the dry and rainy seasons. The results revealed variable levels of As in shallow drinking water wells and average concentration exceeding the WHO guidelines value. Arsenic concentrations range from below 5.2μg/L (the detection level) to 207μg/L and averages 72μg/L. Additionally, high boron (B) concentrations (average 1902μg/L), and high salinity are further serious concerns for deteriorating the groundwater quality and rendering it unsuitable for drinking. Groundwater is predominantly of the Na-Cl-HCO3 type or the Ca-Na-HCO3 type with neutral or slightly alkaline pH and oxidising character. While farmers are seriously concerned about the water scarcity, and on a few occasions about salinity, there are no concerns about As and B present at levels exceeding the WHO guidelines, and causing negative long term effects on human health.Sediment samples from two soil profiles and a river bed along with fourteen rock samples were also collected and analysed. Sequential extractions of the sediments together with the calculation of the mineral saturation indices indicate that iron oxides and hydroxides are the important secondary minerals phases which are important adsorbents for As. High pH values, and the competition of As with HCO3 and dissolved silica for the adsorption sites probably seems to be an important process for the mobilisation of As in the shallow groundwaters of the region. Continuous monitoring and expansion of monitoring systems are necessary prerequisites for better understanding of the pattern of As mobilisation in the Southern Poopó Basin.

  • 297. Oskooi, Behrooz
    et al.
    Henkel, Herbert
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Pedersen, Laust B.
    Bäckstrom, Ann
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Abedi, Maysam
    Magnetotelluric investigation on Bjorko impact structure, west of Stockholm, Sweden2016In: Arabian Journal of Geosciences, ISSN 1866-7511, E-ISSN 1866-7538, Vol. 9, no 13, article id 618Article in journal (Refereed)
    Abstract [en]

    This paper describes the application of magnetotelluric (MT) method to investigate Bjorko impact structure located at west of Stockholm, Sweden. This structure has formed in crystalline rocks ca. 1.2 Ga ago and located relatively close to the district heating infrastructure of the Stockholm region, as the largest district heating system in Europe. Since impact structures mostly contain fractured rock volumes in the form of breccia formations, the occurred brecciation zones in this region are more favorable potential targets for geothermal investigations. The main objective is evaluating the capability of the study area to have potential for geothermal resources by mapping the subsurface structure. To image electrical characteristic of underground layers, 1D and 2D bimodal inversions of TE and TM modes of MT data are performed. The results are also compared with the outputs of the inversion of the determinant data (yielding a direction independent average of the subsurface conductivity) along the same profiles, proving good accordance of the outputs. The processed resistivity sections at depth along with measuring various rock physical properties across two drilled boreholes at Bjorko and Midsommar islands localized two conductors at depths of 1 km and from 2.5 to 4.5 km, which may be attributed to be a potential zone for geothermal energy retrieval.

  • 298.
    Ouvrard, Elsa
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Applying Earth Observation services to detect non-authorised water abstractions in the EU.2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In Europe, about 353 km3 of water are abstracted every year from natural resources . Water resources are used for very diverse activities including, energy production, agriculture, domestic uses and industry. Competing uses between the different sectors can lead to overabstraction where demand exceeds resources availability. The 2012 Blueprint to Safeguard Europe’s Water Resources identified non-authorised water abstractions, i.e. water abstractions without permits or exceeding the authorised amounts, as a cause of overabstraction and advocates the surveillance of water abstractions in each Member State .

    This thesis report aims at studying the potential of Earth Observation technologies to detect non-authorised water abstractions. It briefly introduces the existing legal framework for water abstraction in Europe in order to better understand current challenges for the detection of non-authorised water abstraction and tries to assess the strengths and weaknesses of methods, for the detection of illegal withdrawals, relying on Earth Observation-derived data.

    The combination of field measurements with Earth Observation-derived information addresses a certain number of issues experienced with the traditional field measurements alone approach (e.g. time and cost efficiency). However, it does not solve other issues related to governance and administrative aspects and heavily relies on weather and climatic conditions, which make Earth Observation methods non compatible with some regions in the European Union (EU). Besides this approach requires having access to a large number of data and major efforts are necessary to ensure a good coordination and communication between the different competent authorities responsible for the management of water abstractions and the entities which own the required data.

  • 299.
    Owusu-Agyeman, Isaac
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Malovanyy, Andriy
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Plaza, Elzbieta
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Pre-concentration of ammonium to enhance treatment of wastewater using the partial nitritation/anammox process2015In: Environmental technology, ISSN 0959-3330, E-ISSN 1479-487X, Vol. 36, no 10, p. 1256-1264Article in journal (Refereed)
    Abstract [en]

    The anaerobic ammonium oxidation (anammox) process is one of the most cost-effective technologies for removing excessive nitrogen compounds from effluents of wastewater treatment plants. The study was conducted to assess the feasibility of using ion exchange (IE) and reverse osmosis (RO) methods to concentrate ammonium to support partial nitritation/anammox process, which so far has been used for treating only wastewater with high concentrations of ammonium. Upflow anaerobic sludge blanket (UASB) reactor effluents with 40.40, 37.90 and 21.80 mg NH4N/L levels were concentrated with IE method to 367.20, 329.50 and 187.50 mg NH4N/L, respectively, which were about nine times the initial concentrations. RO method was also used to concentrate 41.0 mg NH4N/L of UASB effluent to 163 mg NH4N/L at volume reduction factor 5. The rates of nitrogen removal from respective RO pretreated concentrates by partial nitritation/anammox technology were 0.60, 1.10 and 0.50 g N/m(2)day. The rates were largely influenced by initial nitrogen concentration. However, rates of RO concentrates were 0.74, 0.92 and 0.81 g N/m(2)day even at lower initial NH4N concentration. It was found out from the study that higher salinity decreased the rate of nitrogen removal when using partial nitritation/anammox process. Dissolved oxygen concentration of similar to 1 mg/L was optimal for the operation of the partial nitritation/anammox process when treating IE and RO concentrates. The result shows that IE and RO methods can precede a partial nitritation/anammox process to enhance the treatment of wastewater with low ammonium loads.

  • 300.
    Pang, Xi
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Modelling trade-offs between forest bioenergy and biodiversity2016Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Globally, biodiversity is declining due to loss, fragmentation and degradation of habitat, which undermines ecosystem functioning and therefore threatens also the ability of ecosystems to supply ecosystem services. Moreover, there is a need for adapting to climate change as well as securing the supply of energy, which have led to a shift in energy consumption from fossil fuel to renewables, especially biomass, which in turn put increasing pressure on ecosystems and biodiversity. In Sweden, forest bioenergy has an important role, and high forest biomass production is an important societal objective. Intensified forestry could increase the biomass production through monocultures of native or introduced tree species as well as forest fertilization. However, due to negative effects on natural forest structures and processes, a more intensive forestry could be detrimental to forest biodiversity. The balance between energy demand and the long-term capacity of ecosystems to supply goods and services as well as support biodiversity is therefore crucial. The existing energy models and research have relatively low concerns on land use, landscape and biodiversity, comparing with high enthusiastic on energy economics, climate change and greenhouse gas emission research. Consequently, it would be difficult to provide comprehensive decision support by using only these economy and climate change oriented tools. However, ecological assessment models and multi-criteria approaches exist with great potential for linking with suitable energy models. This will enable the development of more comprehensive decision support tools for assessing future energy scenarios, integrating main policy concerns when assessing renewable energy options. The research was based on a survey on existing energy models and a case study of forest biomass extraction in Kronoberg, a region in southern Sweden. The aim of this project was to develop and test methods for integrated the sustainability assessment of forest biomass extraction for bioenergy purposes by incorporating effects on biodiversity. Forest growth was simulated under two management scenarios: Even-aged-forestry (EAF) and continuous-cover-forestry (CCF), in a time period between 2010-2110. The GIS-based approaches for assessment of biomass impacts on biodiversity involved an ecological network assessment of prioritized ecological profiles across the landscape under the two scenarios.

     

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