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  • 101.
    Elmi Mohamed, Abdullahi
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Iman, Hussien M.
    Hydropolitics in the Horn of Africa: Conflicts and Required Cooperation in the Juba and Shabelle River Basins2010In: Shared Waters, Shared Opportunities: Hydropolitics in East Africa, Nairobi: French Institute for Research in Africa , 2010, p. 37-52Chapter in book (Other academic)
  • 102.
    Engström, Emma
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Predicting the transport of Escherichia coli to groundwater2015Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Groundwater contamination with pathogens poses a health risk worldwide. Predictive modeling could provide decision support for risk analysis in this context. This study therefore aimed to improve predictive modeling of the transport of Escherichia coli (E. coli) to groundwater. Primarily, it included a review of the state-of-the-art of the underlying process, influencing factors and modeling approaches that relate to E. coli transport in the unsaturated zone. Subsequently, two recently developed models were innovatively applied to the context of microbial contamination. The Active Region Model was evaluated as an alternative to the traditional, uniform flow model (Richard’s equation) to describe bacterial transport in a wastewater treatment facility. It resulted in removal rates that were two orders of magnitude smaller than the traditional approach, more consistently with observations. The study moreover assessed the relevance of a spatial probit model to estimate the probability of groundwater source contamination with thermotolerant coliforms in a case study in Juba, South Sudan. A conventional probit regression model resulted in spatially auto-correlated residuals, pointing to that the spatial model was more accurate. The results of this approach indicated that the local topography and the near presence of areas with informal settlements (Tukul zones) were associated with contamination. Statistical analyses moreover suggested that the depth of cumulative, long-term antecedent rainfall and on-site hygiene were significant risk factors. The findings indicated that the contributing groundwater was contaminated in Juba, and that contamination could be both local and regional in extent. They are relevant for environments with similar climatic, hydrogeological and socioeconomic characteristics, which are common in Sub-Saharan Africa. The results indicated that it is important to consider spatial interactions in this subject area. There is a need for studies that assess the distance within which such interactions can occur, using both mechanistic and statistical methods. Lastly, the results in this study consistently emphasized the importance of flow patterns for E. coli transport. It is thus recommended that future studies evaluate how models of preferential flow and transport can incorporate microbial fate. The multidisciplinary nature of the subject calls for a systems approach and collaboration between disciplines.

  • 103.
    Engström, Emma
    et al.
    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.
    Mörtberg, Ulla
    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.
    Gaily, Tarig
    Mangold, Mikael
    Prevalence of microbiological contaminants in groundwater sources and risk factor assessment in Juba, South Sudan2015In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 515-516, p. 181-187Article in journal (Refereed)
    Abstract [en]

    In low-income regions, drinking water is often derived from groundwater sources, which might spread diarrheal disease if they are microbiologically polluted. This study aimed to investigate the occurrence of fecal contamination in 147 improved groundwater sources in Juba, South Sudan and to assess potential contributing risk factors, based on bivariate statistical analysis. Thermotolerant coliforms (TTCs) were detected in 66% of the investigated sources, including 95 boreholes, breaching the health-based recommendations for drinking water. A significant association (p<. 0.05) was determined between the presence of TTCs and the depth of cumulative, long-term prior precipitation (both within the previous five days and within the past month). No such link was found to short-term rainfall, the presence of latrines or damages in the borehole apron. However, the risk factor analysis further suggested, to a lesser degree, that the local topography and on-site hygiene were additionally significant. In summary, the analysis indicated that an important contamination mechanism was fecal pollution of the contributing groundwater, which was unlikely due to the presence of latrines; instead, infiltration from contaminated surface water was more probable. The reduction in fecal sources in the environment in Juba is thus recommended, for example, through constructing latrines or designating protection areas near water sources. The study results contribute to the understanding of microbiological contamination of groundwater sources in areas with low incomes and high population densities, tropical climates and weathered basement complex environments, which are common in urban sub-Saharan Africa.

  • 104.
    Engström, Emma
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. KTH, School of Architecture and the Built Environment (ABE), Transport Science.
    Karlström, Anders
    KTH, School of Architecture and the Built Environment (ABE), Transport Science.
    Mörtberg, Ulla
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Mangold, Mikael
    Applying spatial regression to evaluate risk factors for microbiological contamination of urban groundwater sources in Juba, South Sudan2017In: Hydrogeology Journal, ISSN 1431-2174, E-ISSN 1435-0157, Vol. 25, p. 1077-1091Article in journal (Refereed)
    Abstract [en]

    This study developed methodology for statistically assessing groundwater contamination mechanisms. It focused on microbial water pollution in low-income regions. Risk factors for faecal contamination of groundwater-fed drinking-water sources were evaluated in a case study in Juba, South Sudan. The study was based on counts of thermotolerant coliforms in water samples from 129 sources, collected by the humanitarian aid organisation M,decins Sans FrontiSres in 2010. The factors included hydrogeological settings, land use and socio-economic characteristics. The results showed that the residuals of a conventional probit regression model had a significant positive spatial autocorrelation (Moran's I = 3.05, I-stat = 9.28); therefore, a spatial model was developed that had better goodness-of-fit to the observations. The most significant factor in this model (p-value 0.005) was the distance from a water source to the nearest Tukul area, an area with informal settlements that lack sanitation services. It is thus recommended that future remediation and monitoring efforts in the city be concentrated in such low-income regions. The spatial model differed from the conventional approach: in contrast with the latter case, lowland topography was not significant at the 5% level, as the p-value was 0.074 in the spatial model and 0.040 in the traditional model. This study showed that statistical risk-factor assessments of groundwater contamination need to consider spatial interactions when the water sources are located close to each other. Future studies might further investigate the cut-off distance that reflects spatial autocorrelation. Particularly, these results advise research on urban groundwater quality.

  • 105.
    Engström, Emma
    et al.
    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.
    Kulabako, Robina
    Makerere University, Department of Civil Engineering, Kampala, Uganda.
    Balfors, Berit
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Water Transport, Retention, and Survival of Escherichia coli in Unsaturated Porous Media: A Comprehensive Review of Processes, Models, and Factors2015In: Critical reviews in environmental science and technology, ISSN 1064-3389, E-ISSN 1547-6537, Vol. 45, no 1Article, review/survey (Refereed)
    Abstract [en]

    The vadose zone can function as both a filter and a passage for bacteria. This review evaluates when and why either effect will apply based on available literature. It summarizes theories and experimental research that address the related, underlying bacterial attenuation processes, the applied macro-scale modeling approaches, and the influencing factors - including the cell, soil, solution and system characteristics. Results point to that the relative importance of each removal mechanism depends on the moisture content and the solution ionic strength. The limitations of available modeling approaches are discussed. It remains unclear in which contexts these are reliable for predictions. The temporal first-order kinetic Escherichia coli (E. coli) removal coefficient ranges three orders of magnitude, from 10(-4) to 10(-1)/min. Results suggest that this rate depends on the pore-water velocity. Spatial filtration of E. coli increases with slower flow and higher collector surface heterogeneity. It could be insignificant in the case of heavy and sudden infiltration and subsequent transport in preferential flow paths, induced, for example, by plant roots or cracks in clayey soils. Future research thus needs to address transport as an effect of extreme weather events such as droughts and subsequent floods.

  • 106.
    Engström, Iris
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Steady-state hydrogeological modelling in order to investigate groundwater sensitivity.2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Growing regions and tighter zoning in urban areas are pushing the hydrological bal-ances to establish new equilibriums which are causing a stress on the groundwater. Urbanization can affect the groundwater in several ways in which both raising and lowering of groundwater tables are a possibility. Both ways, sudden changes may bring on socioeconomic costs for the unprepared. Hydrogeological modelling creates the possibilities to visualise processes that cannot be seen with the naked eye. By combin-ing knowledge about the studied area from tests and measurements a conceptual model and additionally a numerical model can be created. To study the magnitude groundwater sensitivity to changes in land-cover a hydrogeological model was created using COMSOL multiphysics within the frame of a case study concerning a horse racetrack located in Täby, north of Stockholm. The model was calibrated against known data and was the applied on a future scenario where both the land-use and climate were changed. The outcome of the model showed that hydrogeological mod-elling is sensitive to the amount and quality of the in-data. Several insecurities in the results can be traced back to a lack of base material and by changing one parameter the result of other calibrated parameters would also change. Equifinality could thus be established to be a major issue when performing groundwater modelling. Further studies of relevant data requirements for different model objectives are required.

  • 107. Eriksson, Ann Kristin
    et al.
    Gustafsson, Jon Petter
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. Swedish University of Agricultural Sciences, Sweden.
    Hesterberg, Dean
    Phosphorus speciation of clay fractions from long-term fertility experiments in Sweden2015In: Geoderma, ISSN 0016-7061, E-ISSN 1872-6259, Vol. 241, p. 68-74Article in journal (Refereed)
    Abstract [en]

    Phosphorus (P) losses from agricultural soils constitute a main driver for eutrophication of the Baltic Sea. There is limited knowledge about sorption and release processes of P in these soils, especially concerning the effects of fertilization. In this study, P speciation of the clay fractions from six different soils in long-term fertility experiments in Sweden was investigated by P K-edge XANES spectroscopy. As expected, unfertilized soils had lower concentrations of acid-digestible P compared with fertilized soils. Based on best-fit standards that emerged from linear combination fitting (LCF) of XANES spectra, phosphate sorbed on iron (Fe) (hydr)oxides was a dominant P species in clay fractions from unfertilized soils containing more than 35 mmol kg(-1) of oxalate-extractable Fe. In contrast, P sorbed on aluminum (Al) (hydr)oxides predominated in soils with lower concentrations of oxalate-extractable Fe. A greater proportion of organically bound P was fit for soil samples containing >2% organic carbon. The soils included one calcareous soil for which a greater proportion of P was fit as apatite. After long-term fertilization, P had accumulated mainly as P adsorbed to Al (hydr) oxides according to the XANES analysis. Our research shows that P speciation in fertilized agricultural soils depended on the level of P buildup and on the soil properties.

  • 108. Eriksson, Ann Kristin
    et al.
    Hesterberg, Dean
    Klysubun, Wantana
    Gustafsson, Jon Petter
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. SLU, Sweden.
    Phosphorus dynamics in Swedish agricultural soils as influenced by fertilization and mineralogical properties: Insights gained from batch experiments and XANES spectroscopy2016In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 566, p. 1410-1419Article in journal (Refereed)
    Abstract [en]

    The soil chemistry of phosphorus (P) is important for understanding the processes governing plant availability as well as the risk of environmental losses of P. The objective of this research was to investigate both the speciation and the pH-dependent solubility patterns of P in clayey agricultural soils in relation to soil mineralogy and fertilization history. The study focused on soil samples from six fields that were subjected to different P fertilization regimes for periods of 45 to 57 years. Soil P speciation was analyzed by P K-edge XANES spectroscopy and chemical fractionation, sorption isotherms were constructed, and dissolved P was measured as a function of pH. The XANES fitting results showed that organic P and P adsorbed to Fe and Al (hydr) oxides were common P constituents in all soils. Calciumphosphateswere identified in five of six soil samples. The XANES results also indicated an increase in P adsorbed to Al and to a lesser extent Fe (hydr) oxides as a result of fertilization. Moreover, the fluorescence intensity from the P K-edge XANES analysis was most strongly correlated with HCl-digestible P (r = 0.81***). Consistent with the XANES analysis, laboratory sorption isotherm models showed that the Freundlich sorption coefficient (K-F) was most closely related to oxalate-extractable Al. Greater proportions of Ca phosphate in two of the heavily fertilized soils in combination with enhanced PO4 solubilization upon sample acidification indicated neoformation of Ca-phosphate precipitates. The results for the unfertilized soil samples generally showed a minimum in dissolved PO4 between pH 6.5 and 7.5, with increases particularly at lower pH. This behavior can be explained either by the dissolution of Al-hydroxide-type sorbents or Ca phosphates at lower pH. In fertilized soils, there was no consistent trend in pH-dependent solubilization of P, with a complex relationship to solid-phase speciation. To conclude, inorganic P species changed most dynamically in agricultural clay soils over a period of several decades, and the role of pH in the solubilization of P depended mainly on P fertilization history and the content of reactive Ca phosphates.

  • 109. Eriksson, Ann Kristin
    et al.
    Hillier, Stephen
    Hesterberg, Dean
    Klysubun, Wantana
    Ulén, Barbro
    Gustafsson, Jon Petter
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. Swedish University of Agricultural Sciences, Sweden.
    Evolution of phosphorus speciation with depth in an agricultural soil profile2016In: Geoderma, ISSN 0016-7061, E-ISSN 1872-6259, Vol. 280, p. 29-37Article in journal (Refereed)
    Abstract [en]

    With time, different soil-forming processes such as weathering, plant growth, accumulation of organic matter, and cultivation are likely to affect phosphorus (P) speciation. In this study, the depth distribution of P species was investigated for an agricultural clay soil, Lanna, Sweden. Small amounts of apatite-P was demonstrated in the topsoil whereas the speciation of Pat 70-100 cm depth consisted of approximately 86% apatite according to P K-edge XANES (X-ray absorption near-edge structure) spectroscopy. Because there were only minor differences in bulk mineralogy and texture, these variations in P speciation were interpreted as the result of apatite weathering of the topsoil. Speciation modeling on soil extracts supported this idea: hydroxyapatite was not thermodynamically stable in the top 50 cm of the soil. Apatite was enriched in the bulk soil relative to the clay fraction, as expected during apatite dissolution. Combined results from batch experiments, XANES spectroscopy and X-ray diffraction suggested chemical transformations of the topsoil as a result from accumulation of organic matter and airing from tillage followed by enhanced weathering of apatite, amphiboles, clay minerals, and iron oxides. This caused the formation of poorly crystalline secondary iron and aluminum (hydr)oxides in the topsoil, which retained part of the released P from apatite. Other P was incorporated into organic forms. Furthermore, the results also showed that short-term acidification below the current pH value (below 5.5 in the topsoil and 7.2 in the deeper subsoil) caused significant solubilization of P. This is attributed to two different mechanisms: the instability of Al-containing sorbents (e.g. Al hydroxides) at low pH (in the topsoil), and the acid-mediated dissolution of apatite (the subsoil).

  • 110.
    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.

  • 111.
    Falk, Anders
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Värdet av gröna tak. En samhällsekonomisk konsekvensanalys av sedumtak.2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The cities in Sweden are growing, and so too are the environmental problems that accompany development. Sedum roofs are stormwater management tools that come with many benefits, yet it is uncertain whether or not sedum roofs are in fact an advisable endeavor for society. This study aims to investigate whether sedum roofs in the Stockholm region are a profitable investment for society. A cost-benefit analysis (CBA) has been carried out in the municipality of Huddinge where the net present value of a sedum roof project is sought. The literature of green roof valuation is scarce, and a second aim is therefore to investigate if a reliable CBA can be conducted in an area where available data are limited. The identified benefits of sedum roofs are stormwater retention, air pollution and carbon dioxide removal, noise reduction, reduced outdoor temperature, increased sales value of apartments and increased life time of roof membrane. The costs that occur are an increased investment, spillage of phosphorus and increased maintenance costs. These costs and benefits have, as far as possible, been quantified and translated into monetary values. The greatest cost is that of investment, and the greatest benefit is the increased sales value of the apartments. Results from the CBA show that a sedum roof in the Stockholm region is a profitable investment for society. The sensitivity analysis indicates that these results are reliable. This study has shown that it is possible to conduct a reliable CBA in an area where the literature is scarce if the aim is to investigate whether a project is profitable for society or not, but not if the aim is to investigate how profitable a project is. A further study, in which a greater scale of sedum roof installation is considered, could be valuable. Decision makers, planners and operatives in city planning and the built environment can use the results from this master thesis in their work, as it provides general information about sedum roofs as well as an economic analysis of the investment.

  • 112.
    Falk, Helena
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Accessibility of Water Related, Cultural Ecosystem Services in Stockholm County.2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The concept of ecosystem services is getting more used in planning. One important type of cultural ecosystem services is recreation, which has to be consumed where it is provided in contrast to services that can be transported to the beneficiaries. This creates a demand for users to move to the site of the service, making accessibility an important characteristic of the service. In a sustainable region the access to different services, including recreation, has to be considered in planning.

    With general transit feed specification data available, storing spatial information and time tables for public transport, the possibility to create time table dependent travel time models emerge. This study utilizes a prototype tool for a geographic information system software to create a network model using time tables to calculate travel times between different origins and water related, cultural ecosystem services via the public transport network in Stockholm County, Sweden. This allows for mapping of spatial variation of access within a region, and by combining this with current census data and population forecasts potential visitors to different recreational sites now and in the future can be estimated. By consulting regional planners in the design of the study the results were made useful for the study area Stockholm County as planning support system.

  • 113. Fiori, Aldo
    et al.
    Zarlenga, Antonio
    Gotovac, Hrvoje
    Jankovic, Igor
    Volpi, Elena
    Cvetkovic, Vladimir
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Dagan, Gedeon
    Reply to comment by S. P. Neuman on "Advective transport in heterogeneous aquifers: Are proxy models predictive?''2016In: Water resources research, ISSN 0043-1397, E-ISSN 1944-7973, Vol. 52, no 7, p. 5703-5704Article in journal (Refereed)
    Abstract [en]

    In this Reply we further comment on the main assumptions and the results of our recent manuscript "Advective transport in heterogeneous aquifers: Are proxy models predictive?''

  • 114. Follin, Sven
    et al.
    Stigsson, Martin
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    A transmissivity model for deformation zones in fractured crystalline rock and its possible correlation to in situ stress at the proposed high-level nuclear waste repository site at Forsmark, Sweden2014In: Hydrogeology Journal, ISSN 1431-2174, E-ISSN 1435-0157, Vol. 22, no 2, p. 299-311Article in journal (Refereed)
    Abstract [en]

    The Forsmark site was recently proposed by the Svensk Karnbranslehantering AB (SKB) to serve as the potential site for construction of a future geological repository for spent high-level nuclear fuel at about 470 m depth in fractured crystalline rock. The considerations included, among other things, distance from regionally significant deformation zones with highly strained rock, lithological homogeneity, low hydraulic conductivity, groundwater salinity with an acceptable range, and lack of potential mineral resources. This report describes the calculation of transmissivity of deduced deformation zones at Forsmark and the transmissivity model used in the regional groundwater flow modeling carried out in support of the integrated site description. Besides significant decrease with increasing depth (more than four orders of magnitude over a depth of about 1 km), the calculated transmissivity values also reveal considerable spatial variability along the strikes of the zones, i.e. lateral heterogeneity (more than two orders of magnitude). A hydro-mechanical coupling is discussed, based on presented models for the tectonic evolution and the principal stress tensor. Tentatively, laboratory-scale relationships developed from normal stress experiments on a single fracture in crystalline rock can be used to estimate the maximum values of transmissivity of deduced deformation zones at Forsmark.

  • 115.
    Freitas, Flavio L. M.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Brazilian land use policies and the development of ecosystem services2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Concerns related to global environmental changes due to land use changes have been driving international communities towards more sustainable land use systems. Brazil is a country of global strategic importance in this matter considering that it is the nation with the largest extension of preserved tropical native vegetation, recognised for its ecosystem services and high and unique biodiversity. Expansion of forestry and agriculture is taking place rapidly in Brazil, partly over degraded pastureland, but also over native vegetation. Regulating policies to govern and limit this expansion is crucial to ensure the preservation of the ecosystems services provided by native vegetation.  This thesis aims at improving the understanding of the potential impacts of prevailing public and private policies in the conservation of nature in Brazil. For this end, the Land Use Policy Assessment (LUPA) model was employed to evaluate potential pathways of implementation of the land use policies. Paper 1 evaluated the effects of current private and public command and control regulations in the protection of above-ground carbon stocks, identifying the most relevant stakeholders holding carbon stocks. The findings suggest that about 10% of carbon stocks are unprotected, where other policy instruments based on the market will be mostly required. Paper 2 performed an assessment of the mechanism for offsetting the legal deficit of native vegetation among landholders, evaluating the different offsetting implementation practices and their impacts on nature protection and socio-economic development. The results indicate that the offsetting mechanism may have little or no additional effects on protection of native vegetation and its ecosystem services because most of the offsetting is likely to take place where native vegetation is already protected by current legislations. However, it is viable to maximise environmental and socio-economic returns from the offsetting mechanism.

  • 116.
    Freitas, Flavio L. M.
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Englund, Oskar
    Chalmers University, Energy and Environment.
    Sparovek, Gerd
    University of São Paulo, Soil Dep..
    Berndes, Göran
    Chalmers University, Energy and Environment.
    Guidotti, Vinicius
    d Institute of Agricultural and Forest Management and Certification – Imaflora.
    Mörtberg, Ulla
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Who owns the Brazilian carbon?Manuscript (preprint) (Other academic)
  • 117.
    Freitas, Flavio L. M.
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Guidotti, Vinicius
    d Institute of Agricultural and Forest Management and Certification – Imaflora.
    Sparovek, Gerd
    University of São Paulo, Soil Dep..
    TECHNICAL NOTE: LAND TENURE MAP OF BRAZIL2017Data set
    Abstract [en]

    The land tenure map of Brazil is the result of a collaborative effort between Imaflora, ESALQ/USP’s GeoLab and the Royal Institute of Technology (KTH, Sweden). This georeferenced database covers the entire Brazilian territory, offering an open and public picture of all public and private land holdings in Brazil.

    This land tenure map is an update on previous studies conducted by Professor Gerd Sparovek's team - ESALQ/USP’s GeoLab - (Freitas, Sparovek e Matsumoto, 2016; Sparovek et al., 2010, 2012, 2015) and includes new functionalities and the coding of a routine that allows for the continuous updating of this database developed by Imaflora and KTH-Sweden teams.

  • 118.
    Freitas, Flavio L M
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Mörtberg, Ulla
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Sparovek, Gerd
    University of São Paulo, Soil Dep..
    Additionality of the compensation mechanism of the Brazilian Forest Code2015Conference paper (Other (popular science, discussion, etc.))
  • 119.
    Freitas, Flavio L M
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Mörtberg, Ulla
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Sparovek, Gerd
    University of São Paulo, Soil Dep..
    Towards integrated sustainability assessment of forest bioenergy options in Brazil2015Conference paper (Other (popular science, discussion, etc.))
  • 120.
    Freitas, Flavio L. M.
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Sparovek, Gerd
    University of São Paulo, Soil Dep..
    Hiromiti Matsumoto, Marcelo
    A ADICIONALIDADE DO MECANISMO DE COMPENSAÇÃO DE RESERVA LEGAL DA LEI NO 12.651/2012: UMA ANÁLISE DA OFERTA E DEMANDA DE COTAS DE RESERVA AMBIENTAL2016In: Mudanças no código florestal brasileiro: desafios para a implementação da nova lei / [ed] Ana Paula Moreira da Silva, Henrique Rodrigues Marques and Regina Helena Rosa Sambuichi, Rio de Janeiro: IPEA , 2016, p. 359-Chapter in book (Refereed)
  • 121.
    Freitas, Flavio L. M.
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Sparovek, Gerd
    University of São Paulo, Soil Dep..
    Mörtberg, Ulla
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Silveira, Semida
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Klug, Israel
    Food and Agriculture Organization of United Nations, Nutrition and Food Systems Division.
    Berndes, Göran
    Chalmers University, Energy and Environment.
    Offsetting legal deficits of native vegetation among Brazilian landholders: effects on nature protection and socioeconomic developmentManuscript (preprint) (Other academic)
  • 122.
    Gautier, Jeanne
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Assessment of the mass of pollutant in a soil contaminated with chlorinated solvents.2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The scarcity of housing has led more and more developers to turn to the conversion of former industrial areas into residential areas. Brownfield redevelopment involves the cleanup of contaminated soil to eliminate any health or environmental risk.

    The quantification of the amount of pollutant in soil is essential to carry out an efficient remediation. It involves sampling and analyzing the soil to determine the concentration of pollutant at a finite number of locations. It is therefore necessary to assess the pollutant amount at unknown locations to estimate the pollution for the whole site. The existing methods used by the depollution actors often lead to underestimation or overestimation of the contamination possibly creating environmental, economic and legal issues.

    This study aims to compare different methods to assess the mass of pollutant using data from a site contaminated with chlorinated solvents. The methods comprise currently used methods (Mean 1, Mean 2), simple interpolation methods (Thiessen Polygons, Natural Neighbor, Inverse Distance Weighting) and a method based on a complete geostatistical approach (Conditional Simulations). They are compared to determine the variability of the results obtained with a specific set of data depending on the chosen method.

    The deterministic methods, although easy to apply, will often underestimate the mass of pollutants contained in soil whereas the geostatistical approach can give a more realistic result, but is complex to implement.

  • 123.
    Ghodoosipour, Behnaz
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Simplified Groundwater Modeling Approach for Quaternary Deposits in Laxemar-Simpevarp, Sweden2014In: World Environmental and Water Resources Congress 2014: Water Without Borders - Proceedings of the 2014 World Environmental and Water Resources Congress, American Society of Civil Engineers (ASCE), 2014, p. 312-322Conference paper (Refereed)
    Abstract [en]

    Groundwater is an important source of drinking water in Sweden. Groundwater level, level fluctuations, and flow direction need to be considered when a risk exists for water contamination. This paper presents the results from 3D groundwater modeling in quaternary deposits in a 71 km2 in Laxemar-Simpevarp, 320 km south of Stockholm close to the nuclear power plant Simpevarp. The site is of significant importance due to the risk for groundwater contamination. For this purpose, groundwater modeling system (GMS) was used. The model domain is characterized by a complex geology and large topographic variations. The main objectives were to predict the groundwater heads and flow directions. The modeling was done in two stages. In the first stage, a model was created using five heterogynous layers. However, the model calibration results showed large differences between the simulated and observed values. The complex stratigraphy and existence of thin layers that intersect at some points negatively affected the model performance. In the second stage, the model was simplified by reducing the existing five layers to two layers including a bedrock layer. The optimum values for hydraulic conductivity were derived using the stochastic modeling module. Results from the multilayer model showed flow toward the sea and in the quaternary deposits but not in high elevated rocks. The same results were found for the simplified two layer model in the first layer. Water flow in the second layer can be representative of the water flowing in the bedrock fractures. Results from the simplified model after applying the stochastic modeling method show better agreement between the simulated and observed values in the monitoring wells. The average residual was shown to decrease by 66% in the two-layered model. The 3D groundwater model GMS was successfully applied to the large Laxemar-Simpevarp region. Model simplification by reducing number of layers and including the bedrock beneath the soil proved to be essential for a better model performance. The same idea could be extended to similar groundwater modeling problems.

  • 124.
    Ghodoosipour, Behnaz
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Three dimensional groundwater modeling in Laxemar-Simepevarp guaternary deposits.2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Groundwater is one of the main sources of drinking water in Sweden. Groundwater fluctuations and the detection of flow direction is of significant environmental importance especially when there is a risk for transport of contaminations. The Swedish Nuclear Fuel and Waste Management Company (SKB) has done detailed geotechnical investigations at two potential sites for a final nuclear waste deposition. This report presents the results from groundwater modeling in quaternary deposits in one of these sites.

    A steady state three dimensional groundwater model was developed for a 71 km2 large area in the Laxemar-Simpevarp, 320 km south of Stockholm close to the nuclear power plant Simpevarp. For this purpose, the Groundwater Modelling System (GMS) was used. The model uses finite difference method to solve the partial differential equation for the water movement with constant density through porous medium. The main objectives were to predict the groundwater heads and the flow directions, and to study the water balance. A conceptual model approach was used by creating five heterogynous soil and rock layers. GIS (Geographic Information System) was used to create top and bottom elevation of the layers by interpolating the GIS data. The model was calibrated using observation data in groundwater monitoring wells and the optimum values for recharge and hydraulic values were found. The numerical simulation was done for two different grid sizes (511×316 m2 and 255×158 m2) referred to coarse and fine grid model respectively.

    Results from the multilayer model showed flow towards the sea and in the quaternary deposits but not in high elevated rocks. The water balance in the multilayer model was satisfied in both grid sizes. The 3D groundwater model GMS was successfully applied to the large Laxemar-Simpevarp region. The choice of grid size was studied and better agreements between observed and simulated groundwater heads were found in the finer grid model. Large simulation errors in some of the observation wells can indicate GMS model’s weakness in modelling thin soil layers and large variance in topography.

  • 125. Goldenberg, Romain
    et al.
    Kalantari, Zahra
    Cvetkovic, Vladimir
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Mörtberg, Ulla
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Deal, Brian
    Destouni, Georgia
    Stockholm University.
    Distinction, quantification and mapping of potential and realized supply-demand of flow-dependent ecosystem services2017In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 593, p. 599-609Article in journal (Refereed)
    Abstract [en]

    This study addresses and conceptualizes the possible dependence of ecosystem services on prevailing air and/or water flow processes and conditions, and particularly on the trajectories and associated spatial reach of these flows in carrying services from supply to demand areas in the landscape. The present conceptualization considers and accounts for such flow-dependence in terms of potential and actually realized service supply and demand, which may generally differ and must therefore be distinguished due to and accounting for the prevailing conditions of service carrier flows. We here concretize and quantify such flow-dependence for a specific landscape case (the Stockholm region, Sweden) and for two examples of regulating ecosystem services: local climate regulation and storm water regulation. For these service and landscape examples, we identify, quantify and map key areas of potential and realized service supply and demand, based for the former (potential) on prevailing relatively static types of landscape conditions (such as land-cover/use, soil type and demographics), and for the latter (realized) on relevant carrier air and water flows. These first-order quantification examples constitute first steps towards further development of generally needed such flow-dependence assessments for various types of ecosystem services in different landscapes over the world.

  • 126. Gouttevin, I.
    et al.
    Lehning, M.
    Jonas, T.
    Gustafsson, David
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Mölder, M.
    A two-layer canopy model with thermal inertia for an improved snowpack energy balance below needleleaf forest (model SNOWPACK, version 3.2.1, revision 741)2015In: Geoscientific Model Development, ISSN 1991-959X, E-ISSN 1991-9603, Vol. 8, no 8, p. 2379-2398Article in journal (Refereed)
    Abstract [en]

    A new, two-layer canopy module with thermal inertia as part of the detailed snow model SNOWPACK (version 3.2.1) is presented and evaluated. As a by-product of these new developments, an exhaustive description of the canopy module of the SNOWPACK model is provided, thereby filling a gap in the existing literature. In its current form, the two-layer canopy module is suited for evergreen needleleaf forest, with or without snow cover. It is designed to reproduce the difference in thermal response between leafy and woody canopy elements, and their impact on the underlying snowpack or ground surface energy balance. Given the number of processes resolved, the SNOWPACK model with its enhanced canopy module constitutes a sophisticated physics-based modeling chain of the continuum going from atmosphere to soil through the canopy and snow. Comparisons of modeled sub-canopy thermal radiation to stand-scale observations at an Alpine site (Alptal, Switzerland) demonstrate improvements induced by the new canopy module. Both thermal heat mass and the two-layer canopy formulation contribute to reduce the daily amplitude of the modeled canopy temperature signal, in agreement with observations. Particularly striking is the attenuation of the nighttime drop in canopy temperature, which was a key model bias. We specifically show that a single-layered canopy model is unable to produce this limited temperature drop correctly. The impact of the new parameterizations on the modeled dynamics of the sub-canopy snowpack is analyzed. The new canopy module yields consistent results but the frequent occurrence of mixed-precipitation events at Alptal prevents a conclusive assessment of model performance against snow data. The new model is also successfully tested without specific tuning against measured tree temperature and biomass heatstorage fluxes at the boreal site of Norunda (Sweden). This provides an independent assessment of its physical consistency and stresses the robustness and transferability of the chosen parameterizations. The SNOWPACK code including the new canopy module, is available under Gnu General Public License (GPL) license and upon creation of an account at https://models.slf.ch/.

  • 127. Greger, M.
    et al.
    Bergqvist, C.
    Sandhi, Arifin
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. Stockholm University, Sweden.
    Landberg, T.
    Influence of silicon on arsenic uptake and toxicity in lettuce2015In: Journal of Applied Botany and Food Quality / Angewandte Botanik, ISSN 1613-9216, E-ISSN 1439-040X, Vol. 88, p. 234-240Article in journal (Refereed)
    Abstract [en]

    Lettuce grown in soil is found to contain high concentrations of arsenic (As). This paper investigates the uptake and speciation of As in lettuce as well as the influence of silicon (Si) on As uptake, since Si may decrease it. Lettuce plants were cultivated in nutrient solution containing arsenite or arsenate with or without silicate. The uptake and distribution of As between roots and shoots, As accu-mulation in cell walls, As speciation, and toxic effects on growth were analysed. Results indicate that arsenite was more toxic to lettuce than was arsenate. Silicate decreased arsenate toxicity but had little effect on arsenite toxicity. In contrast, Si decreased arsenite uptake more than arsenate uptake. The concentration of arsenate was higher than that of arsenite in the plants independent of the As species added. When arsenate was added, the As concentration in shoots was half of that in the roots and this distribution did not change with Si addition. When arsenite was added, approximately 10% of As was found in the shoots and 90% in the roots; this pattern changed in the presence of Si, and As became evenly distributed in the plant. In both roots and shoots, approximately 40% of the As was found in the cell wall fraction; when arsenite was added, the presence of Si increased this fraction to 47%, but only in the shoots. The extraction efficiency when analysing the As species was lower in shoots than in roots, especially in the presence of arsenite and Si. The opposite was found for As concentration in pellets after extraction. This indicated variation in the binding strength of arsenite and arsenate between roots and shoots and between Si-and non-Si-treated plants.

  • 128.
    Grishenko, Vitaly
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Energy Efficiency of Tunnel Boring Machines.2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Herrenknecht AG is a German world-leading Tunnel Boring Machines manufacturer showing strong awareness and concern regarding environmental issues. The company supports research on the Energy Efficiency (EE) of their products, aimed at the development of intelligent design for a green Tunnel Boring Machine. The aim of this project is to produce a ’status quo’ report on EE of three types of Tunnel Boring Machines (Hardrock, EPB and Mixshield TBM). In the framework of this research 39 projects are analysed using calculation tools, plotting and statistical functionalities of Excel and Matlab. The findings of this study inter alia confirm the existence of data quality issue and highlight the necessity of data quality control, allow identification of specific distinctions between energy consumption of the three investigated TBM types, and stress the necessity for optimisation of the layout of TBMs energy supply units and main consumers. Moreover the results of the survey suggest that there is a certain energy saving potential, which is achievable by e.g. an adequate selection of the machine type prior to start of a given project and better adjustment of the machines’ layout to the particular local geological environments. An EE implementation strategy, indicating further research needs, is suggested and discussed.

  • 129.
    Gronowski, Adrian
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Effects of uranium mining on groundwater - Geochemical modeling of aqueous uranium speciation due to changing redox conditions.2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    As a consequence of rising uranium prices an interest in Sweden’s U deposits has emerged. This raises the important question of the possible environmental impacts of U mining operations. One of the most significant and serious issues is the contamination of groundwater by U following mining activities. The processes of uranium release and subsequent transport in groundwater is closely tied to its aqueous chemistry i.e. aqueous speciation, adsorption to mineral surfaces and dissolved organic carbon (DOM). The chemical parameters exerting the most control over these processes are pH and redox potential. The redox potential plays a decisive role because it controls the solubility of uraninite, a common uranium mineral and ore in Sweden’s bedrock deposits. Thus, by gaining insight into how changing redox conditions affect uraninite solubility, assessments can be made in order to estimate the extent of uranium transport by groundwater. Therefore the effects of the redox po-tential on U mobility will be examined in this work by means of computer modeling in the geochemical software VISUAL MINTEQ 3.0. The composition of the water used for modeling resembled that of a typical bedrock groundwater of Northern Sweden in the areas above the highest coastline. The simulations were carried out under different redox potentials at different pH levels in the presence of ferrihydrite and DOM to include the effects of U adsorption. The results show that the redox potential at which the uraninite mineral dissolves varies depending on the pH of the groundwater. From pH 4.0 to 7.5 the redox potential at which uraninite oxidizes decreases from 240-250 mV to 50-60 mV. This means higher redox conditions are needed for the dissolution of uraninite at low pH. Additionally, it is further concluded that the adsorption of U to ferrihydrite and DOC is important at pH 5-8 and pH < 7 respectively, which therefore play an important role in controlling the mobility of U in the modeled groundwater.

  • 130.
    Gustafsson, Jon Petter
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Soil chemical behaviour of cadmium pigments from paints2013Report (Other academic)
    Abstract [en]

    A review focusing on the thermodynamic stability and dissolution rates of Cd-containing sulphides and selenides from paints is presented. In the surface horizon of Swedish agricultural soils, cadmium sulphide, CdS(s), and cadmium selenide, CdSe(s), are shown to be thermodynamically unstable. The presence of electron acceptors such as oxygen gas and iron(III) will lead to gradual dissolution of these compounds. The dissolution rate of Cd-containing sulphides is dependent on the amount of crystalline zinc sulphide in contact with the cadmium, as zinc will be dissolved preferentially from a mixed cadmium zinc sulphide mineral. In the absence of crystalline zinc sulphide, Cd will be dissolved completely after 1-3 years. The presence of crystalline zinc sulphide can extend the life span of CdS to 1-2 decades; however, sewage sludge contains mostly amorphous ZnS that will dissolve more quickly. In conclusion, if a time frame of several decades is applied, it is very likely that Cd from Cd pigments has a similar solubility and bioavailability as an easily soluble Cd salt such as cadmium chloride.

  • 131.
    Gustafsson, Jon Petter
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. Swedish University of Agricultural Sciences, Sweden.
    Akram, Muhammad
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Tiberg, Charlotta
    Predicting sulphate adsorption/desorption in forest soils: Evaluation of an extended Freundlich equation2015In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 119, p. 83-89Article in journal (Refereed)
    Abstract [en]

    Sulphate adsorption and desorption can delay the response in soil acidity against changes in acid input. Here we evaluate the use of an extended Freundlich equation for predictions of pH-dependent SO4 adsorption and desorption in low-ionic strength soil systems. Five B horizons from Spodosols were subjected to batch equilibrations at low ionic strength at different pHs and dissolved SO4 concentrations. The proton coadsorption stoichiometry (eta), i.e. the number of H+ ions co-adsorbed for every adsorbed SO42- ion, was close to 2 in four of five soils. This enabled the use of a Freundlich equation that involved only two adjustable parameters (the Freundlich coefficient K-F and the non-ideality parameter m). With this model a satisfactory fit was obtained when only two data points were used for calibration. The root-mean square errors of log adsorbed SO4 ranged from 0.006 to 0.052. The model improves the possibility to consider SO4 adsorption/desorption processes correctly in dynamic soil chemistry models.

  • 132.
    Gustafsson, Jon Petter
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Lumsdon, David G.
    James Hutton Institute, Aberdeen, UK.
    Comment on "Citrate adsorption can decrease soluble phosphate concentration in soils: Results of theoretical modelling'' by Marek Duputel, Nicolas Devau, Michel Brossard, Benoit Jaillard, Davey L. Jones, Philippe Hinsinger and Frederic Gerard (2013)2014In: Applied Geochemistry, ISSN 0883-2927, E-ISSN 1872-9134, Vol. 46, p. 85-89Article in journal (Refereed)
    Abstract [en]

    By use of a multi-site surface complexation model, Duputel et al. (2013) showed that citrate can decrease the solubility of phosphorus in soils, in contrast to what is commonly expected. We have identified several major errors in their model, which put the conclusions in doubt. We argue that major re-evaluation of their modelling approach is needed.

  • 133.
    Gustafsson, Jon Petter
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Persson, I.
    Oromieh, A. G.
    Van Schaik, J. W. J.
    Sjöstedt, Carin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry.
    Kleja, D. B.
    Chromium(III) complexation to natural organic matter: Mechanisms and modeling2014In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 48, no 3, p. 1753-1761Article in journal (Refereed)
    Abstract [en]

    Chromium is a common soil contaminant, and it often exists as chromium(III). However, limited information exists on the coordination chemistry and stability of chromium(III) complexes with natural organic matter (NOM). Here, the complexation of chromium(III) to mor layer material and to Suwannee River Fulvic Acid (SRFA) was investigated using EXAFS spectroscopy and batch experiments. The EXAFS results showed a predominance of monomeric chromium(III)-NOM complexes at low pH (<5), in which only Cr··C and Cr-O-C interactions were observed in the second coordination shell. At pH > 5 there were polynuclear chromium(III)-NOM complexes with Cr···Cr interactions at 2.98 Å and for SRFA also at 3.57 Å, indicating the presence of dimers (soil) and tetramers (SRFA). The complexation of chromium(III) to NOM was intermediate between that of iron(III) and aluminum(III). Chromium(III) complexation was slow at pH < 4: three months or longer were required to reach equilibrium. The results were used to constrain chromium-NOM complexation in the Stockholm Humic Model (SHM): a monomeric complex dominated at pH < 5, whereas a dimeric complex dominated at higher pH. The optimized constant for the monomeric chromium(III) complex was in between those of the iron(III) and aluminum(III) NOM complexes. Our study suggests that chromium(III)-NOM complexes are important for chromium speciation in many environments.

  • 134.
    Gustafsson, Jon Petter
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Tiberg, Charlotta
    SLU.
    Fosfors betydelse för metallers mobilitet i mark2013Report (Other academic)
    Abstract [en]

    The aim with this project was to investigate the role of dissolved phosphate for the adsorption of lead(II), copper(II), cadmium(II) and uranium(VI) onto ferrihydrite and to soils. The methods involved batch studies, EXAFS spectroscopy, and equilibrium modelling. Phosphate was found to significantly enhance the adsorption of all investigated metals onto ferrihydrite. Results obtained so far show that the results are consistent with the formation of ternary surface complexes at low pH, but additional research is required to understand the processes in more detail. Similar enhancements were not observed in soil samples to which phosphate is added, and the reasons for this remain to be fully elucidated. In any case, this research shows that the presence of phosphate may restrict the mobility of many trace metals in environments that contain iron(III) (hydr)oxides.

  • 135.
    Gustafsson, Jon Petter
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Tiberg, Charlotta
    Molybdenum binding to soil constituents in acid soils: An XAS and modelling study2015In: Chemical Geology, ISSN 0009-2541, E-ISSN 1872-6836, Vol. 417, p. 279-288Article in journal (Refereed)
    Abstract [en]

    Despite its importance as a trace element, the binding mechanisms of molybdenum in soils are not well known. In this study, we studied the binding of molybdenum onto selected soil samples, and we used X-ray absorption spectroscopy (XAS) to characterize the coordination of molybdenum on three important environmental sorbents: ferrihydrite (Fh), amorphous aluminium hydroxide (Al(OH)(3)) and fulvic acid. The X-ray near-edge structure (XANES) data showed that the added molybdenum(VI) was not reduced, although for the organic samples the coordination shifted from tetrahedral to octahedral. The EXAFS (extended X-ray absorption fine structure) analysis showed that molybdenum(VI) on Fh and Al(OH)(3) was dominated by edge-sharing bidentate complexes with Mo center dot center dot center dot Fe and Mo center dot center dot center dot Al distances of 2.80 and 2.62 angstrom, respectively. For ferrihydrite, there was a minor contribution from a corner-sharing bidentate complex at 3.55 angstrom. Further, geochemical modelling suggested an additional role of an outer-sphere complex at high pH. A sample from a spodic Bs horizon had XANES and EXAFS features similar to those of Mo sorbed to Al(OH)(3), highlighting the importance of Al(OH)(3)-type sorbents in this soil. However, in the studied organic samples molybdenum(VI) was present in a distorted octahedral configuration as an organic complex. The results were used to improve molybdenum binding reaction equilibrium constants in the CD-MUSIC model for ferrihydrite and in the Stockholm Humic Model. Collectively the results show that acid soils may contain sorbents able to bind molybdenum efficiently, and thus prevent its leaching to waters.

  • 136.
    Haaf, Ezra
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Extremvärdesanalys av grundvattennivåmätserier.2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The ability to calculate the probability of extreme groundwater levels is fundamental, when estimating the risk of hydraulic heave at the bottom of an excavation or landslides triggered by excess pore water pressure. This can be done by fitting historic groundwater level data to probability density functions and extrapolating to certain return levels.

    However, very little research has been done in the field of estimating extreme groundwater level with probability density functions. The design guide (TK-Geo) of the Swedish Transport Administration (Trafikverket) gives a brief description of a method developed in the eighties. It is based on applying well-established hydrological theory to groundwater level time series. In this study, recent research on hydrologic extreme value analysis is applied and used to bring the methods in groundwater up to date. More than 100 long time-series of groundwater data recorded by SGU in the Swedish groundwater network (often used as reference series) are utilized for testing. Established parameter estimation techniques such as Maximum Likelihood Estimation and Probability-Weighted Moments with L-moments are compared and weighed against the traditionally used Method of Moments.

    Swedish research with focus on this topic usually takes advantage of the simplicity of the Block Maxima Approach, while evading the more complex Peaks over Threshold method. These methods are also applied and discussed as to how their use influences the inferences made. Traditionally used statistical distributions such as the Normal, Weibull and Gumbel distributions are compared to the more flexible and presently more popular Generalized Extreme Value distribution and Generalized Pareto distribution. In order to estimate model adequacy a number of goodness-of-fit tests are discussed and implemented, such as the Anderson-Darling test and Kolmogorov-Smirnoff test. This results in a general overview of how to compute return levels for high return periods and which models should be preferred. Fitting probability density distributions requires the data to be independent and identically distributed, a condition, which groundwater level measurements are generally not in accordance with. This is a consequence of the groundwater’s inherent seasonality not only within one year, but also over random numbers of years. Using data with seasonality results in underestimation of extremes and should be avoided. Examples of identification and recommendations for handling this sort of phenomena are given.

  • 137.
    Haenel, Nathalie
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Sandberg, Josefin
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Vattenavtryck i konventionell och ekologisk produktion. En jämförande studie av svenska råvaror i en hamburgare.2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The carbon- and ecological footprint due to human activities has in later years gained more attention. In the Swedish media however the water footprint is not as commonly heard of. The definition of a water footprint is the amount of water consumed within the different steps of production of goods and services, the embedded water in the final product or service.

    There are different methods to calculate the water consumption and water footprint in production in order to measure environmental impact from a water perspective. During the early 21st century Hoekstra and Hung (2002) introduced the concept of water footprint and in 2010 a global standard was published.

    This study means to calculate and analyze the water footprint of a conventional and organically produced hamburger, with the aim to quantify and compare the relative importance of different production steps focusing on the beef. To evaluate the ineffective processes and the calculation method as well as critically review data are also part of the purpose.

    Two specific farms have been examined to achieve site specific data on conventional and organic meat production. Some results from previous official publications have been used to fill in data in order to enable analysis of a complete hamburger.

    The result shows that the water footprint of the conventional hamburger is approximately half of the organic one, with the same results showing regarding the ground beef. In both cases the water footprint of the vegetables constitutes about 5 % of the total.

    Calculating the water footprint is a complicated process with many parameters to consider. The selection of data is crucial due to errors in data accumulating in every step of the calculating process. Ever though the method is a simplification of reality we conclude that the results are pointing to the importance of a higher awareness of the environmental impact of meat consumption.

  • 138.
    Haile, Hilab
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Improving Solid Waste Management in Addis Ababa, Ethiopia. Based on the experience from Sweden, Östersund Municipality.2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Lack of genuine concern for solid waste management practices and inefficiency of sol-id waste management system is one of the greatest environmental issues in Addis Ab-aba, Ethiopia. The Current Municipal Solid Waste Management System is extremely inefficient and ineffective. An illegal waste dumping, inefficient waste collection, and informal recycling are some of the issues that need to be immediately rectified. There-fore, this study was conducted in order to get a knowledge transfer from a developed country, Sweden, Östersund Municipality. The practical waste management and recy-cling activities undertaking in the city of Östersund have been assessed, evaluated and discussed in the study. Physical site visits, surveys, informal interviews, and group dis-cussions have also been conducted to be able to draw an immensely useful and tangi-ble recommendation for the improvement of Solid Waste Management and Recycling Scheme in Addis Ababa. Based on the experience acquired from Östersund the entire Solid Waste Management system in Addis Ababa has been evaluated and useful dis-cussions, recommendations, and conclusions have been drawn. Besides as recycling is one of the most significant waste management hierarchy components, it should have been given top priority in reducing the amount of waste generation in developing countries like Ethiopia. However, the recycling activities taking place in the country are highly limited and informal. Moreover, evaluation of the potential of recyclable wastes in Addis Ababa, discussion on how and why recycling needs to be given prece-dence and later comparison is made with Östersund Municipality in order to be able to gain knowledge from the Swedish experience. Besides, discussions were made in order to address decisive measures that need to be taken to implement the Swedish experience in the Solid Waste Management and Recycling sector in Addis Ababa Ethiopia in an environmentally friendly and economical way.

  • 139.
    Halder, Dipti
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Biswas, Ashis
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Slejkovec, Zdenka
    Chatterjee, Debashis
    Nriagu, Jerome
    Jacks, Gunnar
    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.
    Arsenic species in raw and cooked rice: Implications for human health in rural Bengal2014In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 497, p. 200-208Article in journal (Refereed)
    Abstract [en]

    This study compares the concentrations of total and different species of arsenic (As) in 29 pairs of raw and cooked rice samples collected from households in an area of West Bengal affected by endemic arsenicism. The aim is to investigate the effects of indigenous cooking practice of the rural villagers on As accumulation and speciation in cooked rice. It is found that inorganic As is the predominant species in both raw (93.8%) and cooked rice (88.1%). Cooking of rice with water low in As (<10 mu g L-1) significantly decreases the total and inorganic As content in cooked rice compared to raw rice. Arsenic concentration is mainly decreased during boiling of rice grains with excess water. Washing of rice grains with low As water has negligible effect on grain As concentration. The study suggests that rice cooking with low As water by the villagers is a beneficial risk reduction strategy. Despite reductions in As content in cooked rice because of cooking with low As water, the consumption of cooked rice represents a significant health threat (in terms of chronic As toxicity) to the study population.

  • 140.
    Halder, Dipti
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Biswas, Ashis
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Šlejkovec, Zdenka
    Chatterjee, Debashis
    Nriagu, Jerome
    Jacks, Gunnar
    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.
    Variation of arsenic species in raw and cooked rice: Implications for human health in rural BengalManuscript (preprint) (Other academic)
  • 141. Hallberg, M.
    et al.
    Renman, Gunno
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Byman, L.
    Svenstam, G.
    Norling, M.
    Treatment of tunnel wash water and implications for its disposal2014In: Water Science and Technology, ISSN 0273-1223, E-ISSN 1996-9732, Vol. 69, no 10, p. 2029-2035Article in journal (Refereed)
    Abstract [en]

    The use of road tunnels in urban areas creates water pollution problems, since the tunnels must be frequently cleaned for traffic safety reasons. The washing generates extensive volumes of highly polluted water, for example, more than fivefold higher concentrations of suspended solids compared to highway runoff. The pollutants in the wash water have an affinity for particulate material, so sedimentation should be a viable treatment option. In this study, 12 in situ sedimentation trials were carried out on tunnel wash water, with and without addition of chemical flocculent. Initial suspended solids concentration ranged from 804 to 9,690 mg/L. With sedimentation times of less than 24 hours and use of a chemical flocculent, it was possible to reach low concentrations of suspended solids (< 15 mg/L), PAH (< 0.1 mu g/L), As (< 1.0 mu g/L), Cd (< 0.05 mu g/L), Hg (< 0.02 g/L), Fe (< 200 mu g/L), Ni (< 8 mu g/L), Pb (< 0.5 mu g/L), Zn (< 60 mu g/L) and Cr (< 8 mu g/L). Acute Microtox (R) toxicity, mainly attributed to detergents used for the tunnel wash, decreased significantly at low suspended solids concentrations after sedimentation using a flocculent. The tunnel wash water did not inhibit nitrification. The treated water should be suitable for discharge into recipient waters or a wastewater treatment plant.

  • 142.
    Hamisi, Rajabu
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Simulations of water balance conditions and cli-mate variability for Sustainable Agriculture and Energy in the Lower Rufiji Basin.2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This study provides a long-term understanding of the impact of climate varia-bility and land use on seasonal water balance conditions for sustainable agricul-ture development, hydropower generation and ecosystem stability in the Lower Rufiji Basin. The severity of soil drought, extreme flooding and salinity intru-sion in the lower Rufiji floodplains are currently increasing smallholder poverty and enhance the sensitivity on the natural wetlands for shifting farming and livestock pastures. The CoupModel and SWAT hydrological model were ap-plied to assess and compare the impact of climate variability on the water bal-ance. The monthly river discharge was used for calibrating and validating the runoff at the Stiegler's Gorge. The simulated results for water balance compo-nents at Stiegler's Gorge showed 55% of accumulated precipitation is lost through evapotranspiration and 42 % is river runoffs for downstream agricul-ture and ecosystem services. The evaluation of the models simulation perfor-mance and posterior distribution of parameter behavioral value indicates the (GLUE) calibration method in the CoupModel agreed satisfactory with the Bayesian calibration (BC). The minimal variance in the Bayesian Calibration posterior parameter distribution was observed in the parameter for regulating water uptake from (CritThresholDry) and soil moisture availability for soil evaporation(PsiRs_ip). The SWAT simulation showed that south of the central floodplains has high risk of soil drought. The overall assessment implies that drought and river runoff dynamics in the LRB is affected by upstream land use activities. The strategies for building smallholder resilience towards climate change and land use impact requires collective and coordinated water manage-ment actions powered by individual, institutional, financial and technological adaptation.

  • 143.
    Hamisi, Rajabu
    et al.
    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.
    Thunvik, Roger
    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.
    Hamerlynck, O
    Duvail, S
    Applications of Process Base Models for Sustainable Water Utilizations in a Competing Demands and Climate Variability: A Case of the Lower Rufiji, Tanzania2013Conference paper (Refereed)
  • 144.
    Hamisi, Rajabu
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. SEED-KTH.
    Renman, Gunno
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. SEED-KTH.
    Brokking Balfors, Berit
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. SEED-KTH.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. SEED-KTH.
    A new modelling approach for phosphorus mobility and retention processes in the Oxundaån catchment, SwedenManuscript (preprint) (Other academic)
    Abstract [en]

    Eutrophication is the most significant threat towater quality in the entire Baltic Sea region. Its causes are nutrientover-enrichment from diffuse and point sources. Thematic strategies forsustainable mitigation of phosphorus loss from sewage drainage systems andrunoffs from arable land require a holistic approach to identify the criticalpolluting sources and implement relevant policy for adaptive water qualitymanagement. The use of constructed wetlands constitutes one such strategy thatcan mitigate phosphorus loss. However, insufficient understanding about phosphorusmobility and retention in catchments significantly hinders efforts to identifysuitable sites for constructed wetlands and implement alternative, adaptive andeffective management actions. This study aims to evaluate the long-termphosphorus mobility and retention in the Oxudaån catchment in Sweden, andthereby propose suitable sites to localize constructed wetlands. The Soil andWater Assessment watershed model was applied to map and quantify the phosphorusloading from diffuse and point sources under the scenarios of land usemanagement practices. Simulation results have demonstrated the positivecorrelation between the phosphorus concentration with the surface runoffs andnegative correlation with the pH. Overall, Oxundaån catchment indicates a decreasingtrend of phosphorus loading in the Verkaån and Oxundaån riverine of around 2.1% and 1.3 % per year, respectively. The present study suggests the suitablesites for localizing constructed wetlands in the south-west and north-east ofOxundaån lake based on the factor of low slope topography and soilpermeability. The simulation results from the SWAT model offer evidence thatcan guide the localization and choice of management interventions to achieve asustainable mitigation of phosphorus loss. This study concludes that, while singlemanagement actions can help solve the problem of eutrophication, a moreeffective and sustainable mitigation of eutrophication will require the integrationof multiple adaptive land use management approaches.

  • 145.
    Hamisi, Rajabu
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. SEED-KTH.
    Renman, Gunno
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. SEED-KTH.
    Brokking Balfors, Berit
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. SEED-KTH.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. SEED-KTH.
    Welin, Anders
    SWECO International AB, Stockholm, Sweden.
    Larm, Thomas
    Modelling phosphorus recovery by reactive adsorbent in a vertical subsurface flow constructed wetlandManuscript (preprint) (Other academic)
    Abstract [en]

    Phosphorus removal efficiencies by four low - costsreactive adsorbent media were evaluated in the long - time period using thethree - dimensional model of the vertical subsurface flow constructed wetlandsin the COMSOL Multiphysics® software. Evaluations were made for Polonite,Filtralite P, Sorbulite and Wollastonite adsorbent media with the aims ofpredicting their long - term sorption capacity and describing the phenomena ofsorption mechanisms when applied in the vertical subsurface flow constructedwetlands for wastewater purification. The 3D model of the vertical flowconstructed wetlands were dimensioned to Swedish EPA guidelines for small scalewastewater treatment, and calibrated at saturated media using the breakthroughdata derived from the column experiments of similar adsorbent mediaapplication, and the local sensitivity analysis were performed for waterquality and hydraulic loading parameters. It was observed that the breakthroughcurves developed by model were significantly correlated to the experimentaldata. The overall findings showed that Polonite® could be the potentialreactive adsorbent for phosphorus removal in the VF-CWs application, and itsremoval efficiency was discovered to last for 5 years. The large variation ofmedia sorption capacities discovered to be affected more by factor of pH andhydraulic loading rates than the particle size. High degree of predictionaccuracy which is demonstrated by this model suggest that the proposed model isa useful tool for predicting pollutants removal in various reactive porousmedia.

  • 146.
    Hamisi, Rajabu
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. SEED-KTH.
    Renman, Gunno
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. SEED-KTH.
    Herrmann, Inga
    Department of Civil, Environmental and Natural Resources Engineering.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. SEED-KTH.
    Reactive transport modelling of long-term phosphorus dynamic in the compact constructed   wetland using COMSOL MultiphysicsIn: Ecological Engineering JournalArticle in journal (Other academic)
    Abstract [en]

    A three-dimensional reactive transport model (RETRAP-3D) was developed by this study in the COMSOL Multiphysics®software to evaluate the long-term sorption capacity and mechanisms of dissolved reactive phosphorus removal in reactive adsorbent. The model coupledphysics interfaces for water flow, transport of reactive species, reaction kinetics for chemical compositions and biofilm development. Simulations were conducted for Polonite®, Filtralite P®, and Blast Furnace Slag mediaat fully saturated media, equilibrium miscible solution and isothermal heat transfer conditions. The model was validated using column experimental data ofsimilar media for application in constructed filter beds. The general modelling results showed good agreement with the measured breakthrough data. The most significant DIP retention capacity (P < 0.02) and longest residence time(1250 days) has been found for Polonite® and the most insignificant DIP retention for blast furnace slag (P > 0.54). The DIP removal was significantly correlated to factors of pH change, media characteristics, hydraulic dosage and retention times. These results demonstrate the reliability of the model as aflexible tool to predict the long-term performance of filter media and better understand processes within the system under various operational, weather and wastewater conditions.

  • 147. Hammer, Monica
    et al.
    Persson, Klas
    Jarsjö, Jerker
    Petersson, Mona
    Balfors, Berit
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Dinnétz, Patrik
    Mörtberg, Ulla
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Balancing ecosystem services in local and regional water governance: A case study from Lake Mälaren catchment, Sweden2016Conference paper (Refereed)
  • 148.
    Hansson, Caroline
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Miljökvalitetsnormer för vatten i det kommunala detaljplanearbetet - Viktiga faktorer, svårigheter och möjligheter.2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    With the goal of high quality recipients within the European Union the European Water Framework Directive (WFD; 2000/60/EC) was initiated in the year of 2000. In order to achieve water of high quality, goals have been established under the definition of Environmental Quality Standards (EQS). These are defined for lakes, rivers and other water bodies within each municipality. The EQS are defined as a level that are to be reached until a defined year. The EQS are to be kept in mind when zoning is carried out within a municipality. Zoning allows for strategic use of land and water within the municipality and is an important part in the work of achieving the EQS. If a zoning plan does not meet the EQS the plan should not be adopted. The county government should audit plans before they are approved to make sure the chance of reaching the EQS are not hindered by the plan.

    The aim of this study is to investigate which important factors that come into play when a zoning plan is created that will meet the EQS. The aim is also to get an understanding of the work from the municipalities perspective as well as from the viewpoint of the county government. Both the overall perspective and the more detailed field of assessing the impact from a zoning plan is to be analyzed. In the end the goal is to give an overview of how the work is done today, which difficulties that are experienced as well as improvements that could be needed. The study is focused upon the county governments within the North Baltic Sea basin and the municipalities within Stockholm county. Semi-structured interviews and a literature review were conducted followed by a survey study in order to address the research questions. The survey study was directed towards the county governments and municipalities within the geographical study area mentioned above.

    From the methods described above data was collected which resulted in the identification of important steps in the process of making zoning with consideration of the EQS. Also difficulties connected to each phase were identified. The work of follow-up and monitoring was found only to be carried out to a limited extent but is believed to support several important functions in the work, if improved. The impact assessment of zoning on water quality and EQS was found to be one of the more difficult parts of the work with the WFD. Foremost, this process is connected to many uncertainties in the method of calculation but also due to limited data available in some cases. Information needed is for example the current water quality and the levels of pollution connected to different land uses of the area.

    More developed guidelines and support from central authorities was requested by several participants of the survey. Hopefully the Water authorities’ planned action program for the next 6-year work cycle, will result in this. However, more investigations and studies are needed in order to improve and minimize uncertainties in the methods used to calculate impact from zoning on water quality. More education and cooperation between municipalities, county governments and agencies with issues connected to implementing the WFD is needed as well. Overall more consensus is needed in how the work can be carried out while meeting both environmental and societal goals.

  • 149. He, H.
    et al.
    Jansson, Per-Erik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Svensson, Magnus
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Meyer, A.
    Klemedtsson, L.
    Kasimir, Å.
    Factors controlling Nitrous Oxide emission from a spruce forest ecosystem on drained organic soil, derived using the CoupModel2016In: Ecological Modelling, ISSN 0304-3800, E-ISSN 1872-7026, Vol. 321, p. 46-63Article in journal (Refereed)
    Abstract [en]

    High Nitrous Oxide (N2O) emissions have been identified in hemiboreal forests in association with draining organic soils. However, the specific controlling factors that regulate the emissions remain unclear. To examine the importance of different factors affecting N2O emissions in a spruce forest on drained organic soil, a process-based model, CoupModel, was calibrated using the generalized likelihood uncertainty estimation (GLUE) method. The calibration also aims to estimate parameter density distributions, the covariance matrix of estimated parameters and the correlation between parameters and variables information, useful when applying the model on other peat soil sites and for further model improvements. The calibrated model reproduced most of the high resolution data (total net radiation, soil temperature, groundwater level, net ecosystem exchange, etc.) very well, as well as cumulative measured N2O emissions (simulated 8.7±1.1kgN2Oha-1year-1 (n=97); measured 8.7±2.7kgN2Oha-1year-1 (n=6)), but did not capture every measured peak. Parameter uncertainties were reduced after calibration, in which 16 out of 20 parameters changed from uniform distributions into normal distributions or log normal distributions. Four parameters describing bypass water flow, oxygen diffusion and soil freezing changed significantly after calibration. Inter-connections and correlations between many calibrated parameters and variables reflect the complex and interrelated nature of pedosphere, biosphere and atmosphere interactions. This also highlights the need to calibrate a number of parameters simultaneously. Model sensitivity analysis indicated that N2O emissions during growing seasons are controlled by competition between plants and microbes for nitrogen, while during the winter season snow melt periods are important. Our results also indicate that N2O is mainly produced in the capillary fringe close to the groundwater table by denitrification in the anaerobic zone. We conclude that, in afforested drained peatlands, the plants and groundwater level have important influences on soil N availability, ultimately controlling N2O emissions.

  • 150. He, Hongxing
    et al.
    Jansson, Per-Erik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Svensson, Magnus
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Bjorklund, Jesper
    Tarvainen, Lasse
    Klemedtsson, Leif
    Kasimir, Asa
    Forests on drained agricultural peatland are potentially large sources of greenhouse gases - insights from a full rotation period simulation2016In: Biogeosciences, ISSN 1726-4170, E-ISSN 1726-4189, Vol. 13, no 8, p. 2305-2318Article in journal (Refereed)
    Abstract [en]

    The CoupModel was used to simulate a Norway spruce forest on fertile drained peat over 60 years, from planting in 1951 until 2011, describing abiotic, biotic and greenhouse gas (GHG) emissions (CO2 and N2O). By calibrating the model against tree ring data a "vegetation fitted" model was obtained by which we were able to describe the fluxes and controlling factors over the 60 years. We discuss some conceptual issues relevant to improving the model in order to better understand peat soil simulations. However, the present model was able to describe the most important ecosystem dynamics such as the plant biomass development and GHG emissions. The GHG fluxes are composed of two important quantities, the spruce forest carbon (C) uptake, 413 g C m(-2) yr(-1) and the decomposition of peat soil, 399 g C m(-2) yr(-1) . N2O emissions contribute to the GHG emissions by up to 0.7 g N m(-2) yr(-1), corresponding to 76 g C m(-2) yr(-1) . The 60-year old spruce forest has an accumulated biomass of 16.0 kg C m(-2) (corresponding to 60 kg CO2 m(-2)). However, over this period, 26.4 kg C m(-2) (97 kg CO2 eq m(-2)) has been added to the atmosphere, as both CO2 and N2O originating from the peat soil and, indirectly, from forest thinning products, which we assume have a short lifetime. We conclude that after harvest at an age of 80 years, most of the stored biomass carbon is liable to be released, the system having captured C only temporarily and with a cost of disappeared peat, adding CO2 to the atmosphere.

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