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  • 251.
    Engström, Emma
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Transport and Fate of Escherichia coli in Unsaturated Porous Media2011Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The unsaturated zone could provide an effective barrier against pathogenic microbes entering the groundwater. Knowledge relating to microbial fate in this zone is therefore important for increased understanding of groundwater vulnerability. This thesis examines the published literature that is related to the transport, retention and survival processes that apply to the fecal indicator bacterium Escherichia coli in unsaturated porous media. The main focus concerns the research findings under steady-state flow in homogeneous filter media, and under unfavorable attachment conditions, which are the most common in the natural environment. Experimental results in the literature for the pore-, column- and field-scale are examined and compared to commonly applied theories and modeling approaches. An analysis of the main factors that influence attenuation and biofilm formation is provided. Further, the findings are illustrated in a model of an unplanted, vertical flow constructed wetland. The results indicate that retention at the solid-air-water interface is a major attenuation process. In addition, they suggest that the flow velocity (as dependent on the grain size and the saturation) is a key influencing factor. However, it has not yet been established how the research findings relating to the main processes and influencing factors can be incorporated into predictive models; in the literature, a multitude of models have been proposed and alternative theories could describe the same observation. In this study, the transport and fate of Escherichia coli in different sand filters is, therefore, modeled using various literature models - derived under similar experimental conditions - in order to assess the possibility to compare and generalize the equations, evaluate their implications considering the different saturation settings and filter depths, and to define the spectra of the reduction efficiencies. It is discovered that the bacterial attenuation behaviors vary largely. This calls for clarification regarding the underlying processes. Future research is also recommended to include the ef-fects of structured filter media and sudden changes in the flow rate.

  • 252.
    Engström, Emma
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Management and Assessment.
    Balfors, Berit
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Management and Assessment.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Management and Assessment.
    Modeling bacterial transport and removal in a constructed wetland system2010In: Proceedings of the COMSOL Conference, 2010, Paris, 2010Conference paper (Refereed)
  • 253.
    Engström, Emma
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Balfors, Berit
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Predicting the transport and fate of Escherichia coli in unsaturated sand filters2011In: Journal of Contaminant Hydrology, ISSN 0169-7722, E-ISSN 1873-6009Article in journal (Other academic)
  • 254.
    Engström, Emma
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Management and Assessment.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Management and Assessment.
    Kulabako, Robinah
    Department of Civil Engineering, Makerere University, Kampala, Uganda.
    Balfors, Berit
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Management and Assessment.
    Escherichia coli transport and fate in unsaturated porous media: a literature review of experimental findings and theories relating to processes, models and influencing factors2011In: Critical reviews in environmental science and technology, ISSN 1064-3389, E-ISSN 1547-6537Article in journal (Other academic)
  • 255. Essery, Richard
    et al.
    Rutter, Nick
    Pomeroy, John
    Baxter, Robert
    Stahli, Manfred
    Gustafsson, David
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Barr, Alan
    Bartlett, Paul
    Elder, Kelly
    An Evaluation of Forest Snow Process Simulations2009In: Bulletin of The American Meteorological Society - (BAMS), ISSN 0003-0007, E-ISSN 1520-0477, Vol. 90, no 8, p. 1120-+Article in journal (Refereed)
    Abstract [en]

    The Northern Hemisphere has large areas that are forested and seasonally snow covered. Compared with open areas, forest canopies strongly influence interactions between the atmosphere and snow on the ground by sheltering the snow from wind and solar radiation and by intercepting falling snow; these influences have important consequences for the meteorology, hydrology, and ecology of forests. Many of the land surface models used in meteorological and hydrological forecasting now include representations of canopy snow processes, but these have not been widely tested in comparison with observations. Phase 2 of the Snow Model Intercomparison Project (SnowMIP2) was therefore designed as an intercomparison of surface mass and energy balance simulations for snow in forested areas. Model forcing and calibration data for sites with paired forested and open plots were supplied to modeling groups. Participants in 11 countries contributed output from 33 models, and the results are published here for sites in Canada, the United States, and Switzerland. On average, the models perform fairly well in simulating snow accumulation and ablation, although there is a wide intermodal spread and a tendency to underestimate differences in snow mass between open and forested areas. Most models capture the large differences in surface albedos and temperatures between forest canopies and open snow well. There is, however, a strong tendency for models to underestimate soil temperature under snow, particularly for forest sites, and this would have large consequences for simulations of runoff and biological processes in the soil.

  • 256.
    Eveborn, David
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Bed filters for phosphorus removal in on-site wastewater treatment: Removal mechanisms and sustainability2010Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    For many surface waters, phosphorus (P) leaching is a serious problem that should be minimized to prevent eutrophication. In Sweden there is a demand for physical and technical development of high-performance P removal techniques to reduce phosphorus leaching from on-site wastewater treatment systems to the Baltic Sea. However, although these systems are designed to reduce eutrophication there are also other environmental impacts to be considered when implementing them in on-site systems; energy use and global warming potential are two examples. This study has investigated several bed filter materials (reactive media and natural soils) for their total environmental impact (in commercial applications) as well as for the predominating chemical phosphorus removal mechanisms. The use of life cycle assessment revealed that several reactive bed filters are relatively energy-consuming due to the material manufacturing process. Characterization of phosphorus compounds in used reactive media provided evidence for calcium phosphate precipitation as the predominating P removal mechanism in alkaline filter materials. However, in soil treatment systems with noncalcareous soils, batch experiments and extractions suggested that aluminium compounds were important for P removal. According to mass balance calculations that compared accumulated P with the estimated P load in a soil treatment system, the long term P removal capacity was very low; only 6.4 % of the applied phosphorus had been removed during 16 years of operation.

  • 257.
    Eveborn, David
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Sustainable phosphorus removal in onsite wastewater treatment2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Aquatic eutrophication is a serious environmental problem that occurs all over the world. To protect surface waters (in particular the Baltic Sea), the regulatory pressure on onsite wastewater treatment (OWT) systems have increased in Sweden. Stringent requirements have led to uncertainties regarding the capability of conventional treatment techniques (soil treatment systems (STS)) to remove phosphorus (P), but they have also stimulated the development and introduction of enhanced P treatment techniques. In this thesis the accumulation and mobility of P as well as the chemical P removal mechanisms were studied in soils and reactive filter media. This knowledge was then used in environmental systems analysis. A model based on life cycle assessment (LCA) methodology was developed to evaluate the overall environmental performance of conventional and enhanced P treatment systems under various local conditions. The P accumulation in the studied STS varied (320-870 g m-3) and the accumulated P was rather mobile in some soils. Phosphorus compounds were identified in alkaline reactive filter media (calcium phosphates predominated) by means of X-ray Absorption Near Edge Structure (XANES). In sandy soils from STS aluminium was found to be a key element for P removal, as evidenced by a strong relationship between oxalate-extractable P and Al. The LCA studies indicated that enhanced P treatment systems may be beneficial from an eutrophication and P recycling perspective but causes increased impacts in terms of global warming and acidification. Despite the drawbacks, enhanced P treatment techniques should be considered suitable substitutes to surface water discharge STS under most conditions. This is because the latter systems have such a strong eutrophication impact. On the other hand, under appropriate conditions, STS with groundwater discharge may be advantageous. These systems generally caused low environmental impacts except for the dispersion of P resources. 

  • 258.
    Eveborn, David
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Geochemistry and Ecotechnology. KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. JTI - Swedish Institute of Agricultural and Environmental Engineering, Sweden .
    Gustafsson, Jon Petter
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Geochemistry and Ecotechnology. KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. Department of Soil and Environment, Swedish University of Agricultural Sciences, Sweden.
    Elmefors, Elin
    JTI,Swedish Institute of Agricultural and Environmental Engineering.
    Yu, Lin
    Center for Environmental and Climate Research (CEC), Lund University.
    Eriksson, Ann-Kristin
    Department of Soil and Environment, Swedish University of Agricultural Sciences.
    Ljung, Emelie
    JTI,Swedish Institute of Agricultural and Environmental Engineering.
    Renman, Gunno
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Phosphorus in soil treatment systems: accumulation and mobility2014In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 64, p. 42-52Article in journal (Refereed)
    Abstract [en]

    In several western countries, septic tanks with subsequent soil treatment systems (STS) are a common treatment technique for domestic wastewater in rural areas. However the suitability of STS (especially relatively close to surface waters) can be questioned since the discharge of phosphorus (P) from such effluents is not well known. In this study, six STS in Sweden (11 to 28 years old) were investigated by means of batch and column experiments on samples taken from the unsaturated subsoil beneath the distribution pipes. At all sites the wastewater had clearly influenced the soil. This was observed through decreased pH, increased amounts of oxalate extractable metals and altered P sorption properties. The amount of accumulated P in the STS (defined as the amount of total P in the STS samples minus the amount of total P in unused soil samples) were found to be between 0.32 and 0.87 kg m-3, which in most cases was just a small fraction of the estimated P load (< 30%). Column studies revealed that remarkably high P concentrations (up to 6 mg L-1) were leached from the material when deionized water was applied. However, the response to deionized water varied between the sites. The affinity for P in the soils was well correlated to the amount of oxalate-extractable aluminium (as evidenced by a strong relationship between oxalate-extractable Al and oxalate-extractable P) and generally soils with high content of oxalate extractable Al was also less vulnerable to P leakage.

  • 259.
    Eveborn, David
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Geochemistry and Ecotechnology.
    Gustafsson, Jon Petter
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Geochemistry and Ecotechnology.
    Hesterberg, Dean
    University Raleigh, Department of Soil Science, North Carolina, USA.
    Hillier, Stephen
    Macaulay Institute, Craigiebuckler, Aberdeen, UK.
    XANES Speciation of P in Environmental Samples: An Assessment of Filter Media for on-Site Wastewater Treatment2009In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 43, no 17, p. 6515-6521Article in journal (Refereed)
    Abstract [en]

    X-ray absorption near edge structure (XANES) spectroscopyis a useful technique for characterization of chemical speciesof phosphorus in complex environmental samples. To developand evaluate bed filters as sustainable on-site wastewater treatment solutions, our objective in this study was to determine the chemical forms of accumulated phosphorus in a selectionof promising filter materials: Filtralite P, Filtra P, Polonite, Absol, blast furnace slag, and wollastonite. Full-scale operational wastewater-treatment systems were sampled and in addition, filter samples collected from laboratory studies provided access to additional media and complementary samples.Phosphorus species were characterized using phosphorus K-edge XANES spectroscopy, complemented by X-ray powder diffraction (XRPD) and attenuated total reflectance Fouriertransform infrared spectroscopy (ATR-FTIR). No systematic differences could be seen in the results between laboratory and full-scale samples. All six filter media contained significant amounts of crystalline calcium phosphates. Some samples also contained amorphous calcium phosphate (>60 % of totalP in Absol). In Filtralite P and blast furnace slag, more than 35 % of the accumulated phosphorus was associated with Fe or Al. Both the power and shortcomings of XANES analysis for characterizing P species in these filter media are discussed.

  • 260.
    Eveborn, David
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Kong, Deguo
    Department of Applied Environmental Science, Stockholm University, Sweden.
    Gustafsson, Jon Petter
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Wastewater treatment by soil infiltration: Long-term phosphorus removal2012In: Journal of Contaminant Hydrology, ISSN 0169-7722, E-ISSN 1873-6009, Vol. 140, p. 24-33Article in journal (Refereed)
    Abstract [en]

    Phosphorus (P) leaching from on-site wastewater treatment systems may contribute to eutrophication. In developed countries the most common on-site treatment technique is septic systems with soil infiltration. However, the current knowledge about long term P removal in soil treatment systems is not well developed and the data used for estimation of P losses from such systems are unreliable. In this study we sampled four filter beds from community-scale soil treatment systems with an age of between 14 and 22 years to determine the long-term P removal and to investigate the chemical mechanisms behind the observed removal. For one site the long-term P removal was calculated using a mass balance approach. After analysis of the accumulated P. it was estimated that on average 12% of the long-term P load had been removed by the bed material. This indicates a low overall capacity of soil treatment systems to remove phosphorus. Batch experiments and chemical speciation modelling indicated that calcium phosphate precipitation was not an important long-term P removal mechanism, with the possible exception of one of the sites. More likely, the P removal was induced by AlPO4 precipitation and/or sorption to poorly ordered aluminium compounds, as evidenced by strong relationships between oxalate-extractable Al and P.

  • 261.
    Eveborn, David
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Sörelius Kiessling, Helene
    JTI - Swedish Institute of Agricultural and Environmental Engineering.
    Environmental systems analysis on enhanced phosphorus removal in onsite wastewater treatmentManuscript (preprint) (Other academic)
    Abstract [en]

    In order to minimize phosphorus (P) loads to surface waters, the regulatory pressure on onsite wastewater treatment systems has increased. However, the environmental side-effects of implementing secondary P treatment have not been seriously reviewed. In this study we hypothesized that local conditions will largely govern the overall environmental benefits and drawbacks of different options for onsite wastewater treatment from a regional perspective. To explore the validity of this hypothesis an environmental systems analysis (ESA) model was developed that could handle differences in local conditions. The model was applied for four different treatment options, two conventional and two enhanced P treatment options. In a sensitivity analysis three diverse local contexts (type cases) were configured to evaluate the overall environmental impacts from the local and the regional perspective. The evaluation indicated that the eutrophication impacts from onsite wastewater treatment systems are significant in relation to the mean per capita contributions. This statement was valid even at a regional perspective as long as the natural retention was not very strong. Thus, the environmental side effects (increased emissions of greenhouse gases (GHG) and acidifying substances) of implementation of enhanced treatment solutions might be justifiable in many situations. However, due to a low impact in most of the studied environmental aspects, groundwater discharging soil treatment systems (STS) seemed to be preferable in areas were hydrogeological conditions are satisfactory and the distance to surface water is sufficient.

  • 262.
    Ezquerro, Ander
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Struvite Precipitation and Biological Dissolutions.2010Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Struvite is a salt that is formed out of 

    Mg2+,NH4+ and PO43- and it crystallizes in form of MgNH4PO4.6H2O. Struvite‟s (magnesium ammonium phosphate or MAP) precipitation has recently been regarded as an interesting technique to remove phosphate and ammonium from waste water. The high elimination rates and the possibility of recycling the struvite as a direct slow release fertilizer make this process feasible and appealing. However, the costs due to the raw chemicals needed are drawbacks that leave aside the application of the process in some facilities. The MAP biological dissolution makes possible a recycling of magnesium and phosphate, a fact that reduces the process‟s costs and will help making it even more feasible and environmentally friend. This thesis goes also through the parameters, reactions and different techniques that optimize the struvite precipitation process.

  • 263.
    Faith-Ell, Charlotta
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Suggestions for process improvement for the application of environmental requirements in Swedish road maintenance contracts2005Article in journal (Other academic)
  • 264.
    Faith-Ell, Charlotta
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    The application of environmental requirements in procurement of road maintenance in Sweden2005Doctoral thesis, comprehensive summary (Other scientific)
    Abstract [en]

    The Swedish Road Administration (SRA) is responsible for maintenance of the state-run roads in Sweden. The SRA also has an overarching responsibility for the state of the environment in the road transport sector. The overall aim of this thesis is to examine the implementation of environmental requirements in SRA road maintenance contracts and to develop an improved model for the implementation of environmental requirements, making it easier for the SRA to establish an optimal contracting strategy for routine road maintenance. Using several qualitative methodologies, the thesis is mainly based on a content analysis of 18 tender documents, two case studies consisting of five cases and a questionnaire. The study shows that the SRA have stipulated environmental requirements in procurements of routine road maintenance since 1997. The formulation of the environmental requirements was initially carried out at the Regional Road Management Directorates. However, in the case of trucks and construction vehicles relevant organisations were given the opportunity to actively participate in the development of environmental requirements. The contractors in the study fulfil about three-quarters of the environmental requirements in the contracts. The main reasons for not complying with the environmental requirements are: i) absence of consultation with municipalities and competent authorities, and ii) inadequate communication of environmental requirements to subcontractors. The benefit to the environment of laying down environmental requirements for road maintenance is difficult to assess, due to unclear environmental requirements and the fact that the SRA does not systematically follow up the environmental requirements. The findings of the research indicate that the SRA have made a serious effort to integrate environmental aspects in their maintenance contracts through the use of environmental requirements. However, the SRA need to adopt a more systematic approach towards road maintenance contracts in order to make green procurement an effective tool for environmental adaptation of road maintenance. The thesis proposes an improved process for development, implementation and follow-up of environmental requirements. The proposed process can be summarised in five criteria that need to be fulfilled in order to achieve an environmentally efficient application of environmental requirements: i) the environmental requirements have to be based on legislation, environmental quality objectives, identified environmental problems and/or research, ii) environmental indicators and baselines have to be established in order to facilitate follow-up of compliance with the requirements, iii) the environmental requirements have to be stated clearly in order to limit misinterpretations and to facilitate follow-up, iv) the contractors have to develop working processes, routines and training based on the environmental requirements, v) routines for following-up compliance with the requirements and the environmental effectiveness need to be developed, and there has to be a feedback of the results. Furthermore, the purchasing function needs to be integrated with the implementation of the contracts. Although, having faced several problems during the introduction of environmental requirements, the SRA have managed to meet the main arguments that are used for justification of green procurement. However, if slightly changed, the process of green procurement has the potential of becoming an important tool in the work for enhancing the environmental performance of the SRA.

  • 265.
    Faith-Ell, Charlotta
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Management and Assessment.
    The introduction of a new infrastructure planning system in Sweden: Implications for EIA2012Conference paper (Other academic)
  • 266.
    Faith-Ell, Charlotta
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    The introduction of environmental requirements for trucks and construction vehicles used in road maintenance contracts in Sweden2005In: Corporate Social Responsibility and Environmental Management, ISSN 1535-3958, E-ISSN 1535-3966, Vol. 12, no 2, p. 62-72Article in journal (Refereed)
    Abstract [en]

    This paper examines the development and implementation of environmental requirements for trucks and construction vehicles in Swedish road maintenance contracts. The process in which the road administration involved relevant organizations in the development of a model for emission-based payment for the vehicles was analysed in a participatory study. Intentions behind the requirements were investigated using interviews and questionnaires. The results point to the importance of actively involving, informing and training all relevant parties. Transparency towards sub-contractors and the public is needed to justify the requirements. The payment model, based on environmental performance, is also suggested for use in other types of requirement in road maintenance contracts. To make green procurement an effective policy instrument, the model needs further development, e.g. systematic information, training of clients and contractors, and follow-up of the requirements.

  • 267.
    Faith-Ell, Charlotta
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Balfors, Berit
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Environmental requirements in procurement of road maintenance in Sweden2005Article in journal (Other academic)
  • 268.
    Faith-Ell, Charlotta
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Balfors, Berit
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Folkeson, Lennart
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    The application of environmental requirements in Swedish road maintenance contracts2006In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 14, no 2, p. 163-171Article in journal (Refereed)
    Abstract [en]

    This paper reports two studies of the implementation of environmental requirements in Swedish road maintenance contracts. It aims to examine the fulfillment and follow-up of the requirements, the client intentions behind the requirements, and factors influencing the contractors' environmental performance. The study shows that a serious effort to integrate environmental aspects into the contracts has been made. However, the application of the requirements is hampered by deficient information transfer to key actors and a lack of systematic follow-up of the requirements. In order to make green procurement effective, simpler and clearer requirements and effective follow-up routines are needed.

  • 269.
    Faith-Ell, Charlotta
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Management and Assessment.
    Engelbrektsson, Elina
    Halling, Jon
    Svensson, Jonas
    Where social impact assessment is not required: The Case of Sweden2012Conference paper (Other academic)
  • 270.
    Faith-Ell, Charlotta
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Management and Assessment.
    Kalle, Heikki
    External and internal tiering in Estonia and Sweden2012Conference paper (Refereed)
  • 271.
    Faith-Ell, Charlotta
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Management and Assessment.
    Karlsson, Ann-Kristin
    Viking, Anders
    The relationship between SEA and Breeam Community2012Conference paper (Other academic)
  • 272. Faltmarsch, Rasmus
    et al.
    Osterholm, Peter
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Chemical composition of cabbage (Brassica oleracea L. var. capitata) grown on acid sulfate soils2010In: Journal of Plant Nutrition And Soil Science/Zeitschrift für Pflanzenernahrung und Bodenkunde, ISSN 1436-8730, E-ISSN 1522-2624, Vol. 173, no 3, p. 423-433Article in journal (Refereed)
    Abstract [en]

    The purpose of this study was to investigate the influence of soil geochemistry on the concentrations of Ca, K, Mg, P, Co, Ni, Zn, Mn, Cu, and Fe in cabbage (Brassica oleracea L. var. capitata) grown on acid sulfate (AS) soils in Western Finland. A total of 11 topsoil (0-20 cm) and corresponding cabbage samples and three whole-soil profiles (approximate to 0-260 cm) were collected on three agricultural fields. The concentrations of Co and Zn in cabbage were correlated with the NH4Ac-extractable (easily available) concentrations in the topsoil, indicating that the uptake of these elements in cabbage is largely governed by soil geochemistry. Yet, the concentrations of Co and Zn in cabbage were not in general elevated relative to that of Finnish average values, although some AS soils showed enriched concentrations of these metals in the soil and cabbage. Significant geochemical differences (e.g., oxidation depth, organic-matter and S content, pH) were observed among the studied AS soils, while, on the other hand, the concentrations of Ca, K, Mg, P, Ni, Mn, Cu, and Fe in cabbage were relatively similar. The hydroxylamine-extractable concentrations of these elements in the topsoil were not correlated to those in cabbage, suggesting that uptake is not governed by the oxide-bound fraction of these elements in the soil. Similarly, the easily available concentrations of Ca, P, Ni, Mn, Cu, and Fe in the topsoil were not correlated to those in cabbage, indicating that uptake is independent of the easily available concentrations in the soil. Hence, it is suggested that cabbage can regulate and thus optimize its concentrations of Ca, P, Ni, Mn, Cu, and Fe. Oxidation depth affected neither the easily available concentrations of Co, Ni, Zn, and Mn in the topsoil nor the concentrations in cabbage. However, the subsoil with a lower oxidation depth, which is to a smaller extent affected by leaching, may partly be enriched in these metals. Nevertheless, these showed no increased concentrations in cabbage. Based on these findings, it is suggested that the large amounts of metals mobilized in AS soils are easily lost to drains, subsequently contaminating nearby waterways and estuaries whereas they are only partly enriched in cabbage and other previously studied crops (oat).

  • 273.
    Fatehi Pouladi, Soheil
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Phosphorus Removal from Domestic Wastewater Using Dual Reactive Materials Polonite® and Absol®.2011Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Private wastewater treatment facilities release tons of phosphorus to the aquatic environment due to the insufficient removal efficiency in conventional soil infiltration systems. Reactive filter materials have demonstrated promising P removal rates. Laboratory-scale column experiments were carried out using Absol® and Polonite® in dual infiltration media and results were compared with Polonite® functioning as the only layer of reactive filter material. Two sets of experiments were arranged with layer lengths of 5 cm and 15 cm which were operated for 50 and 119 days respectively. Columns with an additional layer of Absol® demonstrated very good average removal rates of 85.99 % and 99.13 % in both experiments while the effluent in the former exceeded the maximum allowed P concentration shortly after half of the total time of the experiment. On the other hand, O-P concentration in collected samples from dual filter media with 15 cm layers of Absol® and Polonite® (column B1) was as low as 0.04 mg/l after 119 days of operation exhibiting high potentials for Absol® in local wastewater treatment. Levels of pH in treated samples showed a decreasing trend in all columns which was similarly simultaneous with high removal rates observed in B1.

  • 274. Feiccabrino, James
    et al.
    Gustafsson, David
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Physics.
    Lundberg, Angela
    Surface-based precipitation phase determination methods in hydrological models2013In: Hydrology Research, ISSN 1998-9563, Vol. 44, no 1, p. 44-57Article in journal (Refereed)
    Abstract [en]

    We compared solid and liquid precipitation mass output from three categories of common model precipitation phase determination schemes (PPDS) to the recorded precipitation phase in a set of 45 years of 3-hour manual meteorological observations from 19 Swedish meteorological stations. In the first category of rain/snow thresholds, it was found that rain/snow air temperature threshold (ATT) is a better precipitation phase indicator than a rain/snow dew point temperature threshold. When a rain/snow ATT of 0.0 degrees C (a default value used in some recent models) was replaced by 1.0 degrees C, misclassified precipitation was reduced by almost one half. A second category of PPDS use two ATTs, one snow and one rain, with a linear decrease in snow fraction between. This category identified precipitation phase better than a rain/snow ATT at 17 stations. Using all observations from all the meteorological stations, a final category using an air-temperature-dependent snow probability curve resulted in slightly lower misclassified precipitation mass at 13 of the 19 stations. However, schemes from the linear decrease in snow fraction category had the lowest misclassified precipitation mass at four meteorological stations.

  • 275. Feiccabrino, James
    et al.
    Lundberg, Angela
    Gustafsson, David
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Improving surface-based precipitation phase determination through air mass boundary identification2012In: Hydrology Research, ISSN 1998-9563, Vol. 43, no 3, p. 179-191Article in journal (Refereed)
    Abstract [en]

    Most hydrological models apply one empirical formula based on surface air temperature for precipitation phase determination. This approach is flawed as surface precipitation phase results from energy exchanges between falling precipitation and air in the lower atmosphere. Different lower atmospheric conditions cause different precipitation phase probabilities for near-freezing temperatures. Often directly measured lower atmospheric conditions are not available for remote areas. However, meteorological observations occurring before/after similar air mass boundaries have similar atmospheric conditions that vary from most other observations. Therefore, hydrological models can indirectly account for lower atmospheric conditions. Twenty years of manual observations from eight United States weather stations were used to compare misclassified precipitation proportions when analyzing (a) all precipitation observations together and (b) identified cold air mass boundary observations (CAB) and non-CAB observations separately. The CAB observations were identified by a rapid surface air temperature decrease. A two-surface air temperature threshold method with one threshold all snow (T-S degrees C) and one all rain (T-R degrees C) having a linear snow fraction decrease between the thresholds was used. The T-S (0 degrees C), and T-R (4 degrees C) values for CAB were 1 degrees C warmer than for non-CAB (-1 degrees C, 3 degrees C). Analyzing CAB and non-CAB separately reduced misclassified precipitation 23%, from 7.0 to 5.4%.

  • 276. Feng, X. -T
    et al.
    Liu, J.
    Jing, Lanru
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Engineering Geology and Geophysics.
    Research and application on coupled t-h-m-c processes of geological media in china - a review2004In: Coupled Thermo-Hydro-Mechanical-Chemical Processes in Geo-Systems — Fundamentals, Modelling, Experiments and Applications, Elsevier, 2004, no C, p. 37-48Chapter in book (Refereed)
    Abstract [en]

    Theoretical models of coupled T-H-M-C processes of geological media and the associated numerical solutions have become an attractive research focus in geomechanics and related fields in China. This paper provides a systematic overview of the past progress in the fundamental studies of the coupled THM models and numerical methods, and their applications in the fields of oil/gas reservoir, coal mining, and water resources engineering works. The key areas of weakness in research in this field are also outlined and possible directions for the future development are discussed.

  • 277. Fernandez, I
    et al.
    Plaza, Elzbieta
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Water, Sewage and Waste technology.
    Trela, Jozef
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Water, Sewage and Waste technology.
    Hultman, Bengt
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Water, Sewage and Waste technology.
    Mendez, R
    Evaluation of deammonification process by Anammox activity measurement2009In: Proceedings IWA 2nd  Specialized Conference “Nutrient Management in Wastewater Treatment Plants”, 2009, p. 501-508Conference paper (Refereed)
  • 278.
    Fernlund, Joanne M. Robison
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Engineering Geology and Geophysics.
    Tafesse, Solomon
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Engineering Geology and Geophysics.
    Magnusson, Mimmi K.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Engineering Geology and Geophysics.
    Total analysis of till using resistivity and 3D image analysisArticle in journal (Other academic)
  • 279.
    Fernlund, Joanne
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Engineering Geology and Geophysics.
    Tafesse, Solomon
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Engineering Geology and Geophysics.
    Magnusson, Mimmi
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Engineering Geology and Geophysics.
    Lithological analysis of multiple size fractions of tillArticle in journal (Other academic)
  • 280. Fernández, Isaac
    et al.
    Plaza, Elzbieta
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Water, Sewage and Waste technology.
    Trela, Jozef
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Water, Sewage and Waste technology.
    Hultman, Bengt
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Water, Sewage and Waste technology.
    Méndez, Rámon
    Evaluation of Deammonification Process by Response Surface Models2011In: Water, Air and Soil Pollution, ISSN 0049-6979, E-ISSN 1573-2932, Vol. 215, no 1-4, p. 299-309Article in journal (Refereed)
    Abstract [en]

    The influence of the operational variables on the Anammox process has been generally researched considering each variable separately. However, the optimization of the process also requires the identification of the more significant variables and their possible interactions. Response surface models were successfully applied to evaluate the performance of the Anammox process in a deammonification system (i.e., one-stage biofilm Anammox process) taking into account the combined effects caused by two sets of three variables. Specific Anammox activity was measured by a manometric method and used as the response variable. The obtained models pointed out that the significant variables were the temperature, the value of pH, and the ratio between the unionized species of the substrates (free ammonia and free nitrous acid (FA/FNA)). There were interactions among them caused by chemical equilibriums. Total nitrogen concentration and ammonium concentration were found to be not significant in the tested range. According to the models, the optimum values of temperature, pH, and free ammonia to free nitrous acid ratio within the test ranges were, respectively, 30A degrees C, 7.0, and 0.3. Further research at higher temperatures and lower values of pH and FA/FNA ratios would be necessary in order to find the absolute optimum conditions for the process. The obtained model can be also useful in order to develop control strategies that take into account the significant variables and their optimum ranges. A strategy to control deammonification reactors has been proposed, according to the results of the modeling.

  • 281.
    Finnveden, Göran
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Environmental Strategies.
    Toller, Susanna
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Wadeskog, A
    Malmqvist, T
    Carlsson, A
    Environmental Impacts of the building and real estate management sectors2009Conference paper (Refereed)
  • 282. Fiori, A.
    et al.
    Dagan, G.
    Cvetkovic, Vladimir
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630).
    Jankovic, I.
    Tailing of the breakthrough curve in aquifer contaminant transport: Equivalent longitudinal macrodispersivity and occurrence of anomalous transport2008Conference paper (Refereed)
    Abstract [en]

    We analyse the mass arrival (breakthrough curve) at control planes at × of a plume of conservative solute injected at time t = 0 in the plane × = 0. The formation is of random three-dimensional stationary and isotropic conductivity K, characterized by the univariate normal distribution f(Y), Y = lnK, and the integral scale I. The flow is uniform in the mean, of velocity U, and longitudinal transport is quantified by f(z,x), the probability density function (pdf) of travel time r at x. We characterize transport by an equivalent longitudinal macrodispersivity αL(x), which is proportional to the variance of the travel time. If αL is constant, transport is coined as Fickian, while it is anomalous if αL increases indefinitely with x. If f(z,x) is normal (for × I), transport is coined as Gaussian and the mean concentration satisfies an ADE with constant coefficients. For the subordinate structural model transport is anomalous, in spite of the closeness of the conductivity distribution to the lognormal one. To further analyse anomalous behaviour, a relationship is established between the shape of f(K) for K→0 and the behaviour of αL, arriving at criteria for normal or anomalous transport. The model is used in order to compare results with the recent ones presented in the literature, which are based on the Continuous Time Random Walk (CTRW) approach. It is found that a class of anomalous transport cases proposed by CTRW methodology cannot be supported by a conductivity structure of finite integral scale.

  • 283. Fiori, Aldo
    et al.
    Boso, Francesca
    de Barros, Felipe P. J.
    De Bartolo, Samuele
    Frampton, Andrew
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Water, Sewage and Waste technology.
    Severino, Gerardo
    Suweis, Samir
    Dagan, Gedeon
    An indirect assessment on the impact of connectivity of conductivity classes upon longitudinal asymptotic macrodispersivity2010In: Water resources research, ISSN 0043-1397, E-ISSN 1944-7973, Vol. 46, p. W08601-Article in journal (Refereed)
    Abstract [en]

    Solute transport takes place in heterogeneous porous formations, with the log conductivity, Y = ln K, modeled as a stationary random space function of given univariate normal probability density function (pdf) with mean < Y >, variance sigma(2)(Y), and integral scale I-Y. For weak heterogeneity, the above mentioned quantities completely define the first-order approximation of the longitudinal macrodispersivity sigma(L) = sigma I-2(Y)Y. However, in highly heterogeneous formations, nonlinear effects which depend on the multipoint joint pdf of Y, impact alpha(L). Most of the past numerical simulations assumed a multivariate normal distribution (MVN) of Y values. The main aim of this study is to investigate the impact of deviations from the MVN structure upon alpha(L). This is achieved by using the concept of spatial correlations of different Y classes, the latter being defined as the space domain where Y falls in the generic interval [Y,Y + Delta Y]. The latter is characterized by a length scale lambda(Y), reflecting the degree of connectivity of the domain (the concept is similar to the indicator variograms). We consider both "symmetrical" and "non-symmetrical" structures, for which lambda(Y') = lambda(-Y') (similar to the MVN), and lambda(Y') not equal lambda(-Y'), respectively, where Y' = Y - < Y >. For example, large Y zones may have high spatial correlation, while low Y zones are poorly correlated, or vice versa. The impact of lambda(Y) on alpha(L) is investigated by adopting a structure model which has been used in the past in order to investigate flow and transport in highly heterogeneous media. It is found that the increased correlation in the low conductive zones with respect to the high ones generally leads to a significant increase in alpha(L), for the same global I-Y. The finding is explained by the solute retention occurring in low Y zones, which has a larger effect on solute spreading than high Y zones. Conversely, alpha(L) decreases when the high conductivity zones are more correlated than the low Y ones. Dispersivity is less affected by the shape of lambda(Y) for symmetrical distributions. It is found that the range of validity of the first-order dispersivity, i.e., alpha(L) = I-Y sigma(2)(Y), narrows down for non-symmetrical structures.

  • 284. Fiori, Aldo
    et al.
    Jankovic, Igor
    Dagan, Gedeon
    Cvetkovic, Vladimir
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Water Resources Engineering.
    Ergodic transport through aquifers of non-Gaussian log conductivity distribution and occurrence of anomalous behavior2007In: Water resources research, ISSN 0043-1397, E-ISSN 1944-7973, Vol. 43, no 9Article in journal (Refereed)
    Abstract [en]

    Three-dimensional advective transport of passive solutes through isotropic porous formations of stationary non- Gaussian log conductivity distributions is investigated by using an approximate semianalytical model, which is compared with accurate numerical simulations. The study is a continuation of our previous works in which formation heterogeneity is modeled using spherical nonoverlapping inclusions and an approximate analytical model was developed. Flow is solved for average uniform velocity, and transport of an ergodic plume is quantified by mass flux ( traveltime distribution) at a control plane. The analytical model uses a self- consistent argument, and it is based on the solution for an isolated inclusion submerged in homogeneous background matrix of effective conductivity. As demonstrated in the past, this analytical model accurately predicted the entire distributions of traveltimes in formations of Gaussian log conductivity distributions, as validated by numerical simulations. The present study ( 1) extends the results to formations of non- Gaussian log conductivity structures ( the subordination model), ( 2) extends the approximate analytical model to cubical blocks that tessellate the entire domain, ( 3) identifies a condition in conductivity distribution, at the tail of low values, that renders transport anomalous with macrodispersivity growing without bounds, and ( 4) provides links of our work to continuous time random walk ( CTRW) methodology, as applied to subsurface transport. It is found that a class of CTRW solutions proposed in the past cannot be based on solution of flow in formations with conductivity distribution of finite integral scale.

  • 285.
    Folkeson, Lennart
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Kumulativa effekter och konsekvenser: behandling i miljöbedömning och miljökonsekvensbeskrivning för vägar2010Report (Other academic)
    Abstract [en]

    In Swedish transport infrastructure planning, cumulative effects are not given the attention demanded by

    the Swedish Environmental Code and the European so-called SEA and EIA directives (Strategic

    Environmental Assessment and Environmental Impact Assessment, respectively). In the Environmental

    Code, the formulations concerning cumulative effects are vague. The EIA handbook of the Swedish

    Road Administration does not give much guidance. There is thus a great need for development of

    procedures and methods adapted to Swedish road planning.

    The overall aim of the report is to contribute to the development of the treatment of cumulative effects in

    SEA and EIA of road planning in Sweden. Specific aims are to describe the concept of cumulative

    effects and to give advice on approaches and methods that can be used in cumulative effects analysis and

    assessment. The report mainly builds on American and Canadian literature. “Cumulative effects” are

    changes to the environment that are caused by an action or measure together with other past, present and

    future actions and measures.

    The report advices a structured procedure for the description and assessment of cumulative effects. The

    recommended procedure takes ”Valued Ecosystem Components” as its point of departure. VEC are any

    parts of the environment that is considered important by the proponent, public, scientists and authorities

    participating in the assessment procedure. The procedure has five steps: 1) scoping, 2) analysis of effects,

    3) identification of the need for mitigation, 4) evaluation of significance, 5) follow-up. The report gives

    examples of the application of these steps adapted to Swedish road planning.

  • 286.
    Folkeson, Lennart
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Boughedaoui, M
    Joumard, R
    Ortega Pérez, E
    Wäger, P
    Camusso, C
    Pronello, C
    Arapis, G
    Karkalis, K
    Goger, T
    Chiron, M
    Dimopoulou, S
    Assessment of some indicators within an impact2010In: Indicators of environmental sustainability in transport: an interdisciplinary approach to methods / [ed] Joumard, R., Gudmundsson, H., Bron: INRETS , 2010, p. 141-189Chapter in book (Refereed)
  • 287.
    Frampton, Andrew
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Stochastic analysis of fluid flow and tracer pathways in crystalline fracture networks2010Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Understanding groundwater flow systems and how these control transport is an essential part in assessing the suitability of subsurface environments as hosts for storage of toxic waste. Therefore it is important to be able to integrate knowledge obtained from field characterisation of the subsurface with methods which can be used to evaluate and predict possible impact on surrounding environments.In this thesis I investigate the characteristics of flow and transport in discrete fracture networks by analysing Eulerian and Lagrangian descriptions within a stochastic framework. The analysis is conducted through numerical flow and transport simulations configured according to available field data, combined with independent theoretical analytic and semi-analytic methods which are able to reveal insight to relevant constitutive properties. It is shown that numerical simulations conducted with the discrete fracture network approach can be both conditioned and confirmed against field measurable quantities, and the developed theoretical methods are evaluated against results obtained from simulation. Thereby, a methodology which can provide links between field measurable quantities and tracer discharge is presented, developed and evaluated. It is shown to be robust with respect to underlying assumptions used for flow configurations.In particular, a specific sampling algorithm for obtaining a Lagrangian description of transport based on a Eulerian description of flow is proposed, evaluated and shown to be robust for the cases considered, providing accurate replications. Also a generalisation of both the advection-dispersion solution and the one-sided stable distribution is shown to be able to evaluate advective transport quantities, and combined with a Lagrangian retention model it is shown to be a fairly accurate and robust method for upscaling distributions, enabling predictions of transport in terms of tracer discharge. Evaluation of transport is also conducted against the advective-dispersion assumption, where results indicate advective transport is generally non-Fickian for the fracture networks and domain scales considered, but not necessarily anomalous. Additionally, the impact certain model assumptions have on tracer discharge are analysed. For example, transport is evaluated for assumptions regarding injection mode, fracture network heterogeneity, relationship between aperture and transmissivity, relationship between transmissivity and size, as well as scale and modelling dimension. In relation to hydraulic testing and flow analysis, a method for conditioning fracture transmissivity from field measurements of flow by simulation is developed and evaluated against homogenisation assumptions commonly used in field applications. Results indicate the homogenisation assumption generally fails for current interpretations of field data.

  • 288.
    Frampton, Andrew
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Cvetkovic, Vladimir
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Numerical and analytical modelling of advective travel times in realistic three-dimensional fracture networks2011In: Water resources research, ISSN 0043-1397, E-ISSN 1944-7973, Vol. 47, no W02506, p. 16pp-Article in journal (Refereed)
    Abstract [en]

    Travel time distributions obtained from advective transport in multiple realisations of realistic discrete fracture network simulations are analysed using the truncated one-sided stable distribution, which has previously been shown to generalise both the advection-dispersion solution as well as one-sided stable distributions. Using this model it is shown that the Fickian assumption inherent in the advection-dispersion equation generally fails, despite that the first two moments of travel time essentially scale linearly with distance. It is also observed that the equally probable realisations drawn from the ensemble can produce a wide range of behaviour under the current configuration, such that Fickian conditions are almost obtained in some cases for increasing scales. Based on a small-scale calibration against particle breakthrough, the model is then shown to successfully predict limiting bounds of transport for a one order of magnitude increase in scale. Correlation in particle velocity is explicitly shown to be significant for scales close to the characteristic Lagrangian segment length. The network configuration is obtained from extensive site characterisation data at the Laxemar region in Sweden, and represents a block scale domain of reasonably sparse background fractures.

  • 289.
    Frampton, Andrew
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Cvetkovic, Vladimir
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Significance of injection modes and heterogeneity on spatial and temporal dispersion of advecting particles in two-dimensional discrete fracture networks2009In: Advances in Water Resources, ISSN 0309-1708, E-ISSN 1872-9657, Vol. 32, no 5, p. 649-658Article in journal (Refereed)
    Abstract [en]

    We investigate the impact of injection mode (flux and resident injection) and heterogeneity in hydraulic properties on dispersion of advecting particles in two-dimensional discrete fracture network models, using a Monte Carlo method. We find that the injection mode has a significant effect on dispersion: The resident injection mode exhibits anomalous features of transport whereas the flux injection mode tends to Gaussian transport; this observation is easily understood by considering phase diagrams where a limited number of particles entering low velocity fractures greatly increase macrodispersion. In spite of a sizeable portion of negative longitudinal velocities, it is shown that multiple crossings are negligible when quantifying longitudinal macrodispersion. A simple probabilistic expression of particle mass balance is shown to predict well the spatial distribution of advecting particles.

  • 290.
    Frampton, Andrew
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Cvetkovic, Vladimir
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Upscaling particle transport in discrete fracture networks: 1. Nonreactive tracers2007In: Water resources research, ISSN 0043-1397, E-ISSN 1944-7973, Vol. 43, no 10, p. W10428-Article in journal (Refereed)
    Abstract [en]

    We study tracer transport through discrete fracture networks and develop a methodology for upscaling particle breakthrough curves on the basis of fracture segment data. Our prime interest is to model the early arrival and peak of tracer breakthrough curves, i.e., to capture the bulk of the tracer mass arrival. This study is based on two-dimensional discrete fracture network simulations, combined with a truncated one-sided stable distribution as a model for upscaling particle transitions. Results indicate that this model can accurately capture the bulk mass and peak of the breakthrough distributions for an upscaled distance of at least 1 order of magnitude in terms of transport scale, which for our simulations is about 2 orders of magnitude greater than the mean fracture segment scale. We also introduce an accurate mapping algorithm for transforming Eulerian into Lagrangian flow statistics, without a priori knowledge of network connectivity.

  • 291.
    Frampton, Andrew
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Cvetkovic, Vladimir
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Upscaling particle transport in discrete fracture networks:  2. Reactive tracers2007In: Water resources research, ISSN 0043-1397, E-ISSN 1944-7973, Vol. 43, no 10, p. W10429-Article in journal (Refereed)
    Abstract [en]

    We study sorbing tracer transport through discrete fracture networks using astochastic Lagrangian framework, combined with the methodology for upscalingparticle breakthrough curves developed in the first part of this article series.Results indicate that this procedure can accurately predict expected normalizedtracer discharge for an upscaled distance of 1 order of magnitude in terms oftransport scale, which for our simulations is about 2 orders of magnitudegreater than the mean fracture segment scale. Specifically, we show theimportance of retaining the correlation between the water residence time τ andthe hydrodynamic control of retention β in order to make accurate tracerdischarge predictions. Also, we show that the extreme tails of τ and β distributions have essentially no impact on tracer discharge. These results areillustrated using the unlimited diffusion model, and for two hypotheticaltracers with properties designed to capture the behavior of many commonlyoccurring natural radionuclides.

  • 292.
    Frampton, Andrew
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Water Resources Engineering.
    Vladimir, Cvetkovic
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Water Resources Engineering.
    Inference of field scale fracture transmissivities in crystalline rock using flow log measurements2010In: Water resources research, ISSN 0043-1397, E-ISSN 1944-7973, Vol. 46, no 11, p. W11502-Article in journal (Refereed)
    Abstract [en]

    Characterization of transmissivity for crystalline rock is conducted through simulation by conditioning against borehole flow rates obtained from high-resolution, in situ field measurements during extraction pumping. Full three-dimensional discrete fracture network simulations are carried out according to specifications obtained from site characterization data in a stochastic Monte Carlo setting. A novel method of conditioning is thereby introduced and applied using nonparametric comparison tests, which provide quantifiable measures of accuracy enabling evaluation of simulated results against field measurements. The assumption of a constitutive relationship ( perfect correlation) between fracture size and transmissivity is adopted. The method is evaluated against both single and multiple realizations, various domain size, and fracture length configurations and shown to be robust for the cases considered. When the introduced method of conditioning is applied, transmissivity parameterization can be inferred to a narrow range with a quantifiable accuracy in terms of a probability value. Results indicate that elementary interpretation of transmissivity based on homogenization of a porous medium will generally underestimate transmissivity. Further implications on advective transport for natural flow conditions are briefly evaluated, indicating advective breakthrough times can be overestimated up to a factor of about 10 in the median.

  • 293.
    Franzén, Frida
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Creating pathways for stakeholder participation in water management2012Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The role of stakeholder participation has been increasingly recognized as important in water management. The EU Water Framework Directive (WFD), adopted in 2000 requires Member States to fulfill three levels of participation; information, consultation and active involvement. This thesis focuses on the third level of participation; where concernd groups, organizations or individuals are involved in co-designing or co-thinking of water management. This thesis uses case studies in Sweden to explore pathways for stakeholder participation in catchment-based water management, focusing on how the opportunity for stakeholder participation is created; social mechanisms important for responding to change; and how institutional arrangements can generate stakeholder participation. The result of the study shows that opportunities for changing track towards more participatory water management could be triggered by either social and ecological changes or surprises. However, in order to take the opportunity to change, social mechanisms such as leadership and social capital, is crucial. The legacy of institutional arrangements affects how water management adapts to new requirements and surprises. Some old patterns might clash with new approaches of participatory and adaptive water management. The results show the importance of creating links crucial to generate stakeholder participation. Municipalities are important actors in catchment-based water management, as well as bridging organizations that can be seen as independent by participating stakeholders. Based on these results, the solution to realize active involvement of stakeholders suggested by the Swedish Water Authorities is discussed. The result suggests that there are some important challenges to overcome, regarding institutional arrangements that could encourage stakeholder participation in water management.

  • 294.
    Franzén, Frida
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Hammer, Monica
    Balfors, Berit
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Institutional arrangements for stakeholder participation in water management: an analysis of two Swedish catchment areasManuscript (preprint) (Other academic)
    Abstract [en]

    Stakeholder participation has recently become an important part of natural resource management. Several policy documents and legislation acts such as the EU Water Framework Directive (WFD) emphasize the importance of participation for successful implementation. However, only few studies deal with the link between stakeholder participation and institutional arrangements. Therefore, the aim of this paper is to explore the role of changes in institutional arrangements, in order to meet new requirements on stakeholder participation in water management. We use a case study application to explore two neighboring catchment areas in southern Sweden. These areas are interesting since similar management plans of wetland creation by farmers, were suggested in the 1990s, which resulted in different solutions of institutional arrangement and level of stakeholder participation. We study these areas with three checkpoints in time; (i) the initial stage covering the period for the management plans proposal; (ii) approximately ten years after the proposal, meaning that also the WFD had been adopted; and (iii) current development of the institutional arrangement, when the real implementation of the WFD has proceeded. The data collection was based on literature review, interviews and a questionnaire covering questions of collaboration patterns between different stakeholder groups in the catchment areas. The study shows how a new institutional arrangement emerged in one of the catchment areas, where also the proposed management plan was realized. Whereas, in the other area the traditional institutional arrangement continued unchanged, and the management plan was not realized. The comparison of the collaboration patterns in the catchment areas showed great differences; especially concerning municipal collaboration and the role of bridging organizations. The result indicated that bridging organizations could be important in linking farmers and other stakeholder groups, to realize the wetland creation. These results show the importance of institutional change in terms of adapting to ecological or social changes. Also, the results indicate that old water institutions can be an obstacle when new requirements are introduced, such as those following the WFD.

  • 295.
    Franzén, Frida
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Kinell, Gerda
    Walve, Jakob
    Elmgren, Ragnar
    Söderqvist, Tore
    Participatory social-ecological modeling in eutrophication management: the case of Himmerfjärden, Sweden.2011In: Ecology and society, ISSN 1708-3087, Vol. 16, no 4Article in journal (Refereed)
    Abstract [en]

    Stakeholder participation is increasingly seen as central in natural resource management. It is also required bythe European Union Water Framework Directive, which identifies three levels of participation; information, consultation, andactive involvement. In this paper we discuss the active involvement of stakeholders, using our experience from a case study inthe Himmerfjärden region, which is a coastal area southwest of Stockholm, Sweden. Our study used the systems approachproposed by the European Union research project called Science and Policy Integration for Coastal System Assessment(SPICOSA), in which local stakeholders and a study site team constructed an integrated simulation model of a crucial coastalmanagement issue. In this case the issue was nitrogen enrichment. We showed how stakeholder participation in the modelingprocess helped identify interesting and currently relevant management scenarios, and how the modeling process facilitatedcommunication of the likely ecological, economic, and social effects of these scenarios to the stakeholders. In addition,stakeholders also reported social gains in terms of network building. We managed to actively involve local stakeholders in waterissues, and the research process clearly strengthened the social capital in the Himmerfjärden region, and created a basis forfuture collaboration regarding water management. Our experience indicates that the approach we tried is a useful tool forpromoting active stakeholder involvement in water management projects. Also, the results of our science and policy integrationapproach indicated that the study site team assumed a leadership role, which is a commonly recognized factor in successfulnatural resource management.

  • 296.
    Furberg, Dorothy
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Management and Assessment.
    Nilsson, Susanna
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Management and Assessment.
    Langaas, Sindre
    Miljöinformationsenheten, Stockholm, Sweden .
    An indicator-based analysis of the river basin districts established under the EU water framework directive2006In: European Water Management Online, ISSN 1461-6971, p. 1-20Article in journal (Refereed)
    Abstract [en]

    This study gives a first indicator-based assessment of the differences and similarities between the River Basin Districts (RBDs) established under the EU Water Framework Directive (WFD). The RBDs are intended to be the management units for water resources within the EU. Yet, limited harmonized or easily comparable data currently exists for this new administrative level. While there are coordinated efforts to develop a Water Information System for Europe (WISE), there is still a need for making initial and complementary assessments of the RBDs, using a set of identical indicators for all RBDs. The analysis was performed with the help of geographic information systems (GIS) and publicly available spatial databases, environmental monitoring databases and other statistics. A major goal of the study was to rank the RBDs according to the pressure on and status of their water resources. The results show a clear north-south dichotomy and that the most serious water situations occur in Western Europe, although a few regional variations appear for some indicators. The current assessment was limited in terms of the information available and more comprehensive assessments of the RBDs for comparison and policy-making purposes are needed

  • 297.
    Fältmarsch, Rasmus
    et al.
    Åbo Akademi University, Department of Geology and Mineralogy.
    Österholm, Peter
    Åbo Akademi University, Department of Geology and Mineralogy.
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Chemical composition of cabbage (Brassica oleracea L) grown on acid sulphate soils2010In: Journal of Plant Nutrition And Soil Science/Zeitschrift für Pflanzenernahrung und Bodenkunde, ISSN 1436-8730, E-ISSN 1522-2624, Vol. 173, no 3, p. 423-433Article in journal (Refereed)
  • 298. Garrity, N. J.
    et al.
    Battalio, R.
    Hawkes, Peter J.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630).
    Roupe, D.
    Evaluation of event and response approaches to estimate the 100-year coastal flood for pacific coast sheltered waters2007In: Coastal Engineering 2006: Proceedings of the 30th International Conference, 2007, p. 1651-1663Conference paper (Refereed)
    Abstract [en]

    Coastal flooding on the Pacific Coast of the United States typically results from the joint occurrence of relatively high water levels and large waves, which are partially correlated. This paper evaluates three approaches to address the joint probability of water levels and waves (flood forcing events) in estimating coastal flood levels (responses) with a 100-year return period. The event approach involves selecting extreme events that are expected to force a response that approximates or exceeds the 100-year flood response. The two response approaches determine the response probability from a calculated response data set. The approaches were applied to a sheltered waters site to inform the development and implementation of the United States Federal Emergency Management Agency's guidelines for mapping coastal flood hazards on the Pacific Coast. Both event and response approaches can provide adequate results, but each requires varying levels of judgment and has advantages and disadvantages. A hybrid between event and response approaches is identified as a balance of accuracy and efficiency in coastal flood studies.

  • 299.
    Gillefalk, Mikael
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Där Åkerströmmen svämmar över.2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Det går att hävda att Sverige är förskonat från katastrofala översvämningar och med största sannolikhet kommer vi inte behöva uppleva en förödelse såsom den i Pakistan år 2010. Samtidigt finns det belägg för att översvämningar kommer inträffa oftare och bli allt allvarligare i takt med att klimatförändringarna fortgår. I framtiden kommer vi kanske uppleva händelser  såsom den i Arvika år 2000 som mindre extraordinära. I alla lägen behöver vi veta mer om det nuvarande läget för att kunna göra förutsägelser om framtiden.

    Den här studien syftar till att kartlägga det rådande vattenföringsläget i avrinningsområdet Åkerströmmen, norr om Stockholm. Detta genom att undersöka kulvertar och genom att analysera flödesfrekvenser. Resultatet visar att det definitivt finns en problematik kring höga vattenflöden och -nivåer som behöver adresseras. På flera platser hotar vattnet järnväg, enskilda hus, vägar och åkermark. Åtgärder behöver sättas in och ytterligare studier som kopplar samman vattennivåer med konsekvenser är nödvändiga. Samtidigt behöver frågor kring biologisk mångfald utredas parallellt då hög flödeskapacitet och förutsättningar för biologisk mångfald står i konflikt med varandra. En väl upplyst samhällsplanering är viktigt för att ta hänsyn till både ekologiska och hydrologiska effekter av åtgärder i vattendrag.

  • 300.
    Gillefalk, Mikael
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630).
    Lindberg, Felix
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630).
    Sediment State and Flow – An Investigation of Sediment Pollution and Transport in the Bîc River, Republic of Moldova.: A Minor Field Study.2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The Bîc River in the Republic of Moldova is a heavily polluted water body. Along the river stretch, from a small creek in Sipoteni close to the river mouth at Gura Bîcului, sediment samples were taken using a very cost-effective method and analyzed for a number of pollutants. The results showed very high levels of petroleum products in and downstream of the city of Chişinău, situated in the middle of the river basin, ex-ceeding even the guideline value for cleanup of industrial land. Concentrations of heavy metals were detected at all sample points, exceeding the Lowest Effect Level (LEL) in 37 out of 48 samples and the Probable Effect Level (PEL) in four of them. High concentrations of nutrients (N and P) were detected, especially outside of the city, where concentrations exceeded even the Severe Effect Level (SEL) for both N and P at one site. DDT concentrations were highest at the beginning of the river, the concentrations becoming lower and lower when getting closer to the river mouth. At three of the six sampling sites, DDT concentrations exceeded the LEL. PCB levels were lower than the LEL. This was attributed to unsuitable handling of the samples before analysis and therefore the PCB concentration levels requires further investiga-tion. The continued monitoring of the sediments is of great need, therefore a proposal for a monitoring program was written. It was estimated that Bîc contributes 118000 tons of suspended particles to Dniester each year, almost 60 % more per km2 than Dniester contributes to the Black Sea.

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