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  • 151.
    Hector, Hélène
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Obstructions monitoring in sewerage pipes.2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    When a malfunction in the collection system occurs and a pipe overflows, the wastewater may be discharged in the natural environment. To avoid such pollution, nuisances to inhabitants living nearby and extra cost for the operator, there is an issue of detecting early enough the buildup of obstructions in sewerage pipes in order to react before the damage is done.

    The aim of this thesis was thus to develop a decision support tool to detect obstructions and to optimize cleaning operations. Some additional specifications were the file size for sending by email, the simplicity of setup and use, the visual attractiveness and a quick visualization of results. The tool consists of two Excel files coupled with a database which permits to send a daily email to the operator with the functioning state of each measurement point. However, the tool does not do everything, human analysis is necessary to have a critical eye on the results and to decide when to trigger a cleaning operation.

    The main perspective at the end of this thesis is the replacement of the preventive cleaning operations that were previously performed with a fixed frequency per year by conditional cleaning operations triggered by the tool and to observe the decrease of cleaning operations. Other perspectives are to spread the tool to other sites and to use the received feedbacks to adjust the different parameters and eventually to determine an automatic trigger condition of cleaning operations.

  • 152. Herrmann, I.
    et al.
    Jourak, A.
    Gustafsson, Jon Petter
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. Department of Soil and Environment, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Hedström, A.
    Lundström, T. S.
    Viklander, M.
    Modeling phosphate transport and removal in a compact bed filled with a mineral-based sorbent for domestic wastewater treatment2013In: Journal of Contaminant Hydrology, ISSN 0169-7722, E-ISSN 1873-6009, Vol. 154, p. 70-77Article in journal (Refereed)
    Abstract [en]

    Phosphorus filter units containing mineral-based sorbents with a high phosphate (PO4) binding capacity have been shown to be appropriate for removing PO4 in the treatment of domestic wastewater in on-site facilities. However, a better understanding of their PO4 removal mechanisms, and reactions that could lead to the formation of PO4 compounds, is required to evaluate the potential utility of candidate sorbents. Models based on data obtained from laboratory-scale experiments with columns of selected materials can be valuable for acquiring such understanding. Thus, in this study the transport and removal of PO4 in experiments with a laboratory-scale column filled with a commercial silicate-based sorbent were modeled, using the hydro-geochemical transport code PHREEQC. The resulting models, that incorporated the dissolution of calcite, kinetic constrains for the dissolution of calcium oxide (CaO) and wollastonite (CaSiO3), and the precipitation of amorphous tricalcium phosphate, Ca3(PO 4)2, successfully simulated the removal of PO4 observed in the experiments.

  • 153. Holländer, H. M.
    et al.
    Bormann, H.
    Blume, T.
    Buytaert, W.
    Chirico, G. B.
    Exbrayat, J. -F
    Gustafsson, David
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Hölzel, H.
    Krausse, T.
    Kraft, P.
    Stoll, S.
    Blöschl, G.
    Flühler, H.
    Impact of modellers' decisions on hydrological a priori predictions2014In: Hydrology and Earth System Sciences, ISSN 1027-5606, E-ISSN 1607-7938, Vol. 18, no 6, p. 2065-2085Article in journal (Refereed)
    Abstract [en]

    In practice, the catchment hydrologist is often confronted with the task of predicting discharge without having the needed records for calibration. Here, we report the discharge predictions of 10 modellers - using the model of their choice - for the man-made Chicken Creek catchment (6 ha, northeast Germany, Gerwin et al., 2009b) and we analyse how well they improved their prediction in three steps based on adding information prior to each following step. The modellers predicted the catchment's hydrological response in its initial phase without having access to the observed records. They used conceptually different physically based models and their modelling experience differed largely. Hence, they encountered two problems: (i) to simulate discharge for an ungauged catchment and (ii) using models that were developed for catchments, which are not in a state of landscape transformation. The prediction exercise was organized in three steps: (1) for the first prediction the modellers received a basic data set describing the catchment to a degree somewhat more complete than usually available for a priori predictions of ungauged catchments; they did not obtain information on stream flow, soil moisture, nor groundwater response and had therefore to guess the initial conditions; (2) before the second prediction they inspected the catchment on-site and discussed their first prediction attempt; (3) for their third prediction they were offered additional data by charging them pro forma with the costs for obtaining this additional information. Hollander et al. (2009) discussed the range of predictions obtained in step (1). Here, we detail the modeller's assumptions and decisions in accounting for the various processes. We document the prediction progress as well as the learning process resulting from the availability of added information. For the second and third steps, the progress in prediction quality is evaluated in relation to individual modelling experience and costs of added information. In this qualitative analysis of a statistically small number of predictions we learned (i) that soft information such as the modeller's system understanding is as important as the model itself (hard information), (ii) that the sequence of modelling steps matters (field visit, interactions between differently experienced experts, choice of model, selection of available data, and methods for parameter guessing), and (iii) that added process understanding can be as efficient as adding data for improving parameters needed to satisfy model requirements.

  • 154. Hoppe, Sabina
    et al.
    Gustafsson, Jon Petter
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Borg, Hans
    Breitholtz, Magnus
    Can natural levels of Al influence Cu speciation and toxicity to Daphnia magna in a Swedish soft water lake?2015In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 138, p. 205-210Article in journal (Refereed)
    Abstract [en]

    It is well known that chemical parameters, such as natural organic matter (NOM), cation content and pH may influence speciation and toxicity of metals in freshwaters. Advanced bioavailability models, e.g. Biotic Ligand Models (BLMs), can use these and other chemical parameters to calculate site specific recommendations for metals in the aquatic environment. However, since Al is not an input parameter in the BLM v.2.2.3, used in this study, there could be a discrepancy between calculated and measured results in Al rich waters. The aim of this study was to evaluate if the presence of Al in a circumneutral (pH 6) soft humic freshwater, Lake St. Envättern, will affect the Cu speciation and thereby the toxicity to the cladoceran Daphnia magna. The results show a statistically significant increase in the free Cu2+ concentration with Al additions and that measured levels of Cu2+ significantly differed from BLM calculated levels of Cu2+. Furthermore, there was also a statistically significant elevated acute toxic response to D. magna at low additions of Al (10μg/L). However, since the large difference between calculated and measured Cu2+ resulted in a significant but minor (factor of 2.3) difference between calculated and measured toxicity, further studies should be conducted in Al rich soft waters to evaluate the importance of adding Al as an input parameter into the BLM software.

  • 155.
    Hoppe, Sabina
    et al.
    Stockholms Universitet.
    Gustafsson, Jon Petter
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Borg, Hans
    Stockholms Universitet.
    Breitholtz, Magnus
    Stockholms Universitet.
    Evaluation of current copper bioavailability tools for soft freshwaters in Sweden2015In: Ecotoxicology and Environmental Safety, ISSN 0147-6513, E-ISSN 1090-2414, Vol. 114, p. 143-149Article in journal (Refereed)
    Abstract [en]

    The Water Framework Directive (WFD) in Europe calls for an improved aquatic ecological status. Biotic ligand models (BLM) have been suggested as a possible tool assisting in the regulatory process. The aim of this study was therefore to investigate the applicability of BLM under the WFD to set environmental quality standards (EQS), in particular regarding copper in Swedish freshwaters of which many are softer than those used for model calibration. Three different BLMs, one acute and two chronic, were applied to water chemistry data from 926 lakes and 51 rivers (1530 data entries) and evaluated with respect to their calibration range for input parameters. In addition, the predicted no-effect concentration (PNEC) for copper was calculated. From the 1530 data entries, 750 ended up outside of the BLM calibration range, when looking at the chemical parameters Ca2+, alkalinity, pH and DOC, primarily due to low carbonate alkalinity. Furthermore, the calculated Cu PNECs were higher than the suggested Swedish limit for Cu (4 µg L−1) in surface waters for 98% and 99% of the cases concerning lakes and rivers, respectively. To conclude, our findings show that water chemical characteristics outside of the calibration ranges are quite common in Sweden and that the investigated models differ in how they calculate toxicity concerning Cu under these conditions. As a consequence, additional work is required to validate the BLMs by use of bioassays with representative species of soft waters. Such results will show if these models can be used outside of their calibration ranges and also which of the models that gives the most reliable results.

  • 156.
    Hyder, A. H. M. Golam
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Begum, S. A.
    Egiebor, N. O.
    Adsorption isotherm and kinetic studies of hexavalent chromium removal from aqueous solution onto bone char2015In: Journal of Environmental Chemical Engineering, ISSN 2213-3437, Vol. 3, no 2, p. 1329-1336Article in journal (Refereed)
    Abstract [en]

    The adsorption of hexavalent chromium [Cr(VI)] onto bone char was optimized as a function of pH, initial Cr(VI) concentration, and bone char dosage using aqueous solution in batch tests. The initial Cr(VI) concentrations were varied between 5 and 800 mg/L to investigate equilibrium, kinetics, and the adsorption isotherms. About 100% of Cr(VI) was removed at initial pH of 1.0 with initial Cr(VI) concentration of 10 mg/L, using 2 g of bone char after 2 h. The maximum adsorption capacity of the bone char was 4.8 mg/g for an initial Cr(VI) concentration of 800 mg/L. The adsorption kinetics of Cr(VI) onto bone char followed a second order kinetic model. The adsorption isotherm followed the Langmuir model for Cr(VI) adsorption. In general, bone char demonstrated promising results as an effective adsorbent for removal of Cr(VI) from the aqueous solution. The results from this study could be useful in designing a filtration unit with bone char as the adsorbent in a full-scale water and wastewater treatment plant for the removal of Cr(VI) from contaminated water.

  • 157.
    Hyder, A. H. M. Golam
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Begum, Shamim A.
    Egiebor, Nosa O.
    Sorption studies of Cr(VI) from aqueous solution using bio-char as an adsorbent2014In: Water Science and Technology, ISSN 0273-1223, E-ISSN 1996-9732, Vol. 69, no 11, p. 2265-2271Article in journal (Refereed)
    Abstract [en]

    The characteristics of sorption of hexavalent chromium (Cr(VI)) onto bio-char derived from wood chips (spruce, pine, and fir) were evaluated as a function of pH, initial Cr(VI) concentration and bio-char dosage using synthetic wastewater in batch tests. The initial Cr(VI) concentrations were varied between 10 and 500 mg/L to investigate equilibrium, kinetics, and isotherms of the sorption process. About 100% of Cr(VI) was removed at pH 2 with initial Cr(VI) concentration of 10 mg/L using 4 g of bio-char after 5 hours of sorption reaction. The maximum sorption capacity of the bio-char was 1.717 mg/g for an initial Cr(VI) concentration of 500 mg/L after 5 hours. The sorption kinetics of total Cr onto bio-char followed the second-order kinetic model. The Langmuir isotherm model provided the best fit for total Cr sorption onto bio-char. The bio-char used is a co-product of a down draft gasifier that uses the derived syngas to produce electricity. Bio-char as a low cost adsorbent demonstrated promising results for removal of Cr(VI) from aqueous solution. The findings of this study would be useful in designing a filtration unit with bio-char in a full-scale water and wastewater treatment plant for the Cr(VI) removal from contaminated waters.

  • 158. Islam, A. B. M. R.
    et al.
    Maity, J. P.
    Bundschuh, Jochen
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Chen, C. -Y
    Bhowmik, B. K.
    Tazaki, K.
    Arsenic mineral dissolution and possible mobilization in mineral-microbe-groundwater environment2013In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 262, p. 989-996Article in journal (Refereed)
    Abstract [en]

    Arsenic (As) is widely distributed in the nature as ores or minerals. It has been attracted much attention for the global public health issue, especially for groundwater As contamination. The aim of this study was to elucidate the characteristics of microbes in groundwater where As-minerals were dissolved. An ex situ experiment was conducted with 7 standard As-minerals in bacteria-free groundwater and stored in experimental vessels for 1 year without supplementary nutrients. The pH (6.7-8.4) and EhS.H.E. (24-548mV) changed between initial (0 day) and final stages (365 days) of experiment. The dissolution of As was detected higher from arsenolite (4240±8.69mg/L) and native arsenic (4538±9.02mg/L), whereas moderately dissolved from orpiment (653±3.56mg/L) and realgar (319±2.56mg/L) in compare to arsenopyrite (85±1.25mg/L) and tennantite (3±0.06mg/L). Optical microscopic, scanning electron microscopic observations and flurometric enumeration revealed the abundance of As-resistant bacillus, coccus and filamentous types of microorganisms on the surface of most of As-mineral. 4'-6-Diamidino-2-phenylindole (DAPI)-stained epifluorescence micrograph confirmed the presence of DNA and carboxyfluorescein diacetate (CFDA) staining method revealed the enzymatically active bacteria on the surface of As-minerals such as in realgar (As4S4). Therefore, the microbes enable to survive and mobilize the As in groundwater by dissolution/bioweathering of As-minerals.

  • 159. Ivarsson, Anneli
    et al.
    Kinsman, John
    Johansson, Karin
    Mohamud, Khalif Bile
    Weinehall, Lars
    Freij, Lennart
    Wall, Stig
    Dalmar, Abdirisak Ahmed
    Ibrahim, Abdirashid Omer
    Hagi, Abdisamad Abikar
    Abdi, Abshir Ali
    Hussein, Abdullahi Sheik
    Shirwa, Abdulkadir Mohamed
    Warsame, Amina
    Ereg, Derie Ismail
    Aden, Mohamed Hussain
    Qasim, Maryan
    Ali, Mohamed Khalid
    Elmi, Abdullahi
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Afrah, Abdullahi Warsame
    Sabtiye, Faduma Omar
    Guled, Fatuma Ege
    Ahmed, Hinda Jama
    Mohamed, Halima
    Tinay, Halima Ali
    Mohamud, Kadigia Ali
    Yusuf, Mariam Warsame
    Omar, Mayeh
    Abdi, Yakoub Aden
    Abdulkadir, Yusuf
    Johansson, Annika
    Kulane, Asli Ali
    Schumann, Barbara
    Essen, Birgitta
    Kalengayi, Faustine Nkulu
    Elgh, Fredrik
    Norstrom, Fredrik
    Lonnberg, Goran
    Norder, Helene
    Schroders, Julia
    Erlandsson, Kerstin
    Edin, Kerstin
    Sahlen, Klas-Goran
    Gustafsson, Lars L.
    Persson, Lars-Ake
    Eriksson, Malin
    Emmelin, Maria
    Hasselberg, Marie
    Klingberg, Marie
    Preet, Raman
    Hogberg, Ulf
    Sjostrom, Urban
    Omar, Saif
    Healing the health system after civil unrest2015In: Global Health Action, ISSN 1654-9716, E-ISSN 1654-9880, Vol. 8, no 1, p. 1-4, article id 27381Article in journal (Refereed)
  • 160.
    Jacks, Gunnar
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Slejkovec, Zdenka
    Mörth, Magnus
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Redox-cycling of arsenic along the water pathways in sulfidic metasediment areas in northern Sweden2013In: Applied Geochemistry, ISSN 0883-2927, E-ISSN 1872-9134, Vol. 35, p. 35-43Article in journal (Refereed)
    Abstract [en]

    Arsenic has emerged as a problem element in groundwater. The most common mechanism of mobilising As from the solid phase into water is through the reductive dissolution of ferric oxyhydroxides. This investigation was made in northern Sweden where metasediments containing pyrite, pyrrhotite and arsenopyrite underlay about 4000 km(2). The overlying till contains as much as up to 100 mg kg (1) As. Speciation of the dissolved As shows that arsenite dominates largely over arsenate. The Fe oxyhydroxides formed may contain up to 0.5% As. Sandy sediments may contain 100-500 mg kg (1). Arsenic and Fe are closely correlated. The cycling of As in water, flora and fauna in wetlands has been studied. Ferric reduction occurs in wetlands and groundwater rich in Fe, and As is found to be discharging into ditches, brooks and streams. Wetland trees and plants show a moderately elevated content of As with a few species showing above 2 mg kg (1), the permissible level in fodder for domestic animals. The only plants having a high content of As are Equisetum species showing up to 26 mg kg (1). These plants make up a small fraction of the food of wild, grazing and browsing animals, for example moose and reindeer, and does not seem to constitute an environmental risk. However, the animals could be exposed to considerable amounts of As by drinking water from springs in wetlands. In the fauna, an elevated As content has so far been found in a limited number of benthic macroinvertebrate samples (1.23-42.1 mg kg (1) dry weight), in which inorganic As species (arsenate) predominate in the extractable fraction (62-82%) with lower amounts of arsenite, mono-and dimethylarsenic acid. Some samples also contained arsenobetaine, trimethylarsine oxide and tetramethylarsonium ion. To the authors' knowledge, this is the first report on As speciation in benthic macroinvertebrates. Fish species from polluted streams (pike and brown trout) had normal As levels (0.57-1.84 mg kg (1) dry weight), mainly present in a form of arsenobetaine (brown trout) or arsenobetaine and dimethylarsinic acid (pike). As both fish species also contained minor amounts of arsenite and arsenate, it is estimated that there is no serious health risk to potential consumers.

  • 161.
    Jacks, Gunnar
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Thambi, D. S. C.
    Groundwater Memories of Past Climate Change-Examples from India and the Nordic Countries2017In: JOURNAL OF CLIMATE CHANGE, ISSN 2395-7611, Vol. 3, no 1, p. 49-57Article in journal (Refereed)
    Abstract [en]

    The last glacial period can be identified in groundwater globally in hydrochemistry and groundwater turnover. To illustrate this, three examples representing very different conditions are presented here, two from India and one from the Nordic countries. The last glacial period resulted in a 125 m lowering of the sea level below present level and the return to the same level within a relatively short geological time span. The low sea water level at Last Glacial Maximum (LGM) induced, in combination with variations in the SW monsoon, recharge of coastal aquifers here exemplified by the Tertiary aquifers in Kerala. The sea level lowering before LGM and its rapid subsequent recovery after LGM has caused different sedimentation conditions resulting in more oxidised Pleistocene sediments compared to Holocene sediments. This has affected the redox conditions and resulted in mobilisation of arsenic in groundwater in the Holocene strata notably in the Bengal delta and upstreams in the Ganga valley. In the Nordic countries there was a 2.0-2.5 km high load of ice on the land. The result of the melting is seen in land uplift, which is still active to this day. The connections between the Baltic Sea and the ocean via the North Sea has varied during the postglacial period resulting in brackish and fresh water conditions making their imprint in the hydrochemistry and turnover of the groundwater. A common feature is seen from both regions in the form of the Na-HCO3 type of groundwater formed during fresh water flushing of a formerly saline aquifer. Along some shorelines there are reducing environment similar to those in India but the main manifestation is acid drainage as a result of slow land uplift and drainage for agriculture.

  • 162.
    Jacks, Gunnar
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Traoré, M. S.
    Mechanisms and rates of groundwater recharge at Timbuktu, Republic of mali2014In: Journal of hydrologic engineering, ISSN 1084-0699, E-ISSN 1943-5584, Vol. 19, no 2, p. 422-427Article in journal (Refereed)
    Abstract [en]

    The mechanisms and the rate of groundwater recharge were assessed for the uppermost aquifer used for water supply by local settlements in the area surrounding Timbuktu, Republic of Mali, using chloride budgets. The area receives a mean rainfall of 225 mm annually. Three clusters of wells and three soil water profiles were sampled for the study. The well cluster in the vicinity of the River Niger showed effects of induced infiltration via an active wetland fed by the old canal, which once connected Timbuktu with the River Niger. For the well clusters further away from the river, an annual mean recharge of 4 mm was found. A similar recharge, 1-2% of the precipitation, was found by assessing the recharge from the soil water chloride in three pits dug to 2.2-m depth. The recharge occurs preferably in depressions between dunes and due to channeling by soil crusts on the slopes of the dunes. This runoff-runon regime is probably the mechanism that allows any recharge to occur at all. The depressions, called mares in French, have standing water for extended periods after the rainy season, which is mirrored by gley patches in the subsoil. Occasional high nitrate concentrations in soil profiles indicate that conditions for nitrification and nitrate leaching occur after long drought periods followed by onset of heavy rain. This is a witness of the large variability of the precipitation climate in time and space, also mirrored in the variations of the figures for groundwater recharge. The moist conditions give growth to cyano-bacteria found on the soil surface in the mares. N-fixation by cyano-bacteria is probably the reason for occasional very high nitrate contents in soil and groundwater. The water demand by the local settlements has been assessed by using figures for population and livestock density and their water use. The water demand by the local population and their herds is sustainable in relation to the groundwater recharge assessed by this study.

  • 163. Jaime Gomez-Hernandez, J.
    et al.
    Butler, James. J.
    Fiori, Aldo
    Bolster, Diogo
    Cvetkovic, Vladimir
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Dagan, Gedeon
    Hyndman, David
    Introduction to special section on Modeling highly heterogeneous aquifers: Lessons learned in the last 30 years from the MADE experiments and others INTRODUCTION2017In: Water resources research, ISSN 0043-1397, E-ISSN 1944-7973, Vol. 53, no 4, p. 2581-2584Article in journal (Refereed)
  • 164.
    Jamali, Imran Ali
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Subsurface dams in water resource management: methods for assessment and location2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Natural groundwater storage can be improved by constructing a subsurface barrier that is a subsurface dam, in order to capture the subsurface flows and raise the groundwater levels (GWLs) in the sediment layers. Subsurface dams are preferable to surface dams because of lower evaporation, higher functionality, lower cost of construction, lessened risk for contamination and the possibility of utilizing land over the dam. Therefore subsurface dams constitute an affordable and effective method for the sustainable development and management of groundwater resources. The aim of this research project was to develop and test methods for the assessment and location of subsurface dams in water resources management. From previous experiences it has been established that locating suitable sites for construction of subsurface dams plays an important role in the overall success of these dams. Therefore, in order to locate suitable sites, two approaches were followed. The first was the Boolean approach using topographical, geological and landcover data in a geographic information system (GIS) environment for a previously glaciated terrain near Stockholm. The results of the Boolean approach were complemented by a groundwater balance model and a topographic wetness index (TWI). The second approach involved spatial multi-criteria analysis (SMCA) applied to a region with different geological and hydrological conditions. SMCA was applied in Northern Pakistan using factors such as topography, geology, landcover, soil thickness and TWI. Two weighting techniques, the analytic hierarchy process (AHP) and the factor interaction method (FIM), were employed and compared. The Factor removal technique was employed to assess the sensitivity of the model for each factor. Aquifer thickness is an important factor while planning subsurface dams and data regarding the soil thickness is often not available at larger scale. Therefore a simplified regolith model (SRM) was developed for estimating the regolith thickness in previously glaciated terrain with a high frequency of rock outcrops, based on a digital elevation model (DEM) and an optimized outcrop search algorithm. In order to analyse the dynamics of the groundwater flow, a transient 3D groundwater flow model was developed for a subsurface dam. Methods applied to locate suitable sites for the construction of subsurface dams showed some promising results and need to be applied and tested in areas with different hydrological and geological conditions. The Boolean approach is a simple method that could be used during early planning stages for locating suitable sites for the construction of subsurface dams. The SMCA framework enabled the integration of knowledge for decision making, where the weights had a more significant influence on the results than the choice of the weighting method. AHP was considered to be the more robust model for assigning weights in this study. The factor removal technique showed that the modeling results were least sensitive to soil depth and most sensitive to land cover for the construction of subsurface dams. SRM showed reasonable results and could be used in engineering projects prior to detailed field investigations in formally glaciated terrain when borehole data is not available. The groundwater flow modelling results helped to develop some sustainable pumping scenarios to demonstrate the benefits of the subsurface dam. Groundwater flow model results also facilitated the selection of a suitable site for placing a subsurface dam in order to maximize the groundwater storage upstream. It was concluded in this project that the subsurface dams could sustainably be used to mitigate the water supply issues in formerly glaciated humid terrain such as in Sweden and dry climatic areas such as in Pakistan. Moreover, subsurface dams can play an important role in water resources management in coastal areas of formerly glaciated terrain, where saltwater intrusion is a rising environmental issue. Also in dry climatic areas like in Pakistan, methods such as SMCA could make the planning step more robust before the actual construction of dams. Themethods and findings presented in this thesis can be considered to be one tentative step of scientific contribution for better analysis, assessment and the location of subsurface dams.

  • 165.
    Jamali, Imran Ali
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Dehkordi, Seyed Emad
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Olofsson, Bo
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Zou, Liangchao
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Groundwater flow model of a subsurface dam at Lillsved, Stockholm, SwedenManuscript (preprint) (Other academic)
  • 166.
    Jamali, Imran Ali
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Mörtberg, Ulla
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Management and Assessment.
    Olofsson, Bo
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Shafique, M
    A spatial multi-criteria analysis approach for locating suitable sites for construction of subsurface dams in northern Pakistan2014In: Water resources management, ISSN 0920-4741, E-ISSN 1573-1650, Vol. 28, no 14, p. 5157-5174Article in journal (Refereed)
    Abstract [en]

    Pakistan is an agricultural country with an increasing interest for hydropower. Water management problems such as sedimentation and evaporation have been of high concern for surface water reservoirs for many years. Therefore, groundwater storage through subsurface dams could be promising, especially considering the monsoon rainfall and seasonal river flows in Pakistan. The paper aims to develop and test a methodology to locate suitable sites for construction of subsurface dams using spatial multi-criteria analysis (SMCA) in the northern parts of Pakistan. For the study, spatial data on geology, slope, land cover, soil depth and topographic wetness index (TWI) was used. Two weighting techniques, i.e. the analytic hierarchy process (AHP) and the factor interaction method (FIM), were employed and compared. The sensitivity of the two methods as well as of the model parameters was analysed. The suitability map derived from AHP yielded about 3 % (16 km(2)) of the total area as most suitable, about 4 % (22 km(2)) as moderately suitable and about 0.8 % (5 km(2)) as least suitable. The suitability map derived from FIM identified about 2.7 % (14 km(2)) of the total area as most suitable, about 4 % (22 km(2)) as moderately suitable and about 1 % (7 km(2)) as least suitable. The sensitivity analyses suggested that AHP was a more robust weighting technique than FIM and that land cover was the most sensitive factor. The methodology presented here shows promising results and could be used in early planning to locate suitable sites for construction of subsurface dams.

  • 167.
    Jamali, Imran Ali
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Olofsson, Bo
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Mörtberg, Ulla
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Locating suitable sites for the construction of subsurface dams using GIS2013In: Environmental Earth Sciences, ISSN 1866-6280, Vol. 70, no 6, p. 2511-2525Article in journal (Refereed)
    Abstract [en]

    Subsurface dams constitute an affordable and effective method for the sustainable development and management of groundwater resources when constructed on suitable sites. Such dams have rarely been constructed in crystalline rock areas and to best of our knowledge, geographic information system (GIS) has never been used in any methodology for locating suitable sites for constructing these dams. This paper presents a new methodology to locate suitable sites for the construction of subsurface dams using GIS software supported by groundwater balance modelling in a study area Boda-Kalvsvik, Sweden. Groundwater resources were calculated based on digitized geological data and assumptions regarding stratigraphic layering taken from well archive data and geological maps. These estimates were then compared with future extractions for domestic water supply using a temporally dynamic water balance model. Suitability analyses for subsurface dams were based on calculated topographic wetness index (TWI) values and geological data, including stratigraphic information. Groundwater balance calculations indicated that many of the most populated areas were susceptible to frequent water supply shortages. Of the 34 sub-catchments within the study area: ten were over-extracted, nine did not have any water supply demand at all, one was self-sufficient and the remaining 14 were able to meet the water supply demand with surplus storage capacity. Six suitable sites for the construction of subsurface dams were suggested in the vicinity of the over-extracted sites based on suitability analysis and groundwater balance estimates. The new methodology shows encouraging results for regions with humid climate but having limited natural water storage capacities. The developed methodology can be used as a preliminary planning step for subsurface dam construction, establishing a base for more detailed field investigations.

  • 168.
    Jansson, Jessica
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Tungmetaller i Bolidens spillvattenledningsnät - Identifiering av områden med höga metallhalter samt tänkbara källor.2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Åtminstone sedan början av 1980-talet har det varit känt att höga metallhalter förekommer i spillvattnet i gruvorten Boliden. Skellefteå kommun som ansvarar för driften av Bolidens avloppsreningsverk (ARV) vill försöka minska metallhalterna i vattnet eftersom slammet från reningsverket innehåller så höga tungmetallhalter att det måste tas om hand lokalt. Detta examensarbete syftar därför till att identifiera i vilka områden i spillvattennätet det förekommer höga metallhalter och vad orsaken till detta är.

    Resultaten från stickprover tagna i spillvattennätet visar att kadmium (Cd) och zink (Zn) förekommer i halter som är 14 gånger högre än kommunens tillåtna varningsvärden samt att koppar (Cu) förekommer i halter som är 5 gånger högre än det tillåtna varningsvärdet i den norra äldsta delen av Boliden.

    Gruvverksamheten som har ägt rum i området sedan 1920-talet identifieras som den största föroreningskällan. Sulfidhaltigt gruvavfall som lakar Cd, Cu och Zn har använts vid uppbyggnaden av de äldsta norra delarna av Boliden. På grund av att  pillvattenledningsnätet idag är gammalt och av dålig kvalitet förekommer därför ett stort inläckage av vatten med höga halter av dessa metaller i de norra delarna av samhället, vilket leder till att slammet från Bolidens ARV får ett högt innehåll av framförallt Cd och Zn.

  • 169.
    Juston, John
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Jansson, Per-Erik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Gustafsson, David
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Rating curve uncertainty and change detection in discharge time series: Case study with 44-year historic data from the Nyangores River, Kenya2014In: Hydrological Processes, ISSN 0885-6087, E-ISSN 1099-1085, Vol. 28, no 4, p. 2509-2523Article in journal (Refereed)
    Abstract [en]

    The intersection of the developing topic of rating curve and discharge series uncertainty with the topic of hydrological change detection (e.g., in response to land cover or climatic change) has not yet been well studied. The work herein explores this intersection, with consideration of a long-term discharge response (1964-2007) for a ~650-km2 headwater basin of the Mara River in west Kenya, starting with stream rating and daily gauge height data. A rating model was calibrated using Bayesian methods to quantify uncertainty intervals in model parameters and predictions. There was an unknown balance of random and systemic error in rating data scatter (a scenario not likely unique to this basin), which led to an unknown balance of noise and information in the calibrated statistical error model. This had implications on testing for hydrological change. Overall, indications were that shifts in basin's discharge response were rather subtle over the 44-year period. A null hypothesis for change using flow duration curves (FDCs) from four different 8-year data intervals could be either accepted or rejected over much of the net flow domain depending on different applications of the statistical error model (each with precedence in the literature). The only unambiguous indication of change in FDC comparisons appeared to be a reduction in lowest baseflow in recent years (flows with >98% exceedance probability). We defined a subjective uncertainty interval based on an intermediate balance of random and systematic error in the rating model that suggested a possibility of more prevalent impacts. These results have relevance to management in the Mara basin and to future studies that might establish linkages to historic land use and climatic factors. The concern about uncertain uncertainty intervals (uncertainty2) extends beyond the Mara and is relevant to testing change where non-random rating errors may be important and subtle responses are investigated.

  • 170.
    Jutebring Sterte, Elin
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Integrated hydrologic flow characterization of the Krycklan catchment (Sweden).2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Currently there are urgent water related problems, such as use of groundwater and surface water resources, which need a more integrated view on the hydraulic cycle and how the different processes interact with each other. This has led to new ways of thinking in management of watersheds, which sparked the creation of new integrated tools for flow characterization. Characterization of a watersheds flow is an important step in future research regarding water quality and climate change issues.

    The Krycklan catchment, located in the northern part of Sweden, has been under research for many years. With a great deal of measurements regarding stream water chemistry as well as climate measurements (evaporation, transpiration and temperature), the catchment has great potential regarding solute transportation and climate change investigation.

    This thesis was made to aid in future research by characterization of the catchments groundwater and surface flow, by the use of an integrated model software tool, MIKE-SHE. The model have been calibrated and validated with the help of real time observed measurements at Krycklan combined with model data from SMHI:s HYPE-model. Throughout the calibration it was discovered that the hydraulic conductivities were important for the surface and groundwater interaction, regulating base flow as well as peak flows. The shape and timing of the spring flood was also affected by the snow melt while the summer peaks for the upstream rivers, probably due to the relatively large difference in topography elevation, were more affected by the representation of the topography created by the grid size.

    A smaller grid-size resulted in a finer representation of the topography, which resulted in a quicker runoff to the upstream rivers without an increase of base flow. This gave better fitted hydrographs of the flows in the upstream rivers compared to observed measurements. The final model created was able to capture the discharge-hydrograph and groundwater fluctuations with small error and high correlation coefficients compared to observed data and model data from SMHI.

    The results as well as the calibration process helped with a deeper understanding of the modeling tool itself as well. Future improvements that can be considered are to introduce new calibration data and the use of an even smaller grid size. This can improve the understanding of the catchment as well as the representation of the flow in the upstream rivers. However, the effects of a smaller grid size must be reflected upon. The model will most likely become more unstable and the run time of the model will greatly increase. One suggestion to solve this issue is to look into a sub-catchment to reduce these complications.

  • 171. Jyväsjärvi, J.
    et al.
    Marttila, H.
    Rossi, P. M.
    Ala-Aho, P.
    Olofsson, Bo
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Nisell, J.
    Backman, B.
    Ilmonen, J.
    Virtanen, R.
    Paasivirta, L.
    Britschgi, R.
    Kløve, B.
    Muotka, T.
    Climate-induced warming imposes a threat to north European spring ecosystems2015In: Global Change Biology, ISSN 1354-1013, E-ISSN 1365-2486, Vol. 21, no 12, p. 4561-4569Article in journal (Refereed)
    Abstract [en]

    Interest in climate change effects on groundwater has increased dramatically during the last decade. The mechanisms of climate-related groundwater depletion have been thoroughly reviewed, but the influence of global warming on groundwater-dependent ecosystems (GDEs) remains poorly known. Here we report long-term water temperature trends in 66 northern European cold-water springs. A vast majority of the springs (82%) exhibited a significant increase in water temperature during 1968-2012. Mean spring water temperatures were closely related to regional air temperature and global radiative forcing of the corresponding year. Based on three alternative climate scenarios representing low (RCP2.6), intermediate (RCP6) and high-emission scenarios (RCP8.5), we estimate that increase in mean spring water temperature in the region is likely to range from 0.67 °C (RCP2.6) to 5.94 °C (RCP8.5) by 2086. According to the worst-case scenario, water temperature of these originally cold-water ecosystems (regional mean in the late 1970s: 4.7 °C) may exceed 12 °C by the end of this century. We used bryophyte and macroinvertebrate species data from Finnish springs and spring-fed streams to assess ecological impacts of the predicted warming. An increase in spring water temperature by several degrees will likely have substantial biodiversity impacts, causing regional extinction of native, cold-stenothermal spring specialists, whereas species diversity of headwater generalists is likely to increase. Even a slight (by 1 °C) increase in water temperature may eliminate endemic spring species, thus altering bryophyte and macroinvertebrate assemblages of spring-fed streams. Climate change-induced warming of northern regions may thus alter species composition of the spring biota and cause regional homogenization of biodiversity in headwater ecosystems.

  • 172.
    Kalantari, Zahra
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Road structures under climate and land use change: Bridging the gap between science and application2014Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Future changes in climate and land use are likely to affect catchment hydrological responses and consequently influence the amount of runoff reaching roads. Blockages and damage to under-dimensioned infrastructure can be extremely costly for the regions affected. This study aims to produce scientifically well-founded suggestions on adaptation of road drainage systems to climate changes resulting in more frequent floods. This thesis demonstrates the need to integrate aspects of climate change and land use impacts into the planning and practice of road construction and maintenance in Sweden. Tools such as hydrological models are needed to assess impacts on discharge dynamics. Identifying a ‘best’ practically performing hydrological model is often difficult due to the potential influence of modeller subjectivity on calibration procedure, parameter selection, etc. Hydrological models may need to be selected on a case-by-case basis and have their performance evaluated on an application-by-application basis.

    The work presented here began by examining current practice for road drainage systems in Sweden. Various hydrological models were then used to calculate the runoff from a catchment adjacent to a road and estimate changes in peak discharge and total runoff resulting from simulated land use measures. Overall, the results indicate that the specific effect of land use measures on catchment discharge depend on their spatial distribution and on the size and timing of storm events. Scenarios comprising a changing climate up to 2050 or to 2100 and forest clear-cutting were used to determine whether the current design of road drainage construction is sufficient for future conditions. Based on the findings, the approach developed can be used for similar studies, e.g. by the Swedish Transport Administration in dimensioning future road drainage structures to provide safe and robust infrastructure.

    Furthermore, a statistical method was developed for estimating and mapping flood hazard probability along roads using road and catchment characteristics. The method allows flood hazards to be estimated and provides insight into the relative roles of landscape characteristics in determining road-related flood hazards. Overall, this method provides an efficient way to estimate flooding hazards and to inform the planning of future roadways and the maintenance of existing roadways.

  • 173.
    Kalantari, Zahra
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Briel, Annemarie
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Lyon, Steve W.
    Olofsson, Bo
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Folkeson, Lennart
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    On the utilization of hydrological modelling for road drainage design under climate and land use change2014In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 475, no 15, p. 97-103Article in journal (Refereed)
    Abstract [en]

    Road drainage structures are often designed using methods that do not consider process-based representations of a landscape's hydrological response. This may create inadequately sized structures as coupled land cover and climate changes can lead to an amplified hydrological response. This study aims to quantify potential increases of runoff in response to future extreme rain events in a 61 km2 catchment (40% forested) in southwest Sweden using a physically-based hydrological modelling approach. We simulate peak discharge and water level (stage) at two types of pipe bridges and one culvert, both of which are commonly used at Swedish road/stream intersections, under combined forest clear-cutting and future climate scenarios for 2050 and 2100. The frequency of changes in peak flow and water level varies with time (seasonality) and storm size. These changes indicate that the magnitude of peak flow and the runoff response are highly correlated to season rather than storm size. In all scenarios considered, the dimensions of the current culvert are insufficient to handle the increase in water level estimated using a physically-based modelling approach. It also appears that the water level at the pipe bridges changes differently depending on the size and timing of the storm events. The findings of the present study and the approach put forward should be considered when planning investigations on and maintenance for areas at risk of high water flows. In addition, the research highlights the utility of physically-based hydrological models to identify the appropriateness of road drainage structure dimensioning.

  • 174. Kalantari, Zahra
    et al.
    Khoshkar, Sara
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Falk, Helena
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Cvetkovic, Vladimir
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Mörtberg, Ulla
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Accessibility of water-related cultural ecosystem services through public transport: A model for planning support in the Stockholm Region2017In: Sustainability, ISSN 2071-1050, E-ISSN 2071-1050, Vol. 9, no 3, p. 346-Article in journal (Refereed)
    Abstract [en]

    Planning for sustainable cities involves supporting compact, energy-efficient urban form as well as maintaining attractive and liveable urban landscapes. Attractive cities depend highly on services provided by ecosystems, especially cultural ecosystem services (ES), which give direct benefits to urban citizens. Therefore, access to a diversity of urban functions and publicly available ES by walking and public transport should be considered when planning for sustainable cities. This could be facilitated by user-friendly planning support models. The aim of this study was to develop a GIS-based model for assessing accessibility to ES, more specifically, water-related cultural ecosystem services (WCES), via walking and public transport, with input from stakeholders. The model was applied to the Stockholm region in Sweden. Travel times and census data were used to derive measures and maps of accessibility to prioritised WCES in the region, today and in urbanisation scenarios for 2050. The results showed how access to WCES varied spatially within the region. The number of potential visitors to different WCES sites now and in the future urbanisation scenarios was estimated, and areas in need for future development of the public transport system as well as WCES were identified. The GIS-based accessibility model has potential to be used as planning support in urban planning.

  • 175.
    Kalantari, Zahra
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Lyon, Stve W.
    Folkeson, Lennart
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    French, Helen K.
    Stolte, Jannes
    Jansson, Per-Erik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Sassner, Mona
    Quantifying the hydrological impact of simulated changes in land use on peak discharge in a small catchment2014In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 466-467, p. 741-754Article in journal (Refereed)
    Abstract [en]

    A physically-based, distributed hydrological model (MIKE SHE) was used to quantify overland runoff in response to four extreme rain events and four types of simulated land use measure in a catchment in Norway. The current land use in the catchment comprises arable lands, forest, urban areas and a stream that passes under a motorway at the catchment outlet. This model simulation study demonstrates how the composition and configuration of land use measures affect discharge at the catchment outlet differently in response to storms of different sizes. For example, clear-cutting on 30% of the catchment area produced a 60% increase in peak discharge and a 10% increase in total runoff resulting from a 50-year storm event in summer, but the effects on peak discharge were less pronounced during smaller storms. Reforestation of 60% of the catchment area was the most effective measure in reducing peak flows for smaller (2-, 5- and 10-year) storms. Introducing grassed waterways reduced water velocity in the stream and resulted in a 28% reduction in peak flow at the catchment outlet for the 50-year storm event. Overall, the results indicate that the specific effect of land use measures on catchment discharge depends on their spatial distribution and on the size and timing of storm events.

  • 176.
    Kalantari, Zahra
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. Stockholm University, Sweden .
    Lyon, Stve W.
    Jansson, Per-Erik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Stolte, Jannes
    French, Helen K.
    Folkeson, Lennart
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Sassner, Mona
    Modeller subjectivity and calibration impacts on hydrological model applications: An event-based comparison for a road-adjacent catchment in south-east Norway2015In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 502, p. 315-329Article in journal (Refereed)
    Abstract [en]

    Identifying a 'best' performing hydrologic model in a practical sense is difficult due to the potential influences of modeller subjectivity on, for example, calibration procedure and parameter selection. This is especially true for model applications at the event scale where the prevailing catchment conditions can have a strong impact on apparent model performance and suitability. In this study, two lumped models (CoupModel and HBV) and two physically-based distributed models (LISEM and MIKE SHE) were applied to a small catchment upstream of a road in south-eastern Norway. All models were calibrated to a single event representing typical winter conditions in the region and then applied to various other winter events to investigate the potential impact of calibration period and methodology on model performance. Peak flow and event-based hydrographs were simulated differently by all models leading to differences in apparent model performance under this application. In this case study, the lumped models appeared to be better suited for hydrological events that differed from the calibration event (i.e., events when runoff was generated from rain on non-frozen soils rather than from rain and snowmelt on frozen soil) while the more physical-based approaches appeared better suited during snowmelt and frozen soil conditions more consistent with the event-specific calibration. This was due to the combination of variations in subsurface conditions over the eight events considered, the subsequent ability of the models to represent the impact of the conditions (particularly when subsurface conditions varied greatly from the calibration event), and the different approaches adopted to calibrate the models. These results indicate that hydrologic models may not only need to be selected on a case-by-case basis but also have their performance evaluated on an application-by-application basis since how a model is applied can be equally important as inherent model structure.

  • 177.
    Kalantari, Zahra
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Nickman, Alireza
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Lyon, Steve W.
    Olofsson, Bo
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Folkeson, Lennart
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    A method for mapping flood hazard along roads2014In: Journal of Environmental Management, ISSN 0301-4797, E-ISSN 1095-8630, Vol. 133, p. 69-77Article in journal (Refereed)
    Abstract [en]

    A method was developed for estimating and mapping flood hazard probability along roads using road and catchment characteristics as physical catchment descriptors (PCDs). The method uses a Geographic Information System (GIS) to derive candidate PCDs and then identifies those PCDs that significantly predict road flooding using a statistical modelling approach. The method thus allows flood hazards to be estimated and also provides insights into the relative roles of landscape characteristics in determining road-related flood hazards. The method was applied to an area in western Sweden where severe road flooding had occurred during an intense rain event as a case study to demonstrate its utility. The results suggest that for this case study area three categories of PCDs are useful for prediction of critical spots prone to flooding along roads: i) topography, ii) soil type, and iii) land use. The main drivers among the PCDs considered were a topographical wetness index, road density in the catchment, soil properties in the catchment (mainly the amount of gravel substrate) and local channel slope at the site of a road-stream intersection. These can be proposed as strong indicators for predicting the flood probability in ungauged river basins in this region, but some care is needed in generalising the case study results other potential factors are also likely to influence the flood hazard probability. Overall, the method proposed represents a straightforward and consistent way to estimate flooding hazards to inform both the planning of future roadways and the maintenance of existing roadways.

  • 178.
    Kalantari, Zahra
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Sassner, Mona
    DHI Sverige AB.
    Assessing hydrological impact of land-use measures on peak discharge and total runoff2013In: Climate And Land Surface Changes In Hydrology, IAHS Press, 2013, p. 385-389Conference paper (Refereed)
    Abstract [en]

    Climate change may lead to an increase in the frequency of extreme precipitation events and floods as well as changes in frost/thaw cycles. This will have impacts on the performance and life time of road infrastructures. The frequency of road closures and other incidences will probably increase. The aim of this study is to to evaluate the effect of simulated land-use measures on the local hydrological response changes of a catchment near a low-lying road. The simulated land-use measures in this paper suggest different measures to reduce the generation of storm runoff on site and its delivery to the stream. The effect of these land-use measures on catchment discharge is dependent on the size and time of storm events.

  • 179.
    Kale, Manoj Ashokrao
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Dudhe, Nandkishor
    Kasambe, Raju
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630).
    Crop Depredation by Birds in Deccan Plateau, India2014In: International Journal of Biodiversity, ISSN 2314-4149, E-ISSN 2314-4157, no 947683, p. 8-Article in journal (Refereed)
    Abstract [en]

    Extent of crop depredation in agricultural fields of groundnut, pearl millet, peas, sorghum and sunflower was assessed in Pune, Akola and Amravati, the three productive districts of Maharashtra, India. The study included interviews with the farmers, identification of the bird species responsible for the crop depredation and actual field assessment of damage.The problem of crop depredation is severe for the crops mostly during harvesting season. Most farmers were not satisfied with the conventional bird repelling techniques. Amaximum depredation was observed by Sorghum crops by house sparrows Passer domesticus, baya weavers Ploceus philippinus, and rose-ringed parakeets Psittacula krameri, accounting to 52%of the total damage. Blue rock pigeons Columba livia damaged 42% of the peas crop (chick peas and pigeon peas), while house sparrows and baya weaver damaged the roundnut crop by 26% in the sampling plots. House sparrow Passer domesticus and baya weaver Ploceus philippinus damaged the groundnut crop in the sampling plots just after the sowing period. The sustainable solution for reducing crop depredation is a need for the farmers and also such techniques will help avoid direct or indirect effects of use of lethal bird control techniques on bird species.

  • 180.
    Kale, Manoj
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Dudhe, Nandkishor
    Ferrante, Marco
    Kasambe, Raju
    Trukhanova, Irina
    Trofimova, Tatina
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Lövei, Gabor L.
    Analysis of bird assemblage structure along an urbanisation gradient in Central IndiaManuscript (preprint) (Other (popular science, discussion, etc.))
    Abstract [en]

    We censuses terrestrial bird assemblages along a five-stage urbanisation gradient (rural forest, industrial zone, periurban, suburban, urban abitats) in and around Amravati City, Central India between January and April 2010-2013. A total of 89 species of birds were recorded, with the highest species richness in the rural areas (67 species) and lowest in the urban one (29 species). The rural habitats had the highest diversity, followed, in a decreasing order, by industrial, periurban, suburban, and urban areas, supporting the increasing disturbance hypothesis rather than the medium disturbance hypothesis. The densities were, however, highest in the urban habitats, supporting the resource concentration hypothesis. The assemblages were significantly nested.

  • 181.
    Kale, Manoj
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Dudhe, Nandkishor
    Ferrante, Marco
    Kasambe, Raju
    Trukhanova, Irina
    Trofimova, Tatina
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Lövei, Gabro
    The effect of urbanisation on beta diversity and functional diversity of bird assemblages in Central IndiaManuscript (preprint) (Other academic)
    Abstract [en]

    Diversity changes can be evaluated at various spatial scales, and the relationship between changes in diversity at the local, landscape and regional scales is not evident. We evaluated overall patterns of functional and beta diversity of bird assemblages along a five-stage urbanisation gradient, censused over the months of January to April in the years 2010-2012, in and around Amravati City, Deccan Plateau, Central India. Along the urbanisation gradient, bird assemblages contained more and more small species, and the share of frugivorous and omnivorous species also increased, while that of zoophagous species decreased. Diversity partitioning indicated that of the overall pattern, local (alpha) diversity accounted for 50% of the total (gamma) diversity, and urbanisation stages another 36%; the contribution of within-stage, local diversity was rather small (2.7%), indicating fairly homogeneous assemblages.

  • 182.
    Kale, Manoj
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Dudhe, Nandkishor
    Kasambe, Raju
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Cropland bird community of rain fed region in India: Abundance, activity pattern and susceptibility topesticide use2013In: International Journal of Biodiversity and Conservation, ISSN 2141-243X, Vol. 5, no 10, p. 616-624Article in journal (Refereed)
    Abstract [en]

    The activities of cropland birds in an agricultural land are most likely unpredictable in the rain fedregion of Maharashtra, India, and therefore the exposure to risk of pesticides application by croplandbird species cannot be sufficiently categorized. The pattern of abundance, territorial, foraging and otheractivities of cropland avian species was examined at two croplands in Amravati District of MaharashtraState to distinguish the susceptibility of bird species to the application of pesticide use. Overall, 53 birdspecies were identified in the two croplands over two years period during 2011 and 2012, from June toDecember. However, out of 53 species, only 14 species were common (recorded at ≥50 of visits) in bothcroplands. Twenty-one (21) bird species were recorded at Zadgaon Cropland in crops of tur (Cajanuscajan), cotton (Gossypium arboreum) and soybean (Glycine max). Nineteen (19) bird species wererecorded at Bhankhed Cropland for more than 50% of visits in crops of jawar (Sorghum bicolor), cottonand mung (Phaseolus aureus). For Zadgaon cropland, territorial activity is most significant for fourspecies: house sparrow (Passer domesticus), jungle babbler (Turdoides striata), yellow-eyed babbler(Chrysomma sinense) and red-wattled Lapwing (Vanellus indicus). House sparrow and jungle babblerwere maximum, yellow-eyed babbler was less frequent but more than other species in the month ofJune, while red-wattled lapwing was maximum in the month of July. Foraging was the imperativeactivity for most of the species in all months: 24 to 49% of the birds in June; 41 to 61% of the birds inJuly; 63 to 90% of the birds in August; 77 to 97% of the birds in September; 57 to 97% of the birds inOctober; 66 to 98% of the birds in November and 74 to 97% of the birds in December. For Bhankhedcropland, foraging was significantly less for Ashy Prinia (Prinia socialis), Brahminy Myna (Sturniapagodarum) and Black Drongo (Dicrurus macrocercus) in the month of June. The application ofpesticides in croplands took place from June to August, which means four species were under highrisk, 13 species were at medium risk and eight species at low risk. The level and intensity of thisexposure depends on occurrence of types of species in both croplands. This study is significant torecognize crucial species that can be used for detailed study on exposure to pesticides used in cropland.

  • 183.
    Karbasi, Mojtaba
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Quantifying the impact of climate change on groundwater resources of Bascombe well conservation park area by estimating recharge rates.2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Access to surface water is limited in Australia and many regions rely on groundwater for all their water needs. Most of aquifers are already fully allocated and there is an increasing demand for more extraction. During drought, drop in rainfall can result in less recharge into groundwater system.

    Decrease in rainfall can cause direct and indirect impacts on groundwater. Drop in rainfall can result in less recharge into groundwater system. Moreover decreased rainfall can cause limited accessibility to surface water which results in increased demand for extraction.

    Understanding of groundwater recharge mechanism and quantifying how far climate change can influence groundwater, plays an important role for establishing sustainable extraction without causing any damage into environment.

    The CoupModel was selected as a tool to simulate groundwater behavior under different Scenarios. Model inputs are derived from actual observations, such as climatic data. Few assumptions were considered to conceptualize drainage system, such as soil hydraulic parameters, drainage system and evaporation procedure.

    The study period is 30 years between 1979 and 2008. Model was run for two 15-year periods to identify how far climate change can influence groundwater recharge in the study area.

    Eyre Peninsula area is highly dependent on groundwater for town water supply, Irrigation and industrial development. Therefore any science study would be definitely valuable for groundwater resource management of this area.

  • 184.
    Karlson, Mårten
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Road Ecology for Environmental Assessment2015Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Transport infrastructure is closely linked to several politically relevant sustainability issues, and since 1985 a formalized environmental assessment process is linked to planning and construction of new roads and railways in the EU (EU directives 85/337/EEC and 2001/42). The aim of the environmental assessment process is to think in advance; to identify, predict and evaluate significant environmental changes resulting from a proposed activity, in order to adjust the proposed activity accordingly and to avoid unnecessary and unexpected consequences. Biodiversity is a component of sustainable development that is in many ways affected by road and railway construction, but which has been challenging to fully account for within the environmental assessment process. This thesis presents four studies on the role of biodiversity in environmental assessment of road and railway plans and projects. Paper I presents the state of the art of road and railway impacts on ecological patterns and processes sustaining biodiversity, and reviews the treatment of biodiversity in a selection of environmental assessment reports from Sweden and the UK. Paper II presents a quantitative assessment of the impact of the Swedish road network on birds and mammals, and how fragmentation and road disturbance might affect a selection of ecological profiles. Paper III demonstrates how scientific models, data and knowledge can be mobilized for the design and evaluation of railway corridors, and Paper IV analyses how habitat connectivity, as a prerequisite of genetic exchange, relates to landscape composition and size and number of fauna passages. The results from Paper I show that road and railway impacts on biodiversity need to be addressed at every level of planning; from corridor alignment in the landscape to utilization and maintenance. The review of environmental assessment reports shows that the treatment of biodiversity in environmental assessment has improved over the years, but that problems with habitat fragmentation, connectivity and the spatial delimitation of the impact assessment study area remain. The results from Paper II identify natural grasslands and southern broadleaved forest, prioritized habitat types important for biodiversity, to most likely be highly affected by road impacts, and suggest road disturbance to have a high impact on overall habitat availability. The results from Paper III demonstrate how the landscape specific distribution of ecological and geological resources can be accounted for in railway corridor design, and potentially lead to more resource efficient outcomes with less impact on ecological processes. The results from Paper IV indicate that the several small fauna passages would increase connectivity more across a barrier than the construction of a single large. Effective barrier mitigation will also depend on the selection of focal species and the understanding of how the focal species perceive the landscape in terms of resistance to movement. This thesis demonstrates how quantitative assessment can benefit biodiversity impact analysis and address issues such as habitat connectivity and fragmentation, which have been difficult to account for in environmental assessment. It is recommended that biodiversity impact analysis moves towards an increasing use of quantitative methods and tools for prediction, evaluation and sensitivity analysis. Future challenges include verification and calibration of relevant spatial ecological models, and further integration of road ecology knowledge into road and railway planning.

  • 185.
    Karlson, Mårten
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Karlsson, Caroline
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Mörtberg, Ulla
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Olofsson, Bo
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Balfors, Berit
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Design and evaluation of railway corridors based on spatial ecological and geological criteria2016In: Transportation Research Part D: Transport and Environment, ISSN 1361-9209, E-ISSN 1879-2340, Vol. 46, p. 207-228Article in journal (Refereed)
    Abstract [en]

    Transport infrastructure is closely linked to several sustainability issues of main policy relevance, and significant impacts on biodiversity as well as resource use and construction costs relate to the corridor design and location in the landscape. The aim of this study was to develop methods for railway corridor planning, in which corridor design and location would be based on important ecological and geological sustainability criteria. The method, an MCA framework including both spatial and non-spatial MCA, was demonstrated on a railway planning proposition in an urbanising area north of Stockholm, Sweden. Alternative spatial alignments for 6 railway corridors were derived based on criteria representing biodiversity, resource efficiency and costs, developed from ecological and geological knowledge, data and models. The method identified a study area specific positive synergy between ecological and geological sustainability criteria. The evaluation part of the methodology could furthermore identify uncertainties in the input data and assumptions and conflicts between ecological criteria. In order to arrive at a well-informed decision support system, the criteria as well as the decision rules employed could be further elaborated. Other relevant sustainability issues would also need to be integrated, such as cultural landscapes, recreation, and other ecosystem services. Still, arriving at a corridor design informed by the ecological and geological conditions in the planned area, as demonstrated by this study, could improve the sustainability performance of transport infrastructure planning.

  • 186.
    Karlson, Mårten
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Mörtberg, Ulla
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    A spatial ecological assessment of fragmentation and disturbance effects of the Swedish road network2015In: Landscape and Urban Planning, ISSN 0169-2046, E-ISSN 1872-6062, Vol. 134, p. 53-65Article in journal (Refereed)
    Abstract [en]

    Transportation infrastructure has a wide range of effects on ecological processes, which result in both positive and negative impacts for biodiversity. However, the treatment of biodiversity in planning and environmental assessment have been criticized, especially regarding habitat loss and fragmentation effects, the low use of quantitative methods and that of assessments being descriptive rather than analytical and predictive. The aim of this study was to assess the impacts of the Swedish road network by spatial modelling of road effects, to explore potential impacts of fragmentation and disturbance effects of roads on habitat networks for selected ecological profiles, and to discuss the utility of applying quantitative methods for environmental assessment purposes. Habitat and landcover data was used for creating habitat networks for six ecological profiles. Fragmentation and disturbance effects were modelled in GIS and FRAGSTATS was used to quantify ecologically important landscape metrics on habitat amount and connectivity. The results showed that natural grasslands and southern broadleaved forest were substantially more exposed to road effects in Sweden, compared to old coniferous and trivial broadleaved forest. Furthermore, habitat loss was a main consequence of road effects, and forest species with high area demands were most prone to be adversely impacted. Suggestions on method development in order to increase the quality of the analysis methods for environmental assessment are discussed. The potential is seen as high for use of quantitative ecological methods to generate baseline environmental information as well as coarse predictions on likely consequences of development options, useful for environmental assessment.

  • 187.
    Karlson, Mårten
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Seiler, A.
    Mörtberg, Ulla
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    The effect of fauna passages and landscape characteristics on barrier mitigation successManuscript (preprint) (Other academic)
    Abstract [en]

    Transport infrastructure can impose significant barriers to movements to many, if not most terrestrial animals. Barrier effects can lead to increased isolation of wildlife populations, which in turn might have demographic effects and even increase genetic differentiation between neighbouring populations. This study attempted to clarify the role of fauna passages and generic landscape patterns for connectivity in fragmented landscapes, and to improve the theoretical basis for future experimental approaches to evaluate the effectiveness of barrier mitigation strategies. Specifically, the issue of whether it would be more effective to construct a single large rather than several small crossing structures (SLOSS) was addressed by this study. Three hypotheses were formulated on the relationship between habitat connectivity, as a prerequisite for genetic exchange, and habitat aggregation and contrast between habitat types. Random landscapes with different combinations of aggregation, contrast and number and size of fauna passages were created in a GIS. Connectivity was then quantified as a function of movement resistance using circuit theory and related methods, and measurements from the random landscapes were statistically analysed. The results indicate that in any landscape, it would be more effective to construct several small fauna passages instead of a single large one to mitigate the effect of a barrier. The level of aggregation appeared to have no influence per se on connectivity, and increasing the level of contrast increased the variance in the results. Results indicate that the effectiveness of a fauna passage will to a large extent rely on the location of a fauna passage relative to how the mitigation target species perceive the landscape in terms of contrast between different habitat types. A predefined interval between fauna passages could therefore result in highly ineffective mitigation, in a situation where a fauna passage would be located in habitat perceived as of high resistance. It is recommended that barrier effect mitigation strategies focus on the location and design of several small fauna passages rather than a single large one. Future research should focus on the development of dispersal and movement models for a set focal species that perceive a minimum degree of contrast between habitat types.

  • 188.
    Karlson, Mårten
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Seiler, Andreas
    Swedish University of Agricultural Sciences.
    Mörtberg, Ulla
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    The effect of fauna passages and landscape characteristics on barrier mitigation success2017In: Ecological Engineering: The Journal of Ecotechnology, ISSN 0925-8574, E-ISSN 1872-6992, Vol. 105, p. 211-220Article in journal (Refereed)
    Abstract [en]

    Transport infrastructure can impose significant barriers to movements to many, if not most terrestrial animals. Barrier effects can lead to increased isolation of wildlife populations, which in turn might have demographic effects and even increase genetic differentiation between neighbouring populations. This study attempted to clarify the role of fauna passages and generic landscape patterns for connectivity in fragmented landscapes, and to improve the theoretical basis for future experimental approaches to evaluate the effectiveness of barrier mitigation strategies. Specifically, the issue of whether it would be more effective to construct a single large rather than several small crossing structures (SLOSS) was addressed by this study. Three hypotheses were formulated on the relationship between habitat connectivity, as a prerequisite for genetic exchange, and habitat aggregation and contrast between habitat types. Random landscapes with different combinations of aggregation, contrast and number and size of fauna passages were created in a GIS. Connectivity was then quantified as a function of movement resistance using circuit theory and related methods, and measurements from the random landscapes were statistically analysed. The results indicate that in any landscape, it would be more effective to construct several small fauna passages instead of a single large one to mitigate the effect of a barrier. The level of aggregation appeared to have no influence per se on connectivity, and increasing the level of contrast increased the variance in the results. It is recommended that barrier effect mitigation strategies focus on the location and design of several small fauna passages rather than a single large one. Future research should focus on the development of dispersal and movement models for a set focal species. The effectiveness of increasing fauna passage dimensions above those of crossing structures that are evidently used by the intended species should also need more research.

  • 189.
    Karlsson, Caroline
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Geo-environmental considerations in transport infrastructure planning2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Transport infrastructure constitutes one of the key factors to a country’s economic growth. Investment in new transport infrastructure might cause potential environmental impacts, and if a project has several alternative corridors open for suggestion then each alternative corridor will have a different impact on the environment. The European Commission has stated that the natural resources are important to the quality of life. Therefore, the efficient use of resources will be a key towards meeting future climate change and reduction in greenhouse gas (GHG) emissions. This implies that in an evergrowing global society the resource efficiency as well as the choice of transport infrastructure corridor becomes even more important to consider. The aim of this research project was to contribute to early transport infrastructure planning by the development of methods for and implementation of easy understandable geological criteria and models for decision support. Moreover, the intention was to assess how geological information can be developed and extracted from existing spatial data and coupled with other areas of interest, such as ecology and life cycle assessment. It has previously been established that geological information plays an important role in transport infrastructure planning, as the geological characteristics of the proposed area as well as the possibilities of material use influences the project. Therefore, in order to couple geological information for early transport infrastructure planning, four studies (Paper I-IV) were undertaken where methods were developed and tested for the inclusion of geological information. The first study (Paper I) demonstate how optional road corridors could be evaluated using geological information of soil thickness, soil type and rock outcrops, bedrock quality and slope in combination with ecological information. The second study (Paper II) shows how geological information of soil thickness and stratigraphy can be combined with life cycle assessments (LCA) to assess the corresponding greenhouse gas emission and energy use for the proposed road corridors. The difficulty of using expert knowledge for susceptibility assessment of natural hazards, i.e. flooding, landslide and debris flow, for early transport infrastructure planning was presented in the third study (Paper III). In this study the expert knowledge was used in a multi-criteria analysis where the analytic hierarchy process (AHP) was chosen as a decision rule. This decision rule was compared to the decision rule weighted linear combination (WLC) using two different schemes of weighting. In all the mentioned studies the importance of soil thickness information was highlighted. Therefore, the fourth and final study (Paper IV) presented a new methodology for modelling the soil thickness in areas where data is sparse. A simplified regolith model (SRM) was developed in order to estimate the regolith thickness, i.e. soil thickness, for previously glaciate terrain with a high frequency of rock outcrops. SRM was based on a digital elevation model (DEM) and an optimized search algorithm. The methods developed in order to couple geological information with other areas of interest is a tentative step towards an earlier geo-environmental planning process. However, the methods need to be tested in other areas with different geological conditions. The combination of geological information in GIS with MCA enabled the integration of knowledge for decision making; it also allowed influencing the importance between various aspects of geological information as well as the importance between geological information and other fields of interest, such as ecology, through the selected weighting schemes. The results showed that synergies exist between ecology and geology, where important geological considerations could also have positive effects on ecological consideration. Soil thickness was very important for GHG emission and energy whereas stratigraphical knowledge had a minor influence. When using expert knowledge the consistency in the expert judgements also needs to be considered. It was shown that experts tended to be inconsistent in their judgements, and that some consistency could be reached if the judgements were aggregated instead of used separately. The results also showed that the developed SRM had relatively accurate results for data sparse areas, and that this model could be used in several projects where the knowledge of soil thickness is important but lacking. It was concluded that geological information should be considered. By using GIS and MCA it is possible to evaluate different aspects of geological information in order to improve decision making.

  • 190.
    Karlsson, Caroline
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Ali, Imran
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Earon, Robert
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Olofsson, Bo
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Mörtberg, Ulla
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Comparison of methods for predicting regolith thickness in previously glaciated terrain, Stockholm, Sweden2014In: Geoderma, ISSN 0016-7061, E-ISSN 1872-6259, Vol. 226, p. 116-129Article in journal (Refereed)
    Abstract [en]

    Knowledge about regolith thickness is important in several civil and environmental engineering fields. However, subsurface characteristics such as regolith thickness are difficult to determine through surface investigations and maps at regional scales. This paper presents four methods for estimating regolith thickness in a GIS environment for previously glaciated terrain with high frequency of rock outcrops: linear regression (LR) using topographical covariates; inverse distance weighting (IOW) interpolation of regolith thickness point data from well drillings: a trigonometrical approach (TA) developed for this study which uses outcrop slopes and distance between outcrops; and a simplified regolith model (SRM). The SRM is a model modified from TA which estimates the regolith thickness based on outcrops, slopes and the distance to outcrops in eight directions. The methods were compared for three study areas (Tyreso, Vallentuna and Osteraker) in Stockholm County, Sweden. Based on the results in this paper, LR proved to be the most accurate method for regolith thickness estimation, measured through root mean square error values. Whereas IDW was the most accurate method in terms of error within 2 m, which would make it a suitable model if and when large datasets of regolith point data are available. When drilling data is scarce then both the TA and SRM methods can be used for regolith estimations. However, the SRM proved to be a more accurate regolith thickness model compared to TA. SRM shows promising results and could be used at a preliminary stage in engineering projects where little or no data is available prior to detailed field investigations in previously glaciated terrain.

  • 191.
    Karlsson, Caroline
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Jamali, Imran
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Earon, Roberg
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Olofsson, Bo
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Mörtberg, Ulla
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Simplified Regolith Model (SRM): A GIS approach to estimate regolith thickness using outcrop slopes and distance to outcrops2015In: Geophysical Research Abstracts Vol. 17, EGU2015-10232, 2015, EGU General Assembly, 2015Conference paper (Refereed)
  • 192.
    Karlsson, Caroline
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Kalantari, Zahra
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Mörtberg, Ulla
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Olofsson, Bo
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Lyon, Steve
    Stockholms Universitet.
    The impact of expert knowledge on natural hazard susceptibility assessment using spatial multi-criteria analysis2016Conference paper (Refereed)
  • 193.
    Karlsson, Caroline
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Kalantari, Zahra
    Mörtberg, Ulla
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Olofsson, Bo
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Lyon, Steve W
    Natural hazard susceptibility assessment for road planning using spatial multi-criteria analysisManuscript (preprint) (Other academic)
    Abstract [en]

    Inadequate infrastructural networks can be detrimental to a society if transport between locations becomes hindered or delayed, especially due to natural hazards which are more difficult to control. Thus determining natural hazard susceptible areas and incorporating them in the initial planning process, may reduce infrastructural damages in the long run. The objective of this study was to evaluate the usefulness of expert judgements for assessing natural hazard susceptibility through a spatial multi-criteria analysis (SMCA) approach using hydrological, geological and land use factors. To utilize SMCA for decision support, an analytic hierarchy process (AHP) was adopted where expert judgements were evaluated individually and in an aggregated manner. The estimates of susceptible areas were then compared with the methods Weighted linear combination (WLC) using equal weights and Factor interaction method (FIM). Results showed that inundation received the highest percentage of susceptibility. Using expert judgement showed to perform almost same as Equal weighting where the difference (i.e. average) in susceptibility between the two for inundation was around 4%. Results also showed that downscaling could negatively affect the susceptibility assessment and be highly misleading. Susceptibility assessment through SMCA is useful for decision support in early road planning despite its limitation to selection and use of decision rule and criteria. A natural hazard SMCA could be used to indicate areas where more investigations need to be undertaken from a natural hazard point of view, and to identify areas thought to have higher susceptibility along existing roads where mitigation measures could be targeted after in-situ investigations.

  • 194.
    Karlsson, Caroline
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Kalantari, Zahra
    Mörtberg, Ulla
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Sustainability Assessment and Management.
    Olofsson, Bo
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Lyon, Steve W.
    Natural hazard susceptibility assessment for road planning using spatial multi-criteria analysis2017In: Environmental Management, ISSN 0364-152X, E-ISSN 1432-1009, Vol. 60, no 5, p. 823-851Article in journal (Refereed)
    Abstract [en]

    Inadequate infrastructural networks can be detrimental to society if transport between locations becomes hindered or delayed, especially due to natural hazards which are difficult to control. Thus determining natural hazard susceptible areas and incorporating them in the initial planning process, may reduce infrastructural damages in the long run. The objective of this study was to evaluate the usefulness of expert judgements for assessing natural hazard susceptibility through a spatial multi-criteria analysis (SMCA) approach using hydrological, geological and land use factors. To utilize SMCA for decision support, an analytic hierarchy process (AHP) was adopted where expert judgements were evaluated individually and in an aggregated manner. The estimates of susceptible areas were then compared with the methods weighted linear combination (WLC) using equal weights and factor interaction method (FIM). Results showed that inundation received the highest susceptibility. Using expert judgement showed to perform almost the same as Equal weighting where the difference in susceptibility between the two for inundation was around 4%. The results also showed that downscaling could negatively affect the susceptibility assessment and be highly misleading. Susceptibility assessment through SMCA is useful for decision support in early road planning despite its limitation to the selection and use of decision rules and criteria. A natural hazard SMCA could be used to indicate areas where more investigations need to be undertaken from a natural hazard point of view, and to identify areas thought to have higher susceptibility along existing roads where mitigation measures could be targeted after in-situ investigations.

  • 195.
    Karlsson, Caroline
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Miliutenko, Sofiia
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Björklund, Anna
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Mörtberg, Ulla
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Olofsson, Bo
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Toller, Susanna
    Life cycle assessment in road infrastructure planning using spatial geological data2017In: The International Journal of Life Cycle Assessment, ISSN 0948-3349, E-ISSN 1614-7502, Vol. 22, no 8, p. 1302-1317Article in journal (Refereed)
    Abstract [en]

    Purpose: The purpose of the study was to outline and demonstrate a new geographic information system (GIS)-based approach for utilising spatial geological data in three dimensions (i.e. length, width and depth) to improve estimates on earthworks during early stages of road infrastructure planning. Methods: This was undertaken by using three main methodological steps: mass balance calculation, life cycle inventory analysis and spatial mapping of greenhouse gas (GHG) emissions and energy use. The mass balance calculation was undertaken in a GIS environment using two assumptions of geological stratigraphy for two proposed alternative road corridors in Sweden. The estimated volumes of excavated soil, blasted rock and filling material were later multiplied with the GHG emission and energy use factors for these processes, to create spatial data and maps in order to show potential impacts of the studied road corridors. The proposed GIS-based approach was evaluated by comparing with actual values received after one alternative was constructed. Results and discussion: The results showed that the estimate of filling material was the most accurate (about 9 % deviation from actual values), while the estimate for excavated soil and blasted rock resulted in about 38 and 80 % deviation, respectively, from the actual values. It was also found that the total volume of excavated and ripped soils did not change when accounting for stratigraphy. Conclusions: The conclusion of this study was that more information regarding embankment height and actual soil thickness would further improve the model, but the proposed GIS-based approach shows promising results for usage in LCA at an early stage of road infrastructure planning. Thus, by providing better data quality, GIS in combination with LCA can enable planning for a more sustainable transport infrastructure.

  • 196.
    Karlsson, Caroline
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Miliutenko, Sofiia
    KTH.
    Björklund, Anna
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Mörtberg, Ulla
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Olofsson, Bo
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Toller, Susanna
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Life cycle assessment in road infrastructure planning using spatial geological dataManuscript (preprint) (Other academic)
  • 197.
    Karlsson, Caroline
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Miliutenko, Sofiia
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Björklund, Anna
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Mörtberg, Ulla
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Olofsson, Bo
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Toller, Susanna
    Swedish Transport Agency.
    Towards a better planning process: Can geological data be useful?2015Conference paper (Other academic)
  • 198.
    Kasunzu, Emigidius
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Assessment of Surface and Ground-water Resource Using SWAT model. A Case of Sigi River Catchments, Tanga Tanzania.2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Sigi River is a very important fresh water resource in resident of Tanga region in Tanzania. Sigi River basin is one of the basins within Pangani main catchments contributing most of the recharge water into a man made reservoir named Mabayani Dam.

    The SWAT model was applied to the Sigi Basin for modelling of the hydrological water components. The objective of this study is to evaluate the water balance of Mabayani reser-voir (dam) over the range of different years and to asses and evaluate the hydrological com-ponents of the catchments in relation to existing land use and stream flow prediction. The input data for this research were DEM, land use map, soil data, daily precipitation, daily min-imum and maximum temperature, dam management data, daily river discharge and dam wa-ter abstraction.

    The sensitivity analysis of the model indicates that some hydrological controlling parameter can be identified without observed data. The sensitivity analysis indicates the flow is more sensitive to hydrologic response unit. The Parasol calibration of the monthly discharge gave moderately satisfactory Nash Sutcliffe Coefficient of Efficiency of 75%.

    The hydrological modelling resulting to a mean total annual water yield of 850 mm of which the mean annual surface runoff was 500 mm and base flow was 310 mm. The simulation in-dicates the surface runoff is important hydrological component compared to base flow

    The outcome of this study can assist the decision makers, water use planners, and stakehold-ers in the best ways to manage the existing surface and groundwater resources within the Sigi catchments.

  • 199.
    Ketema, Ghebriel Kidane
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Optimization of Physical Properties for Ditches–Case Study: Kankberg, Maurliden and Renström-Petiknäs.2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    It is important for practical and legal reasons that water and sediments in disturbed areas around the mining operation should be controlled. The construction of a well-designed drainage system that controls erosion and thus restores the proper hydraulic function of the surface is one of the most important post-disturbance features which should be done as part of the mining activities. However, even with the best planning and design, unless proper construction practices are adapted; both the disturbed and reclaimed areas are very much likely to be susceptible to erosion, sedimentation and stability problems. In order to tackle the problem, guidelines on how to design and construct the drainage system should be well prepared. The main objective of this study was to prepare guidelines for the proper design, construction and monitoring of the water drainage management system in the study areas (Kankberg, Maurliden and Renström-Petiknäs). This report has analysed the results from the outcome of HEC-RAS software for the case study of the new ditch around the Maurliden mine site and integrated with different guidelines. Based on the results of the HEC-RAS, the most common problems in the drainage system have been identified. Moreover the thesis project identified important physical parameters such as cross-sections and slopes of the representative ditch which affect the function of the ditch in the study areas. Hydraulic parameters such as velocity which is very important for designing the type of lining and also Froude number which is very important in identifying the type of flow whether it is super-critical, critical or sub-critical were identified. The latter helps to select the type of guideline to be used between steep slope and mild slope.

  • 200.
    Kholoma, Ezekiel
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Fortification of soil-based wastewater treatment systems with versatile ubiquitous reactive media for enhanced removal of phosphorus and other pollutants2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Concerns about potential risks posed by discharge from small-scale wastewater treatment (SWT) systems to receiving water bodies have prompted robust enforcement of national discharge quality standards in rural areas of most developed countries. Consequently, communities in such places are in need of effective technologies with which to achieve compliance. Currently, reactive filter (RF) media are increasingly preferred over advanced alternatives, due mainly to their simplicity, affordability and proven potential. However, many of the field-tested filters are commercial products which are costly and scarce but also only capable of removing few contaminants they are engineered to target hence often requiring to be coupled with other treatment units to achieve full treatment. In the preliminary findings of this study, biochar (BC) was identified and thus suggested basing on existing literature, as a versatile ubiquitous low-cost material for treating wastewater. Its effectiveness in fortifying sand (Sa) and gas concrete (GC)-based SWT facilities was later demonstrated in long-term experiments using laboratory packed bed reactors and field constructed filter beds. The efficacy of SaBC and GCBC systems in reducing turbidity (>95%), DOC (60%; p<0.05) and PO43- (40-90%; p<0.05) was significantly higher than for their reference counterparts. Further, sorbed P was more leachable from Sa (11.2 mgkg-1) and SaBC (20.5 mgkg-1) filters but more extractable and hence plant-available in GC (65-91 mgkg-1). Therefore, the study concluded that fortification of soil-based systems with biochar filters may be a promising solution in enhancing performances of soil-based wastewater treatment systems, while P-rich RF media can act as a nutrient source for plants if recycled to agriculture.

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