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  • 1.
    Abhishek, Sarabjot
    et al.
    Dr BR Ambedkar Natl Inst Technol, Dept Phys, GT Rd Bye Pass, Jalandhar 144027, Punjab, India..
    Kaur, Sarabjot
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Mehra, Rohit
    Dr BR Ambedkar Natl Inst Technol, Dept Phys, GT Rd Bye Pass, Jalandhar 144027, Punjab, India..
    Estimation of Uranium and Related Health Risks Due to Consumption of Groundwater in Lower Himalayas2023In: Indian Journal of Pure & Applied Physics, ISSN 0019-5596, E-ISSN 0975-1041, Vol. 61, no 6, p. 478-483Article in journal (Refereed)
    Abstract [en]

    Exposure to uranium via ingestion of edible products may lead to serious health hazards when taken in quantities more than recommended limit. Hence, to assess the uranium content in groundwater and concerned health hazards 64 groundwater samples were collected from Hamirpur and Mandi districts of Himachal Pradesh. The samples were collected in pre monsoon season from the handpumps and bowries. The region lies in Lower Himalayan range which is storehouse of various granatic rocks. Presence of uranium deposits in Tileli (Mandi), Rajpura (Una), Lambehra (Hamirpur) makes the area more vulnerable for the study. The groundwater samples were analysed to measure concentration of uranium using LED Fluorimeter developed by Quantalase Private. Limited. The uranium concentration in groundwater samples varied from 0.25 to 17.29 & mu;g L-1, with an average value of 1.97. Uranium concentration in none of the samples surpassed the limit of 30 & mu;g L-1 recommended by WHO(2011), 60 & mu;g L-1 set by AERB(2004). Health risks were estimated in terms radiological and chemical toxicity for different isotopes of uranium. The calculated average mortality and morbidity risks were lower than the actual prescribed limit. The average Lifetime Average Daily Dose (LADD) was calculated as 0.04 and Hazard Quotient (HQ) below unity. Annual ingestion doses for different age groups were also measured which lies under safe limit. Thus, it is recommended that the groundwater is safe for consumption by public. Using Hair Compartment Model for uranium and mean daily uranium intake of 2.71 & mu;g for 60-year exposure period, organ specific doses due to uranium radioisotopes in prime organs/tissues and excretion rates via urine, faeces and hair pathway are estimated.

  • 2. Abiye, T. A.
    et al.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Arsenic concentration in groundwater: Archetypal study from South Africa2019In: Groundwater for Sustainable Development, ISSN 2352-801X, Vol. 9, article id 100246Article in journal (Refereed)
    Abstract [en]

    South Africa does not have significant surface water resources, which is often easily affected by unpredictable and rapidly changing climatic variables, due to its location in the arid and semi-arid climatic setting. In large part of the country, groundwater from weathered and fractured crystalline rocks plays pivotal role in sustaining the livelihood, often it contains toxic metals released from the host rocks. The host rocks that are responsible for arsenic release in groundwater are primarily enriched due to metamorphism and igneous processes that resulted in the enrichment of economic minerals. Preliminary assessment indicates that the main arsenic containing minerals are arsenopyrite (FeAsS), arsenical oxide, sulpharsenide, arsenopyritical reefs, leucopyrite, löllingite (FeAs2) and scorodite (FeAsO4·2H2O). Owing to the release of arsenic from highly mineralized rocks that constitute the aquifers, arsenic concentration in the groundwater reaches up to 253 μg/L (Namaqualand), 6150 μg/L (west of Johannesburg), about 500 μg/L in the Karoo aquifers, considerably higher than the WHO guideline value of 10 μg/L. Acid mine drainage from coal and gold mining is also found to be an important source of arsenic and other toxic metals in groundwater.

  • 3.
    Adem Esmail, Blal
    et al.
    Department of Civil, Environmental, and Mechanical Engineering, University of Trento, Via Mesiano 77, Trento, 38123, Italy.
    Geneletti, Davide
    Department of Civil, Environmental, and Mechanical Engineering, University of Trento, Via Mesiano 77, 38123 Trento, Italy.
    Design and impact assessment of watershed investments: An approach based on ecosystem services and boundary work.2017In: Environmental impact assessment review, ISSN 0195-9255, E-ISSN 1873-6432, Vol. 62, p. 1-13Article in journal (Refereed)
    Abstract [en]

    Watershed investments, whose main aim is to secure water for cities, represent a promising opportunity for large-scale sustainability transitions in the near future. If properly designed, they promote activities in the watershed that enhance ecosystem services while protecting nature and biodiversity, as well as achieving other societal goals. In this paper, we build on the concepts of ecosystem services and boundary work, to develop and test an operative approach for designing and assessing the impact of watershed investments. The approach is structured to facilitate negotiations among stakeholders. Its strategic component includes setting the agenda; defining investment scenarios; and assessing the performance of watershed investments as well as planning for a follow-up. Its technical component concerns data processing; tailoring spatially explicit ecosystem service models; hence their application to design a set of “investment portfolios”, generate future land use scenarios, and model impacts on selected ecosystem services. A case study illustrates how the technical component can be developed in a data scarce context in sub-Saharan Africa in a way that is functional to support the steps of the strategic component. The case study addresses soil erosion and water scarcity-related challenges affecting Asmara, a medium-sized city in Eritrea, and considers urban water security and rural poverty alleviation as two illustrative objectives, within a ten-year planning horizon. The case study results consist in spatially explicit data (investment portfolio, land use scenario, impact on ecosystem services), which were aggregated to quantitatively assess the performance of different watershed investments scenarios, in terms of changes in soil erosion control. By addressing stakeholders' concerns of credibility, saliency, and legitimacy, the approach is expected to facilitate negotiation of objectives, definition of scenarios, and assessment of alternative watershed investments, ultimately, to contribute to implementing an adaptive watershed management.

  • 4.
    Agha Karimi, Armin
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Geodesy and Satellite Positioning.
    Internal Variability Role on Estimating Sea Level Acceleration in Fremantle Tide Gauge Station2021In: Frontiers in Earth Science, E-ISSN 2296-6463, Vol. 9, article id 664947Article in journal (Refereed)
    Abstract [en]

    Low frequency internal signals bring challenges to signify the role of anthropogenic factors in sea level rise and to attain a certain accuracy in trend and acceleration estimations. Due to both spatially and temporally poor coverage of the relevant data sets, identification of internal variability patterns is not straightforward. In this study, the identification and the role of low frequency internal variability (decadal and multidecadal) in sea level change of Fremantle tide gauge station is analyzed using two climate indices, Pacific Decadal Oscillation (PDO) and Tripole Interdecadal Pacific Oscillation (TPI). It is shown that the multidecadal sea level variability is anticorrelated with corresponding components of climate indices in the Pacific Ocean, with correlation coefficients of -0.9 and -0.76 for TPI and PDO, respectively. The correlations are comparatively low on decadal time scale, -0.5 for both indices. This shows that internal variability on decadal and multidecadal scales affects the sea level variation in Fremantle unequally and thus, separate terms are required in trajectory models. To estimate trend and acceleration in Fremantle, three trajectory models are tested. The first model is a simple second-degree polynomial comprising trend and acceleration terms. Low passed PDO, representing decadal and interdecadal variabilities in Pacific Ocean, added to the first model to form the second model. For the third model, decomposed signals of decadal and multidecadal variability of TPI are added to the first model. In overall, TPI represents the low frequency internal variability slightly better than PDO for sea level variation in Fremantle. Although the estimated trends do not change significantly, the estimated accelerations varies for the three models. The accelerations estimated from the first and second models are statistically insignificant, 0.006 +/- 0.012 mm yr(-2) and 0.01 +/- 0.01 mm yr(-2), respectively, while this figure for the third model is 0.018 +/- 0.011 mm yr(-2). The outcome exemplifies the importance of modelling low frequency internal variability in acceleration estimations for sea level rise in regional scale.

  • 5.
    Agha Karimi, Armin
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Geodesy and Satellite Positioning.
    Bagherbandi, Mohammad
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Geodesy and Satellite Positioning. Univ Gävle, Fac Engn & Sustainable Dev, Gävle, Sweden..
    Horemuz, Milan
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Geodesy and Satellite Positioning.
    Multidecadal Sea Level Variability in the Baltic Sea and Its Impact on Acceleration Estimations2021In: Frontiers in Marine Science, E-ISSN 2296-7745, Vol. 8Article in journal (Refereed)
    Abstract [en]

    Multidecadal sea level variation in the Baltic Sea is investigated from 1900 to 2020 deploying satellite and in situ datasets. As a part of this investigation, nearly 30 years of satellite altimetry data are used to compare with tide gauge data in terms of linear trend. This, in turn, leads to validation of the regional uplift model developed for the Fennoscandia. The role of North Atlantic Oscillation (NAO) in multidecadal variations of the Baltic Sea is also analyzed. Although NAO impacts the Baltic Sea level on seasonal to decadal time scales according to previous studies, it is not a pronounced factor in the multidecadal variations. The acceleration in the sea level rise of the basin is reported as statistically insignificant in recent studies or even decelerating in an investigation of the early 1990s. It is shown that the reason for these results relates to the global warming hiatus in the 1950s-1970s, which can be seen in all eight tide gauges used for this study. To account for the slowdown period, the acceleration in the basin is investigated by fitting linear trends to time spans of six to seven decades, which include the hiatus. These results imply that the sea level rise is accelerated in the Baltic Sea during the period 1900-2020.

  • 6.
    Agha Karimi, Armin
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Geodesy and Satellite Positioning.
    Ghobadi-Far, Khosro
    Department of Geosciences, Virginia Tech, Blacksburg, VA, United States.
    Passaro, Marcello
    Deutsches Geodätisches Forschungsinstitut der Technischen Universität München, Munich, Germany.
    Barystatic and steric sea level variations in the Baltic Sea and implications of water exchange with the North Sea in the satellite era2022In: Frontiers in Marine Science, E-ISSN 2296-7745, Vol. 9, article id 963564Article in journal (Refereed)
    Abstract [en]

    Satellite altimetry, satellite gravimetry, and in-situ subsurface salinity and temperature profiles are used to investigate the total, barystatic, and steric sea level variations in the Baltic Sea, respectively. To estimate the steric sea level, the density variations are weighted in deeper layers to prevent overestimation of their contribution. We show that the sum of barystatic and steric components exhibits excellent cross correlation (0.9) with satellite altimetry sea level variations and also explains up to 84% of total signal variability from 2002 to 2019. Considering the dominance of barystatic sea level variations in the basin and the limitation of satellite gravimetry in resolving the mass change in water-land transition zones (known as the leakage problem), the mismatch is likely attributed to the inadequate accuracy of the barystatic datasets. The total sea level and its contributors are further decomposed into seasonal, interannual, and decadal temporal components. It is shown that despite its insignificant contributions to seasonal and interannual changes, the steric sea level plays an important role in decadal variations. Additionally, we show that the interannual variations of the barystatic sea level are governed by the North Atlantic Oscillation in the basin. The sea level variation in the North Sea is also examined to deduce the water exchange patterns on different time scales. A drop in the North Sea level can be seen from 2005 to 2011 which is followed by the Baltic Sea level with a ~3-year lag, implying the outflow from the Baltic Sea to the North Sea.

  • 7.
    Ahlberg, Jesper
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Physics.
    Gustafsson, David
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Physics.
    Distributed snow modelling integrating ground penetrating radar data for improved runoff predictions in a Swedish mountain basin2009In: EGU General Assembly 2009, 2009Conference paper (Other academic)
    Abstract [en]

    Operational forecasts of snow melt runoff in Sweden are currently running with precipitation and temperature as the main input variables and calibrated with runoff data, and there is an interest to make better use of new measurement systems for distributed snow data. At the same time, various data assimilation techniques are becoming more frequently used in hydrological modeling, in order to reduce uncertainties related to both model structure errors and errors in input and calibration data. Thus, it is important to address not only what type of snow data that can be used to improve the model predictions, but also what type of input data and model structures that are optimal in relation to the available snow data. The objective of this study is to investigate to what extent the runoff predictions can be improved by assimilation of temporal and spatially distributed snow data, and if the improvements depend on the choice of model structures, for instance the use of energy balance or day-degree snow models. In order to achieve these objectives a new distributed snow model has been implemented into the hydrological modeling framework HYSS/HYPE. This model can easily be setup with either an energy balance model or a day-degree model for the snow pack calculations, and it is easy to run the model with different spatial resolutions. In the fully distributed case, snow drift processes are implicitly included in the model through a precipitation distribution model, based on topographical information and wind direction. The model was applied to a mountain basin in northern Sweden used for hydropower production, where extensive snow measurements were taken during the last two winters 2007-2009. A climate station is located at the outlet of the regulation lake, including automated point measurements of snow depth, snow mass (snow pillow), snow wetness and snow temperature. Distributed snow cover data was sampled using ground-penetrating radar from snow mobiles. Measurements were taken at the time of the maximum snow cover, providing a data set with snow depth, snow density, snow water equivalent along 20 km long transects in representative areas of the basin. The precipitation distribution model was calibrated using the distributed SWE data from the GPR measurements. Application of the calibrated model to previous years without available snow data show that the runoff predictions was improved compared to calibrations without the distributed snow data, however the improvements were larger for the energy balance compared to the day-degree model. Further developments will include assimilation of the temporal and spatial snow data to adjust the distribution of various input variables, for instance air temperature and wind speed.

  • 8.
    Ahlberg, Jesper
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Physics.
    Gustafsson, David
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Physics.
    Snow melt runoff simulations using ensemble Kalman filter assimilation of distributed snow data2010Conference paper (Other academic)
  • 9.
    Ahmad, Arslan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering. SIBELCO Ankerpoort NV, Op Bos 300, NL-6223 EP Maastricht, Netherlands.;Wageningen Univ & Res WUR, Dept Environm Technol, Droevendaalsesteeg 4, NL-6708 PB Wageningen, Netherlands..
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Global Groundwater: Source, Scarcity, Security and Solutions2021In: Groundwater for Sustainable Development, ISSN 2352-801X, Vol. 15, article id 100605Article, book review (Other academic)
  • 10. Ali, S.
    et al.
    Shekhar, S.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Verma, G.
    Chandrasekhar, T.
    Chandrashekhar, A. K.
    Elevated fluoride in groundwater of Siwani Block, Western Haryana, India: A potential concern for sustainable water supplies for drinking and irrigation2018In: Groundwater for Sustainable Development, ISSN 2352-801X, Vol. 7, p. 410-420Article in journal (Refereed)
    Abstract [en]

    Groundwater pollution is a serious health concern in north-western India. In this study, we have reported very high concentration of fluoride i.e. 18.5 and 16.6 mg/l from Sainiwas locality in Siwani block of Bhiwani district, Haryana, India. The values are much higher than the permissible limit set by WHO and BIS. The evapotranspiration in the area leads to Ca2+ precipitation, which allows an increase in F- content in the groundwater. In addition, the replacement of hydroxyl of secondary clay mineral under alkaline condition is responsible for release of F-. In absence of alternative source, the fluoride polluted groundwater in some of these localities is also used for drinking. Further, the suitability of groundwater for irrigation is also evaluated by various parameters such as Sodium Adsorption Ratio (SAR), Sodium Percentage (Na%), Kelly's Ratio (KR), Magnesium Hazard (MH) and Residual Sodium Carbonate (RSC). It emerges out that in a few localities, groundwater is not suitable for irrigation and with respect to Magnesium Hazard (MH) almost all samples are unsuitable for irrigation. This article highlights groundwater quality of Siwani block in Haryana and proposes for immediate remedial measures. 

  • 11. Al-Yaarubi, A. H.
    et al.
    Pain, C. C.
    Grattoni, C. A.
    Zimmerman, Robert W.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Navier-Stokes Simulations of Fluid Flow Through a Rock Fracture2013In: Dynamic Fluids and Transport Through in Fractured Rock, American Geophysical Union (AGU), 2013, p. 55-64Chapter in book (Other academic)
    Abstract [en]

    A surface profilometer was used to measure fracture profiles every 10 microns over the surfaces of a replica of a fracture in a red Permian sandstone, to within an accuracy of a few microns. These surface data were used as input to two finite element codes that solve the Navier-Stokes equations and the Reynolds equation, respectively. Numerical simulations of flow through these measured aperture fields were carried out at different values of the mean aperture, corresponding to different values of the relative roughness. Flow experiments were also conducted in casts of two regions of the fracture. At low Reynolds numbers, the Navier-Stokes simulations yielded transmissivities for the two fracture regions that were closer to the experimental values than were the values predicted by the lubrication model. In general, the lubrication model overestimated the transmissivity by an amount that varied as a function of the relative roughness, defined as the standard deviation of the aperture divided by the mean aperture. The initial deviations from linearity, for Reynolds numbers in the range 1-10, were consistent with the "weak inertia" model developed by Mei and Auriault for porous media, and with the results obtained computationally by Skjetne et al in 1999 on a two-dimensional self-affine fracture. In the regime 10 < Re < 40, both the computed and measured transmissivities could be fit very well to a Forchheimer-type equation, in which the additional pressure drop varies quadratically with the Reynolds number.

  • 12. Amiri, V.
    et al.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. iversity of Southern Queensland, Toowoomba, QLD 4350, Australia.
    Nakhaei, M.
    The hydrogeochemical evaluation of groundwater resources and their suitability for agricultural and industrial uses in an arid area of Iran2021In: Groundwater for Sustainable Development, ISSN 2352-801X, Vol. 12, article id 100527Article in journal (Refereed)
    Abstract [en]

    The hydrogeochemical and quality status of groundwater resources in Yazd province, the central plateau of Iran, has been investigated. The most common water type, followed by chemical facies in this study area, is Cl type (with 50.46%) and Na–Cl facies (47.71%), respectively. Besides, the most samples with industrial and agricultural uses show the Cl type and Na–Cl hydrochemical facies. The position of samples on the Gibbs and van Wirdum diagrams indicate that the water-rock interaction and dissolution of evaporites are the main controlling process of water chemistry. Distribution of samples based on Na/Cl vs. EC, Ca + Mg vs. SO4 + HCO3, and Na–Cl vs. Ca + Mg–SO4–HCO3 highlight the significant role of direct ion exchange in water chemistry change. The water quality for agricultural use is assessed based on some indices including EC, Na%, sodium absorption ratio (SAR), residual sodium carbonate (RSC), magnesium absorption ratio (MAR), permeability index (PI), Kelly's ratio (KR), and Wilcox diagram. In general, the water quality for irrigation purposes is mainly excellent to permissible. The water quality assessment for industrial purposes is performed using some indices including Langelier Saturation Index (LSI), Ryznar Stability Index (RSI), Larson-Skold Index (L-SI), Puckorious scaling index (PSI), and total hardness (TH). Based on these indices, most groundwater samples have mild to high potential to corrode the equipment and pipelines.

  • 13.
    Amiri, Vahab
    et al.
    Department of Geology, Faculty of Science, Yazd University, Yazd, Iran.
    Li, Peiyue
    School of Water and Environment, Chang’an University, No. 126 Yanta Road, Xi’an, 710054, China Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of the Ministry of Education, Chang’an University, No. 126 Yanta Road, Xi’an, 710054, China.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering. KWR Water Cycle Research Institute, Groningenhaven 7, 3433 PE, Nieuwegein, The Netherlands.
    Nakhaei, Mohammad
    Department of Applied Geology, Faculty of Earth Science, Kharazmi University, Tehran, Iran.
    Mercury pollution in the coastal Urmia aquifer in northwestern Iran: potential sources, mobility, and toxicity2021In: Environmental Science and Pollution Research, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 28, no 14, p. 17546-17562Article in journal (Refereed)
    Abstract [en]

    The concentration of total dissolved mercury (HgT) in surface and groundwater resources in the coastal parts of Urmia aquifer (NW of Iran) was investigated to identify the possible sources and sinks of mercury and the geochemical mechanisms controlling its mobilization. The distribution of water samples on the Piper diagram demonstrates that most samples have the Ca-Mg-HCO3 facies. From 62 water samples collected in this area, one sample contained HgT concentrations exceeding the maximum contaminant level recommended by the WHO (6 μg/L). The principal component analysis (PCA) produced five principal components. The positive moderate correlation of HgT with EC, Cl, K, Mg, and Na indicated that the weathering of geological formations was one of the main sources of mercury in groundwater samples. Position of water samples in Eh-pH regions where microorganisms involved in mercury methylation and mineralization were potentially active demonstrated that the aquifer had undergone sulfate reduction and had reached the final stage of the terminal electron accepting process (TEAP) sequence in the methane production processes which are limited to only 37% of the water samples that have anaerobic conditions. Some Hg-bearing species are in nonequilibrium geochemical conditions. The supersaturation of water samples with magnetite and goethite indicated that these Fe-bearing minerals could act as the strong reducing agents for the reduction of Hg(II) to Hg(0).

  • 14.
    Anamaghi, Sara
    et al.
    Faculty of Civil Engineering, K. N. Toosi University of Technology, Tehran, Iran.
    Behboudian, Massoud
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering. School of Civil Engineering, College of Engineering, University of Tehran, Tehran, Iran.
    Mahjouri, Najmeh
    Faculty of Civil Engineering, K. N. Toosi University of Technology, Tehran, Iran.
    Kerachian, Reza
    School of Civil Engineering, College of Engineering, University of Tehran, Tehran, Iran.
    A resilience-based framework for evaluating the carrying capacity of water and environmental resources under the climate change2023In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 902, article id 165986Article in journal (Refereed)
    Abstract [en]

    This paper proposes a new framework for evaluating water and environmental resources carrying capacity (WERCC) based on the concept of resilience under uncertainty. First, several quantitative and qualitative criteria based on the seven principles of resilience and the Pressure-Support-State (PSS) framework are defined to incorporate the positive and negative impacts of human interventions and natural factors on water resources and the environment. The resilience principles include redundancy and diversity, managing connectivity, managing slow variables and their feedbacks, fostering complex adaptive system (CAS) thinking, encouraging learning, broadening participation, and promoting polycentric governance. After evaluating the values of the criteria and sub-criteria using a two-point evidential reasoning (TPER) approach and considering the existing uncertainties, the monthly time series of WERCC with uncertainty bands are calculated. The proposed methodology is then used to evaluate the WERCC in the Zarrinehrud river basin in Iran for a given historical period (1991–2012), and the period of 2020 to 2049 under different climate change scenarios. The results of this analysis demonstrate the inadequacy of the WERCC during the historical period and indicate that the continuation of the existing trend (base scenario, MSC0) will cause many environmental issues. Hence, several water and environmental resources management (WERM) scenarios are proposed to enhance the WERCC. These scenarios are evaluated using a multi-agent-multi-criteria decision-making method to identify the preferable WERM scenario (MSC12356). This scenario, which encompasses various projects (e.g., development and enhancement of water transfer networks and upgrading cultivation methods), improves the average value of the WERCC by 26 %. The results of the proposed methodology are compared with those of a traditional decision-making method, which considers three criteria of average WERCC, the pressure-support index, and the implementation cost. The results demonstrate that the multi-agent-multi-criteria decision-making approach provides a more cost-effective management scenario, with 30 % less cost, leading to only 3 % less carrying capacity.

  • 15.
    Andersson, Edwin
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Gulding, William
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Högvattenföring ochriskbedömning i svensk miljö2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The focus of this paper is on the changing conditions in the hydrological flow of the upper half of Pite älv in Northern Sweden as a consequence of the changes that comes with global warming. This was done by modelling the water flow with the HBV-96 model as its basis which then ran four different scenarios based on predictions for how the climate will have changed by year 2100. The paper also discusses the limitations with this applied method.

    The study found that in the case of dam failure the owner is responsible for the damages, furthermore the owner is recommended to model potential limitations and dangers, but there is no requirement for this. State actors which oversees and keep tabs on all issues regarding water safety exists for every county, though their involvement appear somewhat limited and does not extend to close monitoring of the dams.

    The study found a decrease in the volume of spring floods due to a decrease in snow storage because of increasing temperatures. Furthermore, the increase in mean temperature has no notable direct effect on the autumn precipitation and water flow but potential indirect consequences are discussed. If precipitation were to increase during autumn as predicted, we will see an increase in both the peaks and amount of autumn high flows. However, these peaks will be lower than the current spring floods. We conclude that in large there is no reason for large changes in how the hydro industry conducts itself in relation to regulation of water flow in terms of infrastructure. There is however, possibly a need to increase the margin which one can store water in dams during longer periods with high flow together with more reliance on meteorological short term analysis to be better prepared for more sudden high flows.

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  • 16. Bazilian, Morgan
    et al.
    Rogner, Holger
    Howells, Mark
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Hermann, Sebastian
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Arent, Douglas
    Gielen, Dolf
    Steduto, Pasquale
    Mueller, Alexander
    Komor, Paul
    Tol, Richard S.J.
    Yumkella, Kandeh K.
    Considering the energy, water and food nexus: Towards an integrated modelling approach2011In: Energy Policy, ISSN 0301-4215, E-ISSN 1873-6777, Vol. 39, no 12, p. 7896-7906Article in journal (Refereed)
    Abstract [en]

    The areas of energy, water and food policy have numerous interwoven concerns ranging from ensuring access to services, to environmental impacts to price volatility. These issues manifest in very different ways in each of the three "spheres", but often the impacts are closely related. Identifying these interrelationships a priori is of great importance to help target synergies and avoid potential tensions. Systems thinking is required to address such a wide swath of possible topics. This paper briefly describes some of the linkages at a high-level of aggregation - primarily from a developing country perspective - and via case studies, to arrive at some promising directions for addressing the nexus. To that end, we also present the attributes of a modelling framework that specifically addresses the nexus, and can thus serve to inform more effective national policies and regulations. While environmental issues are normally the 'cohesive principle' from which the three areas are considered jointly, the enormous inequalities arising from a lack of access suggest that economic and security-related issues may be stronger motivators of change. Finally, consideration of the complex interactions will require new institutional capacity both in industrialised and developing countries.

  • 17.
    Behboudian, Massoud
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Anamaghi, Sara
    Faculty of Civil Engineering, K. N. Toosi University of Technology, Tehran, Iran.
    Kerachian, Reza
    School of Civil Engineering, College of Engineering, University of Tehran, Tehran, Iran.
    Kalantari, Zahra
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Comparison of three group decision-making frameworks for evaluating resilience time series of water resources systems under uncertainty2024In: Ecological Indicators, ISSN 1470-160X, E-ISSN 1872-7034, Vol. 158, article id 111269Article in journal (Refereed)
    Abstract [en]

    This study compared three uncertainty-based decision-making frameworks (considering/not considering the hierarchical structure of stakeholders) using resilience-based indices for evaluating different water resources management (WRM) scenarios under the impacts of climate change. The first step involved identifying significant stakeholders in the study area and establishing their relative weights. In the next step, stakeholders were asked to evaluate the management scenarios in the three different decision-making frameworks based on their decision criteria (nine resilience-based indices, implementation cost, and employment). Different types of weights (explicit and interval) were assigned to each stakeholder and their decision criteria, to account for the uncertainty associated with estimating their respective weights. This methodology was applied to the case of the Zarrinehrud River basin in northwest Iran. The best management scenario identified (MSC1346) was able increase lake elevation by 2.6 m (from 1271.3 m to 1273.9 m), improve the resilience of the system by 25 %, and enhance provisioning ecosystem services such as water and food supply and regulating services such as air quality. Comparing the results of the three decision-making frameworks revealed that the two which considered the hierarchical structure of stakeholders were more effective in determining the best scenario. The best scenario selected in the framework that ignored the hierarchical structure of stakeholders (MSC13567) had USD 202 million higher overall implementation and construction costs and gave a negligible difference in resilience value (0.04 difference) compared with scenario MSC1346.

  • 18.
    Behboudian, Massoud
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. Univ Tehran, Coll Engn, Sch Civil Engn, Tehran, Iran..
    Anamaghi, Sara
    K N Toosi Univ Technol, Fac Civil Engn, Tehran, Iran..
    Mahjouri, Najmeh
    K N Toosi Univ Technol, Fac Civil Engn, Tehran, Iran..
    Kerachian, Reza
    Univ Tehran, Coll Engn, Sch Civil Engn, Tehran, Iran..
    Enhancing the resilience of ecosystem services under extreme events in socio-hydrological systems: A spatio-temporal analysis2023In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 397, p. 136437-, article id 136437Article in journal (Refereed)
    Abstract [en]

    Due to the adverse impacts of severe droughts on various aspects of human life and ecosystem services (ESs), the spatio-temporal assessment of the resilience of ESs under droughts is essential. In this paper, we propose a new methodology for assessing ESs-based resilience, taking into account the seven resilience principles: a) redun-dancy and diversity, b) managing connectivity, c) managing slow variables and their feedback, d) complex adaptive system (CAS) thinking, e) experimentation and learning, f) broadening participation, and g) polycentric governance. These principles enable us to consider the main social, political, hydrological, economic, and environmental aspects concerning resilience which have been overlooked in previous studies. The methodology is evaluated by applying it to Zarrinehroud River Basin (ZRB) in north-western Iran. A set of qualitative and quantitative criteria and their sub-criteria are proposed for quantifying the ES-based resilience and generating time series of resilience against severe droughts in several sub-basins in the study area. To evaluate the criteria and sub-criteria, the required data are derived from calibrated SWAT and MODSIM models as well as experts' judjments. The time series of ES-based resilience under 128 Water and Environmental Resources Management (WERM) scenarios (for enhancing agricultural practices, altering and modernizing irrigation methods, improving irrigation network and drainage facilities) and Climate Change (CC) scenarios (RCP 4.5, RCP6.0, and RCP 8.5) are derived for each sub-basin based on short-term (2020-2049) and long-term (2020-2098) periods. The low resilience values (0.53-0.6) of all sub-basins under the base management scenario (the status quo scenario (SC0)) illustrate the need for implementing some projects to enhance the ESs in the study area. The results show that the WERM scenario SC12346 can improve the values of the resilience criterion in sub-basins up to 0.85 and reduce the vulnerability of the study area to droughts. By evaluating all management scenarios, scenario SC12346 is reported as the best scenario, since it can significantly increase the resilience of all sub-basins against extreme droughts with an acceptable cost of 636 million US dollars compared to other scenarios. Under this WERM scenario, the resilience values of sub-basins increase up to 40%. This scenario suggests implementing a set of projects such as improving irrigation networks and drainage facilities.

  • 19.
    Behboudian, Massoud
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering. School of Civil Engineering, College of Engineering, University of Tehran, Tehran, Iran.
    Kerachian, Reza
    School of Civil Engineering, College of Engineering, University of Tehran, Tehran, Iran.
    Motlaghzadeh, Kasra
    Department of System Design Engineering, University of Waterloo, Waterloo, Canada.
    Ashrafi, Saeed
    Department of Engineering System and Environment, University of Virginia, Charlottesville, VA, USA.
    Application of multi-agent decision-making methods in hydrological ecosystem services management2023In: MethodsX, ISSN 1258-780X, E-ISSN 2215-0161, Vol. 10, article id 102130Article in journal (Refereed)
    Abstract [en]

    In this paper, a methodology is presented for managing hydrological ecosystem services by taking into account the hierarchy of stakeholders involved in the decision-making process. With this in mind, a water allocation model is first used for allocating water resources to demands. Then, several ecosystem services (ESs)-based criteria are defined to evaluate hydrological ESs of water resources management policies. A set of water and environmental resources management strategies (alternatives) are defined for decision-makers, and several drought management strategies are determined to decrease the area of key crops and water demands of agricultural nodes. To model a multi-agent multi-criteria decision-making problem for managing hydrological ESs, three main steps are considered as follows: • Different ES-based criteria (i.e., economic profit, NPP,1 and ecological index) are defined, and their grade-based values are estimated. • Several strategies are defined for stakeholders at different levels. • A recursive evidential reasoning (ER) approach, which considers a hierarchical structure for decision-makers and a leader-follower game, is used to select the best strategy for each decision-maker.The applicability and efficiency of the methodology are illustrated by applying it to a real-world case study. The methodology is general and can be easily applied to other study areas.

  • 20. Bemmoussat, A.
    et al.
    Korichi, K.
    Baahmed, D.
    Maref, N.
    Djoukbala, O.
    Kalantari, Zahra
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. Department of Physical Geography, Stockholm University, Stockholm, Sweden..
    Bateni, S. M.
    Contribution of Satellite-Based Precipitation in Hydrological Rainfall–Runoff Modeling: Case Study of the Hammam Boughrara Region in Algeria2021In: Earth Systems and Environment, ISSN 2509-9426, Vol. 5, no 4, p. 873-881Article in journal (Refereed)
    Abstract [en]

    Hydrological models are viewed as powerful tools that have a major importance for managing water resources and predicting flows. It should be specified that the meteorological parameter rainfall is the main input in these models. In the current study, data from only one rainfall station are available over the analysis domain, which cannot represent the entire Hammam Boughrara watershed of Algeria. The precipitation data remotely detected by the tropical rainfall measuring mission (TRMM) provide good spatial coverage in the watershed and can be used to fill in the missing data. The use of raw TRMM data gives poor results from the simulated flow rates with a Nash–Sutcliffe efficiency NSE equal to 0.34 for the validation period that ranges from year 2000 to 2005; this is mainly due to uncertainties in the TRMM data. For this reason, it was deemed necessary to carry out a performance test of the model. The results obtained give an unsatisfactory percent bias (PBIAS) of − 46.24%, which suggests the need to perform a correction to decrease the PBIAS of satellite precipitation. For this, two methods were used: the linear regression method and the multiplicative method. These two techniques can only be applied if there is at least one rainfall measurement station available in the watershed. The obtained results are very satisfactory since the PBIAS reaches − 0.62% for the linear regression method and − 11.58% for the multiplicative method. In addition, the use of corrected TRMMs gives also very good results with a Nash–Sutcliffe efficiency that ranges from 0.74 to 0.88 for both validation and calibration periods. Overall, the current study is supportive to estimate the satellite-based rainfall, one of the very sensitive to measure the meteorological parameter, in northwestern Algeria.

  • 21. Berre, I.
    et al.
    Boon, Wietse M.
    KTH, School of Engineering Sciences (SCI), Mathematics (Dept.), Numerical Analysis, NA.
    Flemisch, B.
    Fumagalli, A.
    Gläser, D.
    Keilegavlen, E.
    Scotti, A.
    Stefansson, I.
    Tatomir, A.
    Brenner, K.
    Burbulla, S.
    Devloo, P.
    Duran, O.
    Favino, M.
    Hennicker, J.
    Lee, I. -H
    Lipnikov, K.
    Masson, R.
    Mosthaf, K.
    Nestola, M. G. C.
    Ni, C. -F
    Nikitin, K.
    Schädle, P.
    Svyatskiy, D.
    Yanbarisov, R.
    Zulian, P.
    Verification benchmarks for single-phase flow in three-dimensional fractured porous media2021In: Advances in Water Resources, ISSN 0309-1708, E-ISSN 1872-9657, Vol. 147, article id 103759Article in journal (Refereed)
    Abstract [en]

    Flow in fractured porous media occurs in the earth's subsurface, in biological tissues, and in man-made materials. Fractures have a dominating influence on flow processes, and the last decade has seen an extensive development of models and numerical methods that explicitly account for their presence. To support these developments, four benchmark cases for single-phase flow in three-dimensional fractured porous media are presented. The cases are specifically designed to test the methods’ capabilities in handling various complexities common to the geometrical structures of fracture networks. Based on an open call for participation, results obtained with 17 numerical methods were collected. This paper presents the underlying mathematical model, an overview of the features of the participating numerical methods, and their performance in solving the benchmark cases.

  • 22.
    Bhattacharya, Prosun
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Ahmed, K.M.
    Hasan, M.A.
    Broms, S.
    Fogelström, J.
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Sracek, O.
    von Brömssen, Mattias
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Routh, J.
    Mobility of arsenic in groundwater in a part of Brahmanbaria district, NE Bangladesh2006In: Managing Arsenic in the Environment: From soil to human health / [ed] Naidu, R., Smith, E., Owens, G., Bhattacharya, P. Nadebaum. P., Melbourne, Australia: CSIRO Publishing , 2006, p. 95-115Chapter in book (Refereed)
  • 23.
    Bhattacharya, Prosun
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Claesson, Mattias
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Fagerberg, Jens
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Bundschuh, Jochen
    Storniolo, Angel del R.
    Martin, Raul A.
    Thir, Juan Martin
    Sracek, Ondra
    Natural arsenic in the groundwater of the alluvial aquifers of Santiago del Estero Province, Argentina2005In: Natural Arsenic in Groundwater: Occurrence, Remediation and Management / [ed] Bundschuh, J; Bhattacharya, P; Chandrasekharam, D, London: Balkema, 2005, p. 57-65Conference paper (Refereed)
    Abstract [en]

    Natural occurrences of arsenic has been documented in groundwater of the shallow aquifers of the Chaco-Pampean Plain, Argentina. The distribution of arsenic and mechanisms of its mobilization in the shallow alluvial aquifers was investigated around the city of Santiago del Estero in Northwestern Argentina in order to provide an insight into the complex hydrological and geochemical conditions that yields high As concentrations in groundwater. Significant spatial variations of total arsenic (As-tot) concentrations were observed with an average value of 743 mu g/L. Arsenate was a dominant species in most samples. Average concentrations of Al, Mn, and Fe were 360 mu g/L, 574 mu g/L, and 459 mu g/L, respectively. The 7M HNO3 extraction of sediments and volcanic ash-layer indicated AS(N03) concentrations ranging between 2.5-7.1 mg/kg. AS(N03) indicated a significant positive correlation with Mn-N03, Al-N03, and Fe-N03. Oxalate extractions revealed significant fractions of As (Aso(ox)) in the sediments (0.4-1.4mg/kg) and a dominance of oxalate extractable Al- and Mn. Speciation calculations indicate that Al oxide and hydroxides have the potential to precipitate in the groundwater, suggesting that As adsorption processes may be to some extent controlled by Al oxides and hydroxides. Mobility of As at local scale seems to depend on high pH values, related to the dissolution of carbonates driven by cation exchange, and dissolution of silicates. There is a clear relationship of As with F, V, B and Si, suggesting their common origin in volcanic ash layer. Preliminary conceptual model of arsenic input includes release of As and Al from dissolution of volcanic ash layer, precipitation of Al oxides and hydroxides followed by adsorption of As on Al and Fe phases in sediments, and release of As under high pH conditions.

  • 24.
    Bhattacharya, Prosun
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Mukherjee, A.
    Mukherjee, A. B.
    Groundwater Arsenic in India: Source, Distribution, Effects and Alternate Safe Drinking Water Sources2013In: Reference Module in Earth Systems and Environmental Sciences, Elsevier, 2013Chapter in book (Other academic)
    Abstract [en]

    Elevated natural groundwater arsenic, a carcinogen, has created a severe environmental health crisis in several parts of India. Since the discovery of groundwater arsenic and arsenicosis in West Bengal, in 1984, a huge wealth of information has been generated by groundwater arsenic research during the last three decades. The principal mechanism of arsenic mobilization in groundwater is believed to be reductive dissolution of Fe-oxyhydroxides in aquifer sediments. Arsenic enriched groundwater used for irrigation also leads to long-term risks for arsenic enrichment in the soils and bioaccumulation in crops. Various studies are ongoing to develop a holistic approach for arsenic mitigation.

  • 25.
    Bhattacharya, Prosun
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    von Brömssen, M.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Hasan, M.A.
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Ahmed, K.M.
    Sracek, O.
    Jakariya, M.
    Huq, S.M.I.
    Naidu, R.
    Smith, E.
    Owens, G.
    Arsenic mobilisation in the Holocene flood plains in South-central Bangladesh: Evidences from the hydrogeochemical trends and modeling results2008In: Groundwater for Sustainable Development: Problems, Perspectives and Challenges / [ed] Bhattacharya, P., Ramanathan, AL., Mukherjee A.B., Bundschuh, J., Chandrasekharam, D. Keshari, A.K., The Netherlands: Taylor and Francis/A.A. Balkema , 2008, p. 283-299Chapter in book (Refereed)
  • 26.
    Bishop, Adrian N.
    et al.
    KTH, School of Computer Science and Communication (CSC), Computer Vision and Active Perception, CVAP.
    Fidan, Baris
    Anderson, Brian D. O.
    Dogancay, Kutluyil
    Pathirana, Pubudu N.
    Optimal Range-Difference-Based Localization Considering Geometrical Constraints2008In: IEEE Journal of Oceanic Engineering, ISSN 0364-9059, E-ISSN 1558-1691, Vol. 33, no 3, p. 289-301Article in journal (Refereed)
    Abstract [en]

    This paper proposes a new type of algorithm aimed at finding the traditional maximum-likelihood (TML) estimate of the position of a target given time-difference-of-arrival (TDOA) information, contaminated by noise. The novelty lies in the fact that a performance index, akin to but not identical with that in maximum likelihood (ML), is a minimized subject to a number of constraints, which flow from geometric constraints inherent in the underlying problem. The minimization is in a higher dimensional space than for TML, and has the advantage that the algorithm can be very straightforwardly and systematically initialized. Simulation evidence shows that failure to converge to a solution of the localization problem near the true value is less likely to occur with this new algorithm than with TML. This makes it attractive to use in adverse geometric situations.

  • 27.
    Blomgren, Axel
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Stockholms grundvattenkvalitet: Bidrag till övergödningen av ytvattendrag och sjöar i Stockholmsområdet2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Eutrophication is one of Sweden’s most severe environmental issues. Due to emissions through anthropogenic activity nutrients are added to aquatic systems. The latest analysis of the Stockholm municipality groundwater has examined the levels of nitrogen and phosphorus. Due to the fact that the groundwater is part of the hydrological cycle and will eventually reach the surface water, the condition of the groundwater will affect the recipient and correlating ecosystem. This report aims to analyze the levels of nitrogen and phosphorus in the groundwater of Stockholm based on current national quality standards, and to identify whether the groundwater is contributing to the eutrophication of the surface water bodies in the municipality of Stockholm. This is of significance regarding the water management in Stockholm municipality, based on the EU water framework directive, and the target of achieving good status for all water bodies. It is also of great importance regarding the Swedish environmental quality objectives.

    The groundwater quality analysis indicates high levels of phosphorus and ammonium. The nitrate and nitrite levels are only excessive in certain cases. Primarily, the levels of phosphorus and ammonium may, according to national quality standards, have eutrophic effect on surface water bodies. A cursory examination based on the flow directions of the groundwater, indicates that the municipality’s surface waters are supplied with water from the municipality’s groundwater. This correlation is represented in the analysis of groundwater quality and it is therefore concluded that the groundwater has a negative impact on the surface water bodies within the municipality. 

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  • 28.
    Bostrom, Mathias
    et al.
    Univ Oslo, Dept Phys, Ctr Mat Sci & Nanotechnol, POB 1048, N-0316 Oslo, Norway..
    Esteso, Victoria
    Univ Seville, Multifunct Opt Mat Grp, Inst Ciencia Mat Sevilla, CSIC, Calle Americo Vespucio 49, Seville 41092, Spain..
    Fiedler, Johannes
    Albert Ludwigs Univ Freiburg, Phys Inst, Hermann Herder Str 3, D-79104 Freiburg, Germany.;Univ Bergen, Dept Phys & Technol, Allegaten 55, N-5007 Bergen, Norway..
    Brevik, Iver
    Norwegian Univ Sci & Technol, Dept Energy & Proc Engn, N-7491 Trondheim, Norway..
    Buhmann, Stefan Yoshi
    Univ Kassel, Inst Phys, Heinrich Plett Str 40, D-34132 Kassel, Germany..
    Persson, Clas
    Univ Oslo, Dept Phys, Ctr Mat Sci & Nanotechnol, POB 1048, N-0316 Oslo, Norway..
    Carretero-Palacios, Sol
    Univ Autonoma Madrid, Dept Fis Mat, Madrid 28049, Spain..
    Parsons, Drew F.
    Univ Cagliari, Dept Chem & Geol Sci, I-09042 Monserrato, CA, Italy.;Murdoch Univ, Discipline Chem & Phys, CSHEE, 90 South St, Murdoch, WA 6150, Australia..
    Corkery, Robert
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science. Australian Natl Univ, Res Sch Phys, Dept Appl Math, ANU Coll Sci, Oliphant Bldg 60,Mills Rd, Canberra, ACT 2601, Australia..
    Self-preserving ice layers on CO2 clathrate particles: Implications for Enceladus, Pluto, and similar ocean worlds2021In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 650, article id A54Article in journal (Refereed)
    Abstract [en]

    Context. Gas hydrates can be stabilised outside their window of thermodynamic stability by the formation of an ice layer - a phenomenon termed self-preservation. This can lead to a positive buoyancy for clathrate particles containing CO2 that would otherwise sink in the oceans of Enceladus, Pluto, and similar oceanic worlds.Aims. Here we investigate the implications of Lifshitz forces and low occupancy surface regions on type I clathrate structures for their self-preservation through ice layer formation, presenting a plausible model based on multi-layer interactions through dispersion forces.Methods. We used optical data and theoretical models for the dielectric response for water, ice, and gas hydrates with a different occupancy. Taking this together with the thermodynamic Lifshitz free energy, we modelled the energy minima essential for the formation of ice layers at the interface between gas hydrate and liquid water.Results. We predict the growth of an ice layer between 0.01 and 0.2 mu m thick on CO, CH4, and CO2 hydrate surfaces, depending on the presence of surface regions depleted in gas molecules. Effective hydrate particle density is estimated, delimiting a range of particle size and compositions that would be buoyant in different oceans. Over geological time, the deposition of floating hydrate particles could result in the accumulation of kilometre-thick gas hydrate layers above liquid water reservoirs and below the water ice crusts of their respective ocean worlds. On Enceladus, the destabilisation of near-surface hydrate deposits could lead to increased gas pressures that both drive plumes and entrain stabilised hydrate particles. Furthermore, on ocean worlds, such as Enceladus and particularly Pluto, the accumulation of thick CO2 or mixed gas hydrate deposits could insulate its ocean against freezing. In preventing freezing of liquid water reservoirs in ocean worlds, the presence of CO2-containing hydrate layers could enhance the habitability of ocean worlds in our Solar System and on the exoplanets and exomoons beyond.

  • 29.
    Boulet, Anne-Karine
    et al.
    CERNAS, Coimbra Agr Tech Sch, PC-304560 Coimbra, Portugal.;Univ Aveiro, CESAM Environm & Planning Dept, Campus Univ Santiago, PC-381019 Aveiro, Portugal..
    Rial-Rivas, Mitas E.
    Univ Aveiro, CESAM Environm & Planning Dept, Campus Univ Santiago, PC-381019 Aveiro, Portugal..
    Ferreira, Carla
    CERNAS, Coimbra Agr Tech Sch, PC-304560 Coimbra, Portugal.;Stockholm Univ, Dept Phys Geog, SE-10691 Stockholm, Sweden.;Bolin Ctr Climate Res, SE-10691 Stockholm, Sweden.;Navarino Environm Observ, Messinia 24001, Greece..
    Coelho, Celeste O. A.
    Univ Aveiro, CESAM Environm & Planning Dept, Campus Univ Santiago, PC-381019 Aveiro, Portugal..
    Kalantari, Zahra
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering. Stockholm Univ, Dept Phys Geog, SE-10691 Stockholm, Sweden.;Bolin Ctr Climate Res, SE-10691 Stockholm, Sweden.;Navarino Environm Observ, Messinia 24001, Greece.;KTH Royal Inst Technol, Dept Sustainable Dev Environm Sci & Engn SEED, SE-10044 Stockholm, Sweden..
    Keizer, Jan Jacob
    Univ Aveiro, CESAM Environm & Planning Dept, Campus Univ Santiago, PC-381019 Aveiro, Portugal..
    Ferreira, Antonio J. D.
    CERNAS, Coimbra Agr Tech Sch, PC-304560 Coimbra, Portugal..
    Hydrological Processes in Eucalypt and Pine Forested Headwater Catchments within Mediterranean Region2021In: Water, E-ISSN 2073-4441, Vol. 13, no 10, article id 1418Article in journal (Refereed)
    Abstract [en]

    Mediterranean headwater catchments have experienced major land-use changes in recent centuries, namely characterized by afforestation with fast-growing tree species (e.g., pine and eucalyptus). This paper investigates differences in the hydrological response of two forested catchments with distinct Pinus pinaster Aiton (PIN) and Eucalyptus globulus Labill. (EUC) covers over 6 hydrological years, from 2010 to 2016. The study was developed in paired catchments located in North-Central Portugal, under wet Mediterranean climate and schist bedrock. Based on rainfall and streamflow measurements, the hydrological responses were analyzed through the water-balance calculations, rainfall-runoff event analyses, and correlations between rainfall characteristics, evapotranspiration, soil moisture, overland flow, and land-cover parameters. The study period recorded a wide range of annual rainfall, between 984 and 2127 mm per years. The annual streamflow displayed greater inter-annual variation, from 208 to 1430 mm for PIN and from 217 to 1291 mm for EUC. The runoff coefficient was higher in the wettest years, with a maximum of 58% for PIN and 61% for EUC, and decreased substantially in the driest year, representing only 17% of the rainfall in PIN and 22% in EUC. Rainfall was predominant during the winter season (41%), followed by autumn (30%) and spring (24%). The streamflow displayed a seasonal behavior in both catchments, with higher runoff coefficient for EUC that for PIN. Half of the annual streamflow occurs during the winter, with the highest average runoff coefficient attained for EUC and PIN respectively being 68% and 64% of the rainfall amount. Annual evapotranspiration was relatively constant through the six years of study and showed higher average values in PIN (907 mm) than EUC (739 mm), highlighting the importance of forest type and showing that mature pine plantations lead to higher water consumption than eucalypt stands. Annual rainfall amount affects evapotranspiration rate (%), the percentage of ET increasing from 37% to 78% for PIN and from 34% to 73% for EUC between the wettest and the driest years, which raises concerns regarding the impact of climate changes on water availability in the mountain areas of the Mediterranean region.

  • 30. Bulbul, A.
    et al.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Huq, S.M.I.
    Gunaratna, K.R.
    Arsenic uptake by fresh water green alga, Chlamydomonas2008In: Groundwater for Sustainable Development: Problems, Perspectives and Challenges / [ed] Bhattacharya, P., Ramanathan, AL., Mukherjee A.B., Bundschuh, J., Chandrasekharam, D. Keshari, A.K., The Netherlands: Taylor and Francis/A. A. Balkema , 2008, p. 389-396Chapter in book (Refereed)
  • 31.
    Bundschuh, Jochen
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Bhattacharya, ProsunKTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.Chandrashekharam, D.
    Natural Arsenic in Groundwater: Occurrence, Remediation and Management2005Collection (editor) (Refereed)
  • 32.
    Bundschuh, Jochen
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    von Brömssen, Mattias
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Jakariya, Md
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Litter, M.I.
    Garcia, M.E.
    Arsenic-safe aquifers as a socially acceptable source of safe drinking water: What can rural Latin America learn from Bangladesh experiences?2009In: Natural Arsenic in Groundwater of Latin America: Occurrence, health impact and remediation, The Netherlands: CRC Press/Balkema , 2009, p. 677-685Chapter in book (Refereed)
  • 33. Bäckstrom, M.
    et al.
    Karlsson, S.
    Bäckman, L.
    Folkeson, Lennart
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Lind, B.
    Mobilisation of heavy metals by deicing salts in a roadside environment2004In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 38, no 3, p. 720-732Article in journal (Refereed)
    Abstract [en]

    The seasonal variations of some selected heavy metals (Cd, Cu, Pb and Zn) and principal anions in soil solutions were monitored as a function of distance from the road at two field sites in Sweden. During the winter, the conductivity, concentrations of dissolved sodium and chloride increased dramatically due to the application of deicing agents (i.e. NaCl). Due to ion exchange, the pH decreased one unit in the soil solutions, whereas the concentrations of total organic carbon decreased due to coagulation and/or sorption to stationary solids. The heavy metal concentrations increased during the winter, but through different mechanisms. Cadmium concentrations in the aqueous phase increased as a response to ion exchange, possibly also enhanced by the formation of chloride complexes. Similarly, the concentrations of zinc increased, due to ion exchange, with calcium and protons. The mechanisms of mobilisation for copper and lead were not that clear probably due to association with coagulated or sorbed organic matter in combination with colloid dispersion.

  • 34.
    Campagne, Antoine
    et al.
    LEGI, Université Grenoble Alpes.
    Alfredsson, Henrik
    KTH, School of Engineering Sciences (SCI), Centres, Linné Flow Center, FLOW. KTH, School of Engineering Sciences (SCI), Mechanics.
    Chassagne, Rémi
    LEGI, Université Grenoble Alpes.
    Micard, Diane
    LMFA, École Centrale de Lyon.
    Mordant, Nicolas
    LEGI, Université Grenoble Alpes.
    Segalini, Antonio
    KTH, School of Engineering Sciences (SCI), Centres, Linné Flow Center, FLOW. KTH, School of Engineering Sciences (SCI), Mechanics.
    Sommeria, Joel
    LEGI, Université Grenoble Alpes.
    Viboud, Samuel
    LEGI, Université Grenoble Alpes.
    Mohanan, Ashwin Vishnu
    KTH, School of Engineering Sciences (SCI), Centres, Linné Flow Center, FLOW. KTH, School of Engineering Sciences (SCI), Mechanics.
    Lindborg, Erik
    KTH, School of Engineering Sciences (SCI), Centres, Linné Flow Center, FLOW. KTH, School of Engineering Sciences (SCI), Mechanics.
    Augier, Pierre
    LEGI, Université Grenoble Alpes.
    First report of the MILESTONE experiment: strongly stratified turbulence and mixing efficiency in the Coriolis platform2016In: VIIIth International Symposium on Stratified Flows (ISSF), 2016, 2016Conference paper (Refereed)
    Abstract [en]

    Strongly stratified turbulence is a possible interpretation of oceanic and atmospheric mea-surements. However, this regime has never been produced in a laboratory experiment be-cause of the two conditions of very small horizontal Froude number Fh and large buoyancy Reynolds number R which require a verily large experimental facility. We present a new attempt to study strongly stratified turbulence experimentally in the Coriolis platform.The flow is forced by a slow periodic movement of an array of six vertical cylinders of 25 cm diameter with a mesh of 75 cm. Five cameras are used for 3D-2C scanned horizontalparticles image velocimetry (PIV) and stereo 2D vertical PIV. Five density-temperatureprobes are used to measure vertical and horizontal profiles and signals at fixed positions.The first preliminary results indicate that we manage to produce strongly stratified tur-bulence at very small Fh and large R in a laboratory experiment.

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  • 35.
    Campana, Pietro Elia
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Zhang, J.
    Univ Maryland, Dept Geog Sci, College Pk, MD 20742 USA..
    Yao, T.
    Sci Syst & Applicat Inc SSAI, Lanham, MD 20706 USA.;NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA..
    Andersson, S.
    Swedish Meteorol & Hydrol Inst, SE-60176 Norrkoping, Sweden..
    Landelius, T.
    Swedish Meteorol & Hydrol Inst, SE-60176 Norrkoping, Sweden..
    Melton, F.
    NASA ARC CREST, Moffett Field, CA 94035 USA.;Calif State Univ Monterey Bay, Sch Nat Sci, Seaside, CA 93955 USA..
    Yan, Jerry
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Malardalen Univ, Future Energy Ctr, Sch Business Soc & Engn, SE-72123 Vasteras, Sweden.;KTH Royal Inst Technol, Dept Chem Engn, SE-10044 Stockholm, Sweden..
    Managing agricultural drought in Sweden using a novel spatially-explicit model from the perspective of water-food-energy nexus2018In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 197, p. 1382-1393Article in journal (Refereed)
    Abstract [en]

    Using a multi-disciplinary approach, this paper integrated spatial analysis with agricultural and energy system modelling to assess the impacts of drought on crop water demand, water availability, crop yield, and electricity requirements for irrigation. This was done by a novel spatially-explicit and integrated water-food-energy nexus model, using the spatial climatic data generated by the mesoscale MESAN and STRANG models. In this study, the model was applied to quantify the effects of drought on the Swedish irrigation sector in 2013, a typical drought year, for a specific crop. The results show that drought can severely affect the crop yield if irrigation is not applied, with a peak yield reduction of 18 t/ha, about 50 % loss as compared to the potential yield in irrigated conditions. Accordingly, the water and energy requirements for irrigation to halt the negative drought effects and maintain high yields are significant, with the peaks up to 350 mm and 700 kWh per hectare. The developed model can be used to provide near real-time guidelines for a comprehensive drought management system. The model also has significant potentials for applications in precision agriculture, especially using high-resolution satellite data.

  • 36.
    Cantoni, Jacopo
    et al.
    Stockholm Univ, Dept Phys Geog, SE-10691 Stockholm, Sweden..
    Kalantari, Zahra
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. Stockholm Univ, Dept Phys Geog, SE-10691 Stockholm, Sweden..
    Destouni, Georgia
    Stockholm Univ, Dept Phys Geog, SE-10691 Stockholm, Sweden..
    Legacy contributions to diffuse water pollution: Data-driven multi-catchment quantification for nutrients and carbon2023In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 879, p. 163092-, article id 163092Article in journal (Refereed)
    Abstract [en]

    Legacy pollutants are increasingly proposed as possible reasons for widespread failures to improve water quality, de -spite the implementation of stricter regulations and mitigation measures. This study investigates this possibility, using multi-catchment data and relatively simple, yet mechanistically-based, source distinction relationships between water discharges and chemical concentrations and loads. The relationships are tested and supported by the available catch -ment data. They show dominant legacy contributions for total nitrogen (TN), total phosphorus (TP) and total organic carbon (TOC) across catchment locations and scales, from local to country-wide around Sweden. Consistently across the study catchments, close relationships are found between the legacy concentrations of TN and TOC and the land shares of agriculture and of the sum of agriculture and forests, respectively. The legacy distinction and quantification capabilities provided by the data-driven approach of this study could guide more effective pollution mitigation and should be tested in further research for other chemicals and various sites around the world.

  • 37.
    Carstens, Christoffer
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Water Resources Engineering.
    In the Pipe or End of Pipe?: Transport and Dispersion of Water-borne Pollutants and Feasibility of Abatement Measures2012Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Eutrophication is one of the key environmental problems of today, both in terms of complexity and magnitude. For the Baltic Sea (BS), eutrophication is an acute problem, leading to hypoxic conditions at the bottom; a situation that is sustained and amplified, when phosphorus is released from hypoxic sediments. Reducing nutrient loading is a top political priority but the present situation is believed to require active measures within the catchments and recipients to reduce both loading and adverse effects. Implementation of effective and cost-efficient abatement methods requires understanding of natural processes in watersheds, streams and recipients as well as technological expertise in order to compare the effects of measures of different kinds and locations. This thesis tries to combine process understanding of catchment transport behaviour, especially in coastal zones, and feasibility of certain technologies for reducing nutrient loading and effects of eutrophication in-situ. The over-arching theme is the fate of the individual contaminant, from injection to removal. Transport and dispersion in catchments are investigated, combining physically-based, distributed, numerical groundwater models with Lagrangian stochastic advective reactive solute (LaSAR) transport modelling. The approach is powerful in the sense that it incorporates catchment structural, geomorphological dispersion in the numerical model with hydrodynamic and sub-scale dispersion as well as uncertainty in the LaSAR framework. The study exemplifies the complex nature of transport time distributions in catchments in general and when varying source size and location, importance of dispersion parameters and retention due to molecular diffusion. It is shown that geomorphological control on dispersion is present even for relatively heterogeneous systems and that neither the mean residence time nor a statistical distribution may provide accurate representations of hydrological systems. To combat internal loading of P from sediments in-situ, large-scale aeration of deep waters, halocline ventilation, has been suggested. This study further investigates the feasibility of wave-powered devices to meet the energy demands for such an operation. It is shown that the required amount of oxygen needed to keep the sediments at oxic conditions could be provided, cheaply and efficiently, through the use of wave power.

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  • 38. Cascone, C.
    et al.
    Murphy, K. R.
    Markensten, H.
    Kern, J. S.
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics.
    Schleich, C.
    Keucken, A.
    Köhler, S. J.
    AbspectroscoPY, a Python toolbox for absorbance-based sensor data in water quality monitoring2022In: Environmental Science: Water Research & Technology, ISSN 2053-1400, E-ISSN 2053-1419, Vol. 8, no 4, p. 836-848Article in journal (Refereed)
    Abstract [en]

    The long-term trend of increasing natural organic matter (NOM) in boreal and north European surface waters represents an economic and environmental challenge for drinking water treatment plants (DWTPs). High-frequency measurements from absorbance-based online spectrophotometers are often used in modern DWTPs to measure the chromophoric fraction of dissolved organic matter (CDOM) over time. These data contain valuable information that can be used to optimise NOM removal at various stages of treatment and/or diagnose the causes of underperformance at the DWTP. However, automated monitoring systems generate large datasets that need careful preprocessing, followed by variable selection and signal processing before interpretation. In this work we introduce AbspectroscoPY (“Absorbance spectroscopic analysis in Python”), a Python toolbox for processing time-series datasets collected by in situ spectrophotometers. The toolbox addresses some of the main challenges in data preprocessing by handling duplicates, systematic time shifts, baseline corrections and outliers. It contains automated functions to compute a range of spectral metrics for the time-series data, including absorbance ratios, exponential fits, slope ratios and spectral slope curves. To demonstrate its utility, AbspectroscoPY was applied to 15-month datasets from three online spectrophotometers in a drinking water treatment plant. Despite only small variations in surface water quality over the time period, variability in the spectrophotometric profiles of treated water could be identified, quantified and related to lake turnover or operational changes in the DWTP. This toolbox represents a step toward automated early warning systems for detecting and responding to potential threats to treatment performance caused by rapid changes in incoming water quality. 

  • 39.
    Cheemakurthy, Harsha
    et al.
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering.
    Zhang, Meng
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering.
    Garme, Karl
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Naval Systems.
    Burman, Magnus
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Lightweight Structures.
    Ehlers, S.
    Germany.
    Franz Von Bock, R. U.
    Germany.
    Polach, x
    Germany.
    Statistical estimation of uncertainties associated with ship operations in fresh water ice2018In: Proceedings of the International Offshore and Polar Engineering Conference, International Society of Offshore and Polar Engineers , 2018, p. 1608-1615Conference paper (Refereed)
    Abstract [en]

    Operational Time Window (OTW) and its confidence level are important for vessels operating in ice covered waters. This can be evaluated by quantifying all contributing factors in terms of their influence along with respective associated uncertainties. For a case study involving a barge operating in Lake Mälaren, Sweden, five criteria are evaluated, and associated uncertainties are quantified using Variation Mode and Effect Analysis (VMEA) to give individual contribution towards overall uncertainty. Ship resistance due to ice and ice loads dominated over other criteria with highest contributions to uncertainty at 28% and 72% respectively.

  • 40.
    Chen, Yuanying
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Land-Sea Interactions in the Coastal-Marine System of the Baltic Sea under Hydro-Climatic Variability2020Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

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

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

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

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  • 41.
    Chen, Yuanying
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. Stockholm Univ, Dept Phys Geog, S-10691 Stockholm, Sweden..
    Cvetkovic, Vladimir
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Destouni, Georgia
    Stockholm Univ, Dept Phys Geog, S-10691 Stockholm, Sweden..
    Scenarios of Nutrient-Related Solute Loading and Transport Fate from Different Land Catchments and Coasts into the Baltic Sea2019In: Water, E-ISSN 2073-4441, Vol. 11, no 7, article id 1407Article in journal (Refereed)
    Abstract [en]

    This study uses controlled numerical experimentation to comparatively simulate and investigate solute transport and concentration responses and patterns in the Baltic Sea for various solute releases from the land through two different coastal cases. These cases are the Swedish Kalmar County coast and the Polish coast of the Vistula River outlet. For equivalent solute releases, the coastal flow conditions and their interactions with main marine currents determine the local coastal solute spreading, while the overall spreading over the Baltic Sea is similar for the two coastal cases, despite their large local differences. For nutrient-proportional solute release scenarios, the highly-populated Vistula catchment yields much greater total, but smaller per-capita nutrient impacts, in the Baltic Sea than the Kalmar County catchment. To be as low as from the Vistula catchment, the per-capita nutrient contribution from Kalmar County would have to be reduced much more than required on average per Swedish inhabitant by the Baltic Sea Action Plan. This highlights an unfairness issue in the per-capita distribution of nutrient load allowance among the Baltic countries, which needs to be considered and handled in further research and international efforts aimed to combat the Baltic Sea eutrophication.

  • 42.
    Chen, Yuanying
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. Stockholm Univ, Dept Phys Geog, Stockholm, Sweden..
    Destouni, Georgia
    Stockholm Univ, Dept Phys Geog, Stockholm, Sweden..
    Goldenberg, Romain
    Stockholm Univ, Dept Phys Geog, Stockholm, Sweden..
    Prieto, Carmen
    Stockholm Univ, Dept Phys Geog, Stockholm, Sweden..
    Nutrient source attribution: Quantitative typology distinction of active and legacy source contributions to waterborne loads2021In: Hydrological Processes, ISSN 0885-6087, E-ISSN 1099-1085, Vol. 35, no 7, article id e14284Article in journal (Refereed)
    Abstract [en]

    Distinction between active and legacy sources of nutrients is needed for effective reduction of waterborne nutrient loads and associated eutrophication. This study quantifies main typological differences in nutrient load behaviour versus water discharge for active and legacy sources. This quantitative typology is used for source attribution based on monitoring data for water discharge and concentrations of total nitrogen (TN) and total phosphorous (TP) from 37 catchments draining into the Baltic Sea along the coastline of Sweden over the period 2003-2013. Results indicate dominant legacy source contributions to the monitored loads of TN and TP in most (33 of the total 37) study catchments. Dominant active sources are indicated in 1 catchment for TN, and mixed sources are indicated in 3 catchments for TN, and 4 catchments for TP. The TN and TP concentration contributions are quantified to be overall higher from the legacy than the active sources. Legacy concentrations also correlate well with key indicators of human activity in the catchments, agricultural land share for TN (R-2 = 0.65) and population density for TP (R-2 = 0.56). Legacy-dominated nutrient concentrations also change more slowly than in catchments with dominant active or mixed sources. Various data-based results and indications converge in indicating legacy source contributions as largely dominant, mainly anthropogenic, and with near-zero average change trends in the present study of catchments draining into the Baltic Sea along the coastline of Sweden, as in other parts of the world. These convergent indications emphasize needs to identify and map the different types of sources in each catchment, and differentiate strategies and measures to target each source type for possible achievement of shorter- and longer-term goals of water quality improvement.

  • 43.
    Chen, Yuanying
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. Department of Physical Geography, Stockholm University.
    Prieto, Carmen
    Department of Physical Geography, Stockholm University.
    Goldenberg, Romain
    Department of Physical Geography, Stockholm University.
    Destouni, Georgia
    Department of Physical Geography, Stockholm University.
    Distinguishing nutrient contributions from legacy and active sources along the Swedish coastManuscript (preprint) (Other academic)
  • 44.
    Coello-Balthasar, Zairis
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Phumpiu, Patricia
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Water Management.
    Balfors, Berit
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Gustafsson, Jan-Erik
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Water Management.
    Assessment of causes leading to an insufficient water supply in Tegucigalpa, Honduras2011In: WIT Transactions on Ecology and the Environment, ISSN 1743-3541, Vol. 145, p. 27-38Article in journal (Refereed)
  • 45.
    Cucarella Cabañas, Victor
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Phosphorus recycling from wastewater to agriculture using reactive filter media2007Licentiate thesis, comprehensive summary (Other scientific)
    Abstract [en]

    This thesis focused on testing the suitability of reactive filter media used for phosphorus (P) removal from wastewater as fertilizers, thus recycling P to agriculture. The work compared the P sorption capacity of several materials in order to assess their suitability as a source of P for plants. The selected materials (Filtra P, Polonite and wollastonite) were saturated with P and used as soil amendments in a pot experiment. The amendments tended to improve the yield of barley and ryegrass compared with no P addition. The amendments also increased soil pH, P availability and cation exchange capacity in the studied soils. The substrates studied here can be of particular interest for acid soils. Of the materials studied, Polonite appears to be the most suitable substrate for the recycling of P from wastewater to agriculture

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  • 46.
    Cucarella, Victor
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Zaleski, Tomasz
    Department of Soil Science and Soil Protection, Agricultural University of Cracow, Poland.
    Mazurek, Ryszard
    Department of Soil Science and Soil Protection, Agricultural University of Cracow, Poland.
    Phosphorus sorption capacity of different types of opoka2007In: Annals of Warsaw University of Life Sciences – SGGW Land Reclamation, ISSN 1898-8857, Vol. 38, p. 11-18Article in journal (Refereed)
    Abstract [en]

    Phosphorus sorption capacity ofdifferent types of opoka. The bedrock opoka hasbeen lately reported as an appropriate reactivemedia for onsite wastewater treatment systemsdue to its high phosphorus (P) sorption capacity.However, variations on its chemical compositionmay affect its reactivity with P, therefore leadingto a variable P removal effi ciency. In this paper,the P-sorption capacity of three different typesof opoka from the region of Miechów, Poland,is reported. According to the silica and carbonatecontent, opoka samples were classifi ed as light--weight and heavy-weight opoka. When heatedover 900°C, opoka showed a very high P-sorptioncapacity that was well correlated to its Ca content.P-sorption isotherms from batch experiments withan artifi cial P solution were plotted and fi tted tothe Langmuir and Freundlich adsorption models.The Freundlich isotherm appeared to model betterthe P-sorption of light opoka and the Langmuirisotherm of heavy opoka, suggesting differentdominating mechanisms of P-sorption by lightand heavy opoka.

  • 47.
    Cucarella, Victor
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Zaleski, Tomasz
    Department of Soil Science and Soil Protection, Agricultural University of Cracow.
    Mazurek, Ryszard
    Department of Soil Science and Soil Protection, Agricultural University of Cracow.
    Renman, Gunno
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Effect of reactive substrates used for phosphorus removal from wastewater on the feritlity of acid soils2008In: Bioresource Technology, ISSN 0960-8524, E-ISSN 1873-2976, Vol. 99, no 10, p. 4308-4314Article in journal (Refereed)
    Abstract [en]

    Reactive substrates used in filter systems can reduce phosphorus (P) pollution and, once saturated with P, may be recycled in agriculture. These substrates are usually calcium carbonate derivates with high pH values, which may be particularly beneficial for acid soils. Three reactive substrates (Filtra P, Polonite and wollastonite) saturated with P were used as amendments to an acid soil in a pot experiment. Substrate amendments tended to improve ryegrass yield and P uptake compared with control and potassium phosphate treatments. Polonite produced the highest yield/amendment ratio, while Polonite and Filtra P significantly increased the concentrations of P and Ca in the ryegrass. Addition of all three substrates increased the pH, AL-extractable P and cation exchange capacity of soils during the experiment. These substrates can therefore be applied to acid soils in order to recycle P and improve soil properties.

  • 48.
    Cvetkovic, Vladimir
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Water Resources Engineering.
    Carstens, Christoffer
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Water Resources Engineering.
    Selroos, Jan-Olof
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. Department of Geoscience and Safety, Swedish Nuclear Fuel and Waste Management Co., Stockholm, Sweden.
    Destouni, Georgia
    Water and solute transport along hydrological pathways2012In: Water resources research, ISSN 0043-1397, E-ISSN 1944-7973, Vol. 48, no 6, p. W06537-Article in journal (Refereed)
    Abstract [en]

    A Lagrangian framework for material transport along hydrological pathways is presented and consequences of statistically stationary space-time flow velocity variations on advective transport are investigated. The two specific questions addressed in this work are: How do temporal fluctuations affect forward and backward water travel time distributions when combined with spatial variability? and Can mass transfer processes be quantified using conditional probabilities in spatially and temporally variable flow? Space-time trajectories are studied for generic conditions of flow, with fully ergodic or only spatially ergodic velocity. It is shown that forward and backward distributions of advective water travel time coincide for statistically stationary space-time variations. Temporal variability alters the statistical structure of the Lagrangian velocity fluctuations. Once this is accounted for, integration of the memory function with the travel time distribution is applicable for quantifying retention. Further work is needed to better understand the statistical structure of space-time velocity variability in hydrological transport, as well as its impact on tracer retention and attenuation.

  • 49.
    Cvetkovic, Vladimir
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Fiori, A.
    Dagan, G.
    Tracer travel and residence time distributions in highly heterogeneous aquifers: Coupled effect of flow variability and mass transfer2016In: Journal of Hydrology, ISSN 0022-1694, E-ISSN 1879-2707Article in journal (Refereed)
    Abstract [en]

    The driving mechanism of tracer transport in aquifers is groundwater flow which is controlled by the heterogeneity of hydraulic properties. We show how hydrodynamics and mass transfer are coupled in a general analytical manner to derive a physically-based (or process-based) residence time distribution for a given integral scale of the hydraulic conductivity; the result can be applied for a broad class of linear mass transfer processes. The derived tracer residence time distribution is a transfer function with parameters to be inferred from combined field and laboratory measurements. It is scalable relative to the correlation length and applicable for an arbitrary statistical distribution of the hydraulic conductivity. Based on the derived residence time distribution, the coefficient of variation and skewness of residence time are illustrated assuming a log-normal hydraulic conductivity field and first-order mass transfer. We show that for a low Damkohler number the coefficient of variation is more strongly influenced by mass transfer than by heterogeneity, whereas skewness is more strongly influenced by heterogeneity.

  • 50. Dagan, G.
    et al.
    Fiori, A.
    Jankovic, I.
    Cvetkovic, Vladimir
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Tailing of the breakthrough curve in aquifer contaminant transport: The impact of permeability spatial variability2008Conference paper (Refereed)
    Abstract [en]

    A contaminant plume of mass Mo is inserted at time t = 0 at an injection plane at × = 0 in an aquifer of spatially variable conductivity K. The log-conductivity Y = InK is modelled as stationary and isotropic, of univariate distribution f(Y), and of finite integral scale I. The flow of water is uniform in the mean (natural gradient) and the plume is of large transverse extent relative to the integral scale. Advective transport and longitudinal spread are quantified by the solute mass arrival ("breakthrough curve", BTC) M(t,x) at a control plane at × &gt; I. For a large plume (ergodic conditions) the relative mass flux μ(t,x) = (l/Mo)M/t is approximately equal to the probability density function of travel times of solute particles f(τx) and the latter is used to analyse transport. f(τx) is derived by adopting a structural model of the aquifer that contains spherical or cubic inclusions of uniform size and of independent Y that fill the space. Such a structure can represent any formation of given f(Y) and I. The flow and transport solutions are obtained by a simple semianalytical model and by accurate numerical simulations. The travel time distribution at few control planes is determined for a log-normal f(K) first. Under the assumption of weak heterogeneity, i.e. for small variance σy 2 and for x»I, the travel time distribution is symmetrical and Gaussian. Subsequently, by using the semi-analytical model and numerical simulations we derive f(τx) for a highly heterogeneous formation of σ y 2 = 2. The main finding is f(τx) is highly skewed due to the presence of a thin, but long tail, for large travel times. The tail is of significance to applications that deal with aquifer pollution and remediation. The tail is related to the large residence time of solute particles in blocks of low conductivity. A simple relationship is established between the tail of f(Y) for low K and that f(τx) for large τ. To further examine the impact of the log-conductivity distribution on BTC tailing, a non-Gaussian model, the subordinate model, is adopted for f(Y). This distribution depends on an additional parameter Is; travel time distribution tends to normal for Is→0, whereas the tails of the two distributions are different for Is &gt; 0. This choice reflects the difficulty of identification of the tail of f(Y) based on field data. The relevance of results to applications is examined in terms of impact of conductivity spatial distribution, as well as influence of plume size (non-ergodic behaviour) and diffusion.

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