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  • 301.
    Darwesh, Ali
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Rasmussen, Thorkild Maack
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Evaluation of Limestone Interval in the Drilled Surface Section of Bn-1 Oil Well2016In: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 8, no 8, p. 515-524Article in journal (Refereed)
    Abstract [en]

    The first exploration oil well in any oil block consumes in general more time and cost than the other wells in the same block. Evaluating the drilled wells serves to improve the future operations. This paper evaluates the drilled surface section through real field data for the first exploration oil well drilled in one of the oil blocks, in Kurdistan north of Iraq. The surface section of the well was drilled with the conventional method to penetrate many different geological formations with tight intervals. Drilling efficiency and the difficulties encountered are discussed and explained using various data sources. All daily drilling reports concerning a specific interval were studied. This includes weight on bit, string rotation, mud pump flow and penetration rate. Evaluation was carried out by analyzing the used controllable drilling parameters with the formations features. Penetration of the Pila Spi formation (Middle Eocene) was the most difficult formation in the drilled section. Microsoft Office 365 Pro Plus used in making graphs and Excel tables. Evaluations showed that the conventional technology used left many negative effects, like increase in None Productive Time NPT, cost and ground water pollution. Simultaneous Casing Drilling method proposed as an alternative method for the future campaign.

  • 302. Das, U.C.
    et al.
    Parasnis, Dattatray
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Resistivity and induced polarization responses of arbitarily shaped 3-D bodies in a two-layered Earth1987In: Geophysical Prospecting, ISSN 0016-8025, E-ISSN 1365-2478, Vol. 35, no 1, p. 98-109Article in journal (Refereed)
  • 303.
    Dehghannejad, A.
    et al.
    Uppsala University.
    Juhlin, C.
    Uppsala University.
    Malehmir, A.
    Uppsala University.
    Weihed, Pär
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    High-resolution reflection seismic imaging in the Kristineberg mining area, Northern Sweden2010In: 72nd European Association of Geoscientists and Engineers conference and exhibition 2010: Barcelona, 14 - 17 June 2010, Curran Associates, Inc., 2010, p. 5368-5371Conference paper (Refereed)
    Abstract [en]

    The Kristineberg mining area is located in the western part of the Skellefte Ore District, one of the most important mining districts in Europe. As a part of a 4D geologic modeling project, two new reflection seismic profiles were acquired. Although the structural geology is complex, the processed seismic data reveal a series of steeply dipping to sub-horizontal reflections, some of which reach the surface and allow correlation with surface geology. Reflection modeling was carried out to obtain the 3D orientation of the main reflections and to provide insight into the possible contribution of out-of-the-plane reflections. The new reflection seismic profiles have improved our understanding of shallow geological structures in the area and in conjunction with recently acquired potential field data, magnetotelluric data and geological observations will help to refine previous 3D geologic modeling interpretations that were aimed at larger scale structures.

  • 304.
    Dehghannejad, M.
    et al.
    Uppsala universitet.
    Juhlin, C.
    Uppsala universitet.
    Malehmir, A.
    Uppsala universitet.
    Weihed, Pär
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    High-resolution reflection seismic imaging in the Skellefte ore district: a contribution to 4D geologic modeling2009In: Geophysical Research Abstracts: Vol. 11, EGU2009-4894, 2009, 2009Conference paper (Other academic)
    Abstract [en]

    The Kristineberg VHMS (volcanic-hosted massive sulfide) mining area is located in the western part of the Skellefte Ore District, the most important metallogenic zone in northern Sweden. The area has been the subject of several geological and geophysical studies with the aim of understanding the contact relationships between the ore bearing volcanic and volcanosedimentary formations and the surrounding rocks. To establish the structural geologic framework at depth, two new reflection seismic profiles, a N-S directed high resolution one with a length of about 6.3 km and an E-W directed one perpendicular to the high-resolution profile with a length of about 13 km were acquired in 2008. Although the structural geology is complex, a preliminary stacked section of the high-resolution profile reveals a series of steeply dipping to sub-horizontal reflections in the southern and northern parts of the profile, many of which can be traced to the surface for correlation with surface geology. Several reflections appear to be consistent with reflections observed in two previously acquired profiles in the study area. The new reflection seismic results will be integrated with the previous reflection seismic results, potential field modeling, magnetotelluric data and geological observations to improve earlier geological interpretations that led to a pilot 3D geologic model of the study area.

  • 305.
    Dehghannejad, Mahdieh
    et al.
    Department of Earth Sciences, Uppsala University.
    Bauer, Tobias
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Malehmir, Alireza
    Department of Earth Sciences, Uppsala University.
    Juhlin, Christopher
    Department of Earth Sciences, Uppsala University.
    Weihed, Pär
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Crustal geometry of the central Skellefte district, northern Sweden: constraints from reflection seismic investigations2012In: Tectonophysics, ISSN 0040-1951, E-ISSN 1879-3266, Vol. 524-525, p. 87-99Article in journal (Refereed)
    Abstract [en]

    The Palaeoproterozoic Skellefte mining district in Sweden is one of the most important mining districts in Europe. As a part of a 4D geologic modeling project, three new sub-parallel reflection seismic profiles, with a total length of about 95 km, were acquired in the central part of the district. Processed seismic data reveal a series of gentle- to steeply- dipping reflections and a series of diffraction packages. The majority of reflections that extend to the surface can be correlated with geological features either observed in the field or interpreted from the aeromagnetic map. A set of south-dipping reflections represent inferred syn-extensional listric extensional faults that were inverted during subsequent crustal-shortening. Cross-cutting north-dipping reflections are correlated to late-compressional break-back faults. Flat-lying reflections in the central parts of the study area could represent lithological contacts within the Skellefte Group, or the contact between Skellefte Group rocks and their unknown basement. Flat-lying reflections occurring further north are inferred to originate from the top of the Jörn intrusive complex or an intrusive contact within it. So far unknown south- and north-dipping faults have been identified in the vicinity of the Maurliden deposit. Based on the seismic results, a preliminary 3D-model has been created in order to visualize the fault pattern and to provide a base for future 3D/4D modeling in the Skellefte district.

  • 306.
    Dehghannejad,, Mahdieh
    et al.
    Department of Earth Sciences, Uppsala University.
    Juhlin,, Christopher
    Department of Earth Sciences, Uppsala University.
    Malehmir, Alireza
    Department of Earth Sciences, Uppsala University.
    Juanatey, Maria A. Garcia
    Department of Earth Sciences, Uppsala University.
    Skyttä, Pietari
    Department of Geosciences and Geography, University of Helsinki, FI-00014 Helsinki.
    Weihed, Pär
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Bauer, Tobias
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Reflection seismic imaging in the Skellefte ore district, northern Sweden2013In: Mineral depostits for a high-tech world: Proceedings of the 12th SGA Biennial Meeting 2013, 12-15 August 2013, Uppsala, Sweden, Uppsala: Sveriges Geologiska Undersökning , 2013, Vol. 1, p. 126-129Conference paper (Refereed)
  • 307.
    Dehghannejad, Mahdieh
    et al.
    Uppsala universitet.
    Juhlin, Christopher
    Uppsala universitet.
    Malehmir, Alireza
    Uppsala universitet.
    Skyttä, Pietari
    Weihed, Pär
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Reflection seismic imaging of the upper crust in the Kristineberg mining area, northern Sweden2010In: Journal of Applied Geophysics, ISSN 0926-9851, E-ISSN 1879-1859, Vol. 71, no 4, p. 125-136Article in journal (Refereed)
    Abstract [en]

    The Kristineberg mining area is located in the western part of the Palaeoproterozoic Skellefte Ore District, one of the most important mining districts in Europe. As a part of a 3D geologic modeling project, two new reflection seismic profiles were acquired with a total length of about 20 km. One profile (HR), parallel to previous seismic profiles, was acquired using a 10 m receiver and source interval and crosses the steeply dipping structures of the Kristineberg mine. The other profile (Profile 2) runs perpendicular to all existing profiles in the area. Although the structural geology is complex, the processed seismic data reveal a series of steeply dipping to sub-horizontal reflections, some of which reach the surface and allow correlation with surface geology. Our general interpretation of the seismic images is that the Kristineberg mine and associated mineral horizon are located in the northern part of a series of steeply south dipping structures. Overall, main structures plunge to the west at about 30° - 40°. Cross-dip analysis and reflection modeling were carried out to obtain the 3D orientation of the main reflections and to provide insight into the possible contribution of out-of-the-plane reflections. This helped, for example, to obtain the 3D geometry of a deep reflection that was previously interpreted as structural basement to volcanic rocks. The new reflection seismic profiles have improved our understanding of shallow geological structures in the area and in conjunction with recently acquired potential field data, magnetotelluric data and geological observations will help to refine previous 3D geologic modeling interpretations that were aimed at larger scale structures.

  • 308.
    Dehghannejad, Mahdieh
    et al.
    Uppsala universitet.
    Malehmir, Alireza
    Uppsala universitet.
    Juhlin, Christopher
    Uppsala universitet.
    Skyttä, Pietari
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    3D constraints and finite-difference modeling of massive sulfide deposits: the Kristineberg seismic lines revisited, northern Sweden2012In: Geophysics, ISSN 0016-8033, E-ISSN 1942-2156, Vol. 77, no 5, p. WC69-WC79Article in journal (Refereed)
    Abstract [en]

    The Kristineberg mining area in the western part of the Skellefte ore district is the largest base metal producer in northern Sweden and currently the subject of extensive geophysical and geologic studies aimed at constructing 3D geologic models. Seismic reflection data form the backbone of the geologic modeling in the study area. A geologic cross section close to the Kristineberg mine was used to generate synthetic seismic data using acoustic and elastic finite-difference algorithms to provide further insight about the nature of reflections and processing challenges when attempting to image the steeply dipping structures within the study area. Synthetic data suggest processing artifacts manifested themselves in the final 2D images as steeply dipping events that could be confused with reflections. Fewer artifacts are observed when the data are processed using prestack time migration. Prestack time migration also was performed on high-resolution seismic data recently collected near the Kristineberg mine and helped to image a high-amplitude, gently dipping reflection occurring stratigraphically above the extension of the deepest Kristineberg deposit. Swath 3D processing was applied to two crossing seismic lines, west of the Kristineberg mine, to provide information on the 3D geometry of an apparently flat-lying reflection observed in both of the profiles. The processing indicated that the reflection dips about 30° to the southwest and is generated at the contact between metasedimentary and metavolcanic rocks, the upper part of the latter unit being the most typical stratigraphic level for the massive sulfide deposits in the Skellefte district.

  • 309. Denisova, Nikola
    et al.
    Allan, Åsa
    Martinsson, Olof
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Sulfide distribution and its relation to different types of skarn alteration at the Tapuli deposit, northern Sweden2013In: Mineral deposit research for a high-tech world: proceedings / [ed] Erik Jonsson, Uppsala: Sveriges Geologiska Undersökning , 2013, p. 1539-1542Conference paper (Refereed)
    Abstract [en]

    The Tapuli deposit is a skarn iron ore located in the Pajala municipality in Northern Sweden. It is situated at the margin of the Karelian craton, at the stratigraphic contact between Karelian and Svecofennian rocks. The ore forms stratabound lenses concordant with the metasedinnentary sequences and dips 45 - 60 degrees towards NW. Footwall rocks are dolomitic marbles, phyllites and graphitic phyllites; the hanging wall comprises phyllites and quartzites. Mafic dykes and sills crosscut the stratigraphic succession. Magnetite is the only ore mineral. The skarn minerals are serpentine, diopside, tremolite and actinolite. The skarn altered rocks show a zonation with serpentine skarn closest to or as part of the ore, thereafter, tremolite-diopside skarn and, finally, actinolite skarn closest to the phyllites and quartzites in the hanging wall. Sulfides occur in minor amounts, but their content generally increases with proximity to the footwall rocks. The dolomitic marble was the precursor of the serpentine and tremolite-diopside skarn. Immobile element data suggests that mafic dykes and sills were the precursors of the actinolite skarn. Possible controls of the sulfide distribution are the presence of sulfide-bearing source rocks (dolomitic marble, graphitic phyllite) and rennobilization of sulfides during the intrusion of mafic dykes.

  • 310. Diaz, Luis F.
    et al.
    Eggerth, Linda L.Lagerkvist, AndersLuleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Proceedings of the 3rd Swedish Landfill Research Symposium: Luleå University of Technology, 6th-8th October 19981999Collection (editor) (Other academic)
  • 311.
    Diener, Silvia
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Ageing behaviour of steel slags in landfill liners2009Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Steel slags are by-products of the steelmaking process. To avoid unnecessary disposal, e.g. into landfill, their chemical and physical properties should be exploited to support alternative uses. Steel slags can be recycled within the steel plant or used as construction material in roads, hydraulic engineering and different types of barriers, including landfill covers. A landfill cover consists of several layers, including a liner with low water and gas permeability in order to reduce methane and leachate emissions. Several studies have demonstrated that steel slags have good potential to fulfil such an application. However, there are questions regarding the stability of the slag minerals over long periods of time. A landfill cover must function well for many decades and centuries. In order to predict the long-term stability of steel slags as a landfill liner, laboratory experiments have been performed to study the effects of accelerated ageing of steel slag under controlled conditions. The factors investigated in the storage atmosphere were carbon dioxide content, relative humidity and temperature. The influence of leachate contact and ageing time were also assessed.This thesis reports the study of electric arc furnace slags and ladle slag from the production of high-alloyed tool steel after accelerated ageing for periods of three months and ten months. Mineralogy and leaching were studied using two different leaching tests, thermal analysis, acid-neutralization capacity assays and X-ray diffraction. For the ageing periods considered, the exposure of the slags to an atmosphere enriched with carbon dioxide had the greatest impact on leaching. In general, calcium, aluminium, sulphur and sodium leached from the slag matrix to the greatest extent while other metals such as chromium, nickel, lead and zinc were found at very low levels in the leachate. The leaching of calcium and aluminium reduced with increasing carbon dioxide level. Thermal analysis revealed the decomposition of carbonates. Weight and enthalpy changes were evaluated between 100 and 1000 °C. The buffer capacity of the steel slags, represented by the acid neutralization capacity (ANC 4.5) was not reduced after 10 months of ageing. However, the division of the titration into two steps revealed a shift of buffering zones for more highly aged samples, probably due to the formation of carbonates. The mineralogy of the investigated steel slags was complex with a large variety of mineral phases, principally calcium silicates, monticellite, periclase and a spinel phase. Other possible phases were gehlenite, merwinite, akermanite and iron. The existence of different solid solution is likely among the slag phases and can cause shifting of peaks in the X-ray diffractogram. Also, calcite was identified. Short-term carbonation has not shown significant impact on mineralogy despite of calcite formation. The results of the study contribute to a better understanding of the chemical and mineral stability of electric arc furnace slag and ladle slag in the environment of a landfill liner. The consequences of slag ageing include reduced leaching rates for certain elements. To predict the long-term behaviour of aged slag, the results of this study should be combined with data from two other sources - an ongoing ageing experiment that includes mechanical tests and a full scale field test at the Hagfors landfill. Additional analytical methods that can better characterise the mineralogy, for example scanning electron microscopy (SEM) and energydispersive X-ray spectroscopy (EDX), should also be applied to better quantify the mineralogical phases and to determine which trace elements are most abundant in specific minerals.

  • 312. Diener, Silvia
    et al.
    Andreas, Lale
    Brännvall, Evelina
    Lagerkvist, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Evaluation and discussion of steel slag mineralogy after ageing under laboratory and field conditions2010In: The 6th Intercontinental Landfill research Symposium, 2010, p. 107-109Conference paper (Other academic)
  • 313.
    Diener, Silvia
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Andreas, Lale
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Herrmann, Inga
    Ecke, Holger
    Lagerkvist, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Accelerated carbonation of ashes and steel slags in a landfill cover construction2008In: Proceedings of Second International Conference on Accelerated Carbonation for Environmental and Materials Engineering / [ed] Renato Baciocchi; Giulia Costa; Alessandra Polettini; Raffaella Pomi, University of Rome "La Sapienza" , 2008, p. 389-400Conference paper (Refereed)
    Abstract [en]

    Fly ash from biofuel incineration and slags from steel production were used in two full scale applications of cover constructions on municipal solid waste (MSW) landfills. The long-term stability of the cover materials is studied in a designed laboratory experiment. The impact of six environmental factors on accelerated carbonation is investigated over a period of three years. Leaching behaviour, acid neutralization capacity, mineral composition (XRD) and thermo gravimetrical behaviour (TG) are tested after different periods of ageing under different conditions. By now samples were taken after three and ten months of ageing. Multivariate data analysis was used for data evaluation. The results indicate the factors material, ageing time and carbon dioxide content of the atmosphere to be most relevant.

  • 314. Diener, Silvia
    et al.
    Andreas, Lale
    Herrmann, Inga
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Ecke, Holger
    Lagerkvist, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Accelerated carbonation of steel slags in a landfill cover construction2010In: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 30, no 1, p. 132-139Article in journal (Refereed)
    Abstract [en]

    Steel slags from high-alloyed tool steel production were used in a full scale cover construction of a municipal solid waste (MSW) landfill. In order to study the long-term stability of the steel slags within the final cover, a laboratory experiment was performed. The effect on the ageing process, due to i.e. carbonation, exerted by five different factors resembling both the material characteristics and the environmental conditions is investigated. Leaching behaviour, acid neutralization capacity and mineralogy (evaluated by means of X-ray diffraction, XRD, and thermogravimetry/differential thermal analysis, TG/DTA) are tested after different periods of ageing under different conditions.Samples aged for 3 and 10 months were evaluated in this paper. Multivariate data analysis was used for data evaluation. The results indicate that among the investigated factors, ageing time and carbon dioxide content of the atmosphere were able to exert the most relevant effect. However, further investigations are required in order to clarify the role of the temperature.

  • 315.
    Diener, Silvia
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Andreas, Lale
    Herrmann, Inga
    Lagerkvist, Anders
    Mineral transformations in steel slag used as landfill cover liner material2007In: SARDINIA 2007: Eleventh International Waste Management and Landfill Symposium ; [1 - 5 October 2007, S. Margherita di Pula, Cagliari, Sardinia, Italy] / [ed] Raffaello Cossu, Cagliari: CISA, Environmental Sanitary Engineering Centre , 2007, Vol. 1Conference paper (Refereed)
    Abstract [en]

    In Europe, 15.2 million tonnes of steel slags have been generated in 2004 (Euroslag, 2006) out if which almost 6 million tonnes came from electric arc furnace (EAF) steelmaking and secondary metallurgical processes. In the presented project from Luleå University of Technology, two types of EAF slag and one slag originating from secondary metallurgical processes named ladle slag are investigated. The chemical and physical properties of these slags have been studied in detail (Herrmann, 2006; Andreas et al., 2005). For utilising steel slags in the liner of a landfill cover the long-term stability of the minerals is of great importance. Therefore, the ageing of steel slag minerals is evaluated with the help of a laboratory experiment. Particularly, the research questions, the experimental set-up and the methodology are presented. The present paper is part of a research project of the Division of Waste Science and Technology at Luleå University of Technology, Sweden in cooperation with Uddeholm Tooling AB, Hagfors municipality and MiMeR (Mineral and Metal Recycling Research Centre). It is investigated if steel slags are stable as a landfill cover liner material. The long-term stability is evaluated by determining the factors influencing the mineralogy of the slags and possible mineral transformations through ageing under the environmental conditions in a liner. The experiment includes two similar types of EAF slag and one ladle slag. Each steel slag sample is made by mixing 50% EAF slag and 50% ladle slag, addition of water and compaction. The specimens are stored in boxes under different atmospheric conditions. A reduced multivariate design has been chosen to determine the impact of different factors on the slag mineralogy. The factors that are varied in the experiment are relative humidity, carbon dioxide and temperature of the atmosphere surrounding the slag material as well as ageing time and the quality of the water used for sample making (see table 1). Table 1. Factorial design for ageing experiment of steel slagsLowMiddleHighRelative humidity30% -100%Carbon dioxide content0.036 (air)20 % * 100 %Temperature5 °C30 °C60 °CTime 1 month6 months1 yearWater quality destilled water -LeachateThe ageing of minerals is expected to initiate mineral transformations in steel slags. Primary phases will alter into secondary mineral phases. Changes in mineralogy can influence the stability of the liner. To evaluate mineralogy and properties of the aged steel slag, different analyses will be performed after the storage time of the specimens. X-ray diffraction and scanning electron microscopy as well as shear strength, acid neutralisation capacity and cation exchange capacity will be included. A possible mineral transformation for an alkaline material as steel slags can be the reaction of calcium ions from calcium silicates with the carbon dioxide resulting in the precipitation of calcium carbonate. Through this carbonation reaction, the transport of carbon dioxide into the bulk of the specimen could be hindered by the reaction products. Therefore, surface morphology can influence mineral transformations. First results and evaluations will be presented at the conference. REFERENCES Andreas L., Herrmann I., Lidstrom-Larsson M. & Lagerkvist A. (2005) Physical properties of steel slag to be reused in a landfill cover, Sardinia 2005, Tenth International Waste Management and Landfill Symposium, S. Margherita di Pula, Cagliari, Italy; 3 - 7 October 2005Euroslag (2006) Legal status of Slags. Position Paper. January 2006. The European Slag Association - EUROSLAG. Duisburg, Germany.Herrmann I. (2006). Use of Secondary Construction Material in Landfill Cover Liners. Licentiate Thesis. Luleå University of Technology, Sweden.

  • 316. Diener, Silvia
    et al.
    Andreas, Lale
    Herrmann, Inga
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Lagerkvist, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Results from a field study using steel industry slags in a landfill cover construction2008Conference paper (Other academic)
  • 317.
    Diener, Silvia
    et al.
    Dresden University of Technology.
    Andreas, Lale
    Herrmann, Inga
    Lagerkvist, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Lidström-Larsson, Margareta
    Mineral phases in steel industry slags used in a landfill cover constuction2006In: Abstract proceedings of the 4th Intercontinental Landfill Research Symposium, , [June 14th to 16th 2006, Gällivare, Sweden] / [ed] Anders Lagerkvist, Luleå: Luleå tekniska universitet, 2006, p. 73-74Conference paper (Other academic)
  • 318.
    Diener, Silvia
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Brännvall, Evelina
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Andreas, Lale
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Leaching properties of steel slags after ageing under laboratory and field conditions2010In: Third International Conference on Accelerated Carbonation for Environmental and Materials Engineering: ACEME10 : November 29 - December 1, 2010, Åbo Akademi University, Åbo/Turku, Finland : proceedings / [ed] Ron Zevenhoven., Åbo: Åbo Akademi University Press, 2010Conference paper (Refereed)
  • 319.
    Dold, Bernhard
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Acid rock drainage prediction: A critical review2016In: Journal of Geochemical Exploration, ISSN 0375-6742, E-ISSN 1879-1689, Vol. 172, p. 120-132Article in journal (Refereed)
    Abstract [en]

    Acid rock drainage (ARD) prediction is a very important issue in order to predict and prevent environmental pollution associated with mining activities. Nowadays, simple tests are widely applied and established in the mining and consulting business for ARD prediction. These tests have many known errors and problems, as that they do not account for the complexity of the mineral assemblage of an ore deposit, and therefore are not able to predict the geochemical behavior accurately. This critical review has the aim of first, highlighting the geochemical processes associated to the problems of ARD prediction. Secondly, the errors and limitations of the standard static and kinetic tests are highlighted. The currently applied calculation factor of 31.25 for sulfide acid potential calculation overestimates the carbonate neutralization potential by 100% in its geochemical assumptions. Thus, the calculation factor 62.5, based on the effective carbonate speciation at neutral pH, is recommended. Additionally, standard ABA procedure ignore the acid potential of Fe(III) hydroxides and/or sulfates and do not distinguish between different carbonate minerals. This can be critical, as for example siderite can be a net acid producing carbonate. Therefore, it is crucial to count on accurate quantitative mineral data in order to be able to accurately predict ARD formation and potential liberation of hazardous trace elements to the environment.

    In many modern mining operations, quantitative mineral data is nowadays produced in order to enhance the recovery of the extraction process by the incorporation of geometallurgical information (e.g. quantitative mineralogy, mineral liberation, textural information, grain size distribution). Thus, the use of this very same existing data for ARD prediction can increase importantly the precision of ARD prediction, often without additional costs and testing. The only requirement is the interdisciplinary collaboration between the different divisions and data exchange in a modern mining operation.

  • 320.
    Dold, Bernhard
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Pooler, Robert
    SGS Minerals Chile, Geometallurgy Area, Puerto Madero 130, Pudahuel, Santiago.
    Optimization and quality control of automated quantitative mineralogy analysis for acid rock drainage prediction2017In: Minerals, ISSN 2075-163X, E-ISSN 2075-163X, Vol. 7, no 1, article id 12Article in journal (Refereed)
    Abstract [en]

    Low ore-grade waste samples from the Codelco Andina mine that were analyzed in an environmental and mineralogical test program for acid rock drainage prediction, revealed inconsistencies between the quantitative mineralogical data (QEMSCAN®) and the results of geochemical characterizations by atomic absorption spectroscopy (AAS), LECO® furnace, and sequential extractions). For the QEMSCAN® results, biases were observed in the proportions of pyrite and calcium sulfate minerals detected. An analysis of the results indicated that the problems observed were likely associated with polished section preparation. Therefore, six different sample preparation protocols were tested and evaluated using three samples from the previous study. One of the methods, which involved particle size reduction and transverse section preparation, was identified as having the greatest potential for correcting the errors observed in the mineralogical analyses. Further, the biases in the quantities of calcium sulfate minerals detected were reduced through the use of ethylene glycol as a polishing lubricant. It is recommended that the sample preparation methodology described in this study be used in order to accurately quantify percentages of pyrite and calcium sulfate minerals in environmental mineralogical studies which use automated mineralogical analysis

  • 321. Domeij, Lisa
    et al.
    Lagerkvist, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Meijer, J-E
    Vukicevic, S.
    How to describe and compare the effects of MSW source sorting systems2005In: SARDINIA 2005: Tenth International Waste Management and Landfill Symposium ; S. Margerita di Pula, Sardinia, Italy, 3 - 7 October 2005 / [ed] Raffaello Cossu, Cagliari: CISA, Environmental Sanitary Engineering Centre , 2005Conference paper (Refereed)
  • 322.
    Domeij, Lisa
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Vukicevic, Sanita
    NSR.
    Lagerkvist, Anders
    Meijer, Jan-Erik
    NSR.
    Utvärdering av hushållens källsortering i sex kommuner: Resultat från plockanalyser vid olika insamlings- och sorteringssystem för hushållsavfall2004Report (Other academic)
  • 323.
    Donadini, Fabio
    et al.
    Scripps Institution of Oceanography, La Jolla, United States of America.
    Elming, Sten-åke
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Tauxe, Lisa
    Scripps Institution of Oceanography, La Jolla, United States of America.
    Paleointensity results from the 1.7 GA old hoting Gabbro, Sweden2009Conference paper (Other academic)
    Abstract [en]

    Complete text of publication follows. The Hoting Gabbro is located in the western part of the Central Svecofennian Subprovince, and dates about 1.786+-0.010 Ga. In the Hoting area, dykes intruded at around 1.6 Ga, and partly remagnetized the gabbros. Previous paleomagnetic and geochemical studies indicated that the stable characteristic remanent magnetization was acquired at about 1.7 Ga, when the slow cooling of the gabbro is taken into account. Preliminary palaeointensity studies from gabbros in the Hoting area suggested a very low field of about 5.8+-1.9 muT. Unfortunately, at that stage, only two sites out of nine yielded results. During 2008, we sampled seven sites from the Hoting area in order to perform new palaeointensity experiments. At Scripps, we applied the IZZI method on 60 specimens, and 39 yielded reliable results varying between 3 and 20 muT, and confirm the previous low results. Low field values have been associated with oxyexolution processes that might bias the palaeointensity result towards low values, and so we are currently investigating the mineralogy of the samples with SEM analyses. We will present the details of the palaeointensity and mineralogical results, and infer the evolution of the geomagnetic field during Precambrian.

  • 324.
    Donadini, Fabio
    et al.
    Institut für Geophysik, ETH Zürich.
    Elming, Sten-Åke
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Tauxe, Lisa
    Scripps Institution of Oceanography, University of California, San Diego.
    Hålenius, Ulf
    Swedish Museum of Natural History, Department of Mineralogy.
    Paleointensity determination on a 1.786 Ga old gabbro from Hoting, Central Sweden2011In: Earth and Planetary Science Letters, ISSN 0012-821X, E-ISSN 1385-013X, Vol. 309, no 3-4, p. 234-248Article in journal (Refereed)
    Abstract [en]

    Paleointensities from Precambrian rocks are rare and might be biased by remagnetization processes. Here we present new analyses of samples from a 1.786 Ga gabbro near Hoting, Central Sweden. Rock magnetic and mineralogical analyses indicate that one of the sites (site 5) may be pristine, whereas the others exhibit evidence of alteration. Characteristic remanent magnetization was determined using principal component analysis for each sample and was compared with results obtained in a previous study of Elming et al. (2009). Intensity measurements from site 5 show higher values compared to those of the other sites, suggesting that alteration processes may lead to underestimation of the field intensity. After cooling rate and anisotropy correction, the field moment at 1.786 Ga was estimated to be 25.6 ± 3.3 ZAm2 and 15.2 ± 6.1 ZAm2 from site 5 only and from all sites respectively. We consider the result from site 5 to be more accurate owing to the lack of evidence for alteration; our estimates agree well with the Proterozoic VDM values suggested by Biggin et al. (2009).

  • 325.
    Drielsma, Johannes A
    et al.
    European Association of Mining Industries, Metal Ores and Industrial Minerals, Avenue de Broqueville/Broquevillelaan 12, 1150 Brussels.
    Russell-Vaccari, Andrea J.
    Align Consulting, 1134 Cross Creek Ct., Sheridan, WY.
    Drnek, Thomas
    RHI AG, Magnesitstrasse 30, 8614 Breitenau.
    Brady, Tom
    Newmont Mining, 6363 South Fiddler’s Green Circle Suite 800, Greenwich Village, CO 80111.
    Weihed, Pär
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Mistry, Mark
    The Nickel Institute, Avenue des Arts/Kunstlaan, 13, 1210 Brussels.
    Simbor, Laia Perez
    European Copper Institute, Avenue de Tervueren/Tervurenlaan 168 b-10, 1150 Brussels.
    Erratum to: Mineral resources in life cycle impact assessment: defining the path forward2016In: The International Journal of Life Cycle Assessment, ISSN 0948-3349, E-ISSN 1614-7502, Vol. 21, no 1, p. 133-Article in journal (Refereed)
  • 326.
    Drielsma, Johannes A
    et al.
    European Association of Mining Industries, Metal Ores and Industrial Minerals, Avenue de Broqueville/Broquevillelaan 12, 1150 Brussels.
    Russell-Vaccari, Andrea J.
    Align Consulting, 1134 Cross Creek Ct., Sheridan, WY.
    Drnek, Thomas
    RHI AG, Magnesitstrasse 30, 8614 Breitenau.
    Brady, Tom
    Newmont Mining, 6363 South Fiddler’s Green Circle Suite 800, Greenwich Village, CO 80111.
    Weihed, Pär
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Mistry, Mark
    The Nickel Institute, Avenue des Arts/Kunstlaan, 13, 1210 Brussels.
    Simbor, Laia Perez
    European Copper Institute, Avenue de Tervueren/Tervurenlaan 168 b-10, 1150 Brussels.
    Mineral resources in life cycle impact assessment: defining the path forward2016In: The International Journal of Life Cycle Assessment, ISSN 0948-3349, E-ISSN 1614-7502, Vol. 21, no 1, p. 85-105Article in journal (Refereed)
    Abstract [en]

    Purpose: Despite 20 years of research, there remains no robust, globally agreed upon method—or even problem statement—for assessing mineral resource inputs in life cycle impact assessment (LCIA). As a result, inclusion of commonly used methods such as abiotic depletion potential (ADP) in life cycle assessment (LCA)-related evaluation schemes could lead to incorrect decisions being made in many applications. In this paper, we explore in detail how to improve the way that life cycle thinking is applied to the acquisition of mineral resources and their metal counterparts. Methods: This paper evaluates the current body of work in LCIA with regard to “depletion potential” of mineral resources. Viewpoints from which models are developed are described and analyzed. The assumptions, data sources, and calculations that underlie currently used methods are examined. A generic metal-containing product is analyzed to demonstrate the vulnerability of results to the denominator utilized in calculating ADP. The adherence to the concept of the area of protection (AOP) is evaluated for current models. The use of ore grades, prices, and economic availability in LCIA is reviewed. Results and discussion: Results demonstrate that any work on resource depletion in a life cycle context needs to have a very clear objective or LCIA will not accurately characterize mineral resource use from any perspective and decision-making will continue to suffer. New, harmonized terminology is proposed so that LCA practitioners can build better mutual understanding with the mineral industry and recommendations regarding more promising tools for use in life cycle sustainability assessment (LCSA) are given. Conclusions: The economic issue of resource availability should be evaluated in parallel with traditional LCA, not within. LCIA developers should look to economists, the market, and society in general, for broader assessments that consider shorter-time horizons than the traditional LCIA methods. To do so, the concept of the AOP in LCA needs to be redefined for LCSA to ensure that models estimate what is intended. Finally, recommendations regarding mineral resource assessment are provided to ensure that future research has a sound basis and practitioners can incorporate the appropriate tools in their work

  • 327.
    Dudley, Bernard J.
    et al.
    Centre for Ecology and Hydrology, Bush Estate, Penicuik.
    Dunbar, Michael
    Centre for Ecology and Hydrology, Wallingford, Oxon.
    Penning, Ellis
    Deltares, Delft.
    Kolada, Agnieszka
    Institute of Environmental Protection - National Research Institute, Warsaw.
    Hellsten, Seppo K.
    Finnish Environment Institute (SYKE), University of Oulu.
    Oggioni, Alessandro
    Institute for Electromagnetic Sensing of the Environment CNR - IREA, Via Bassini.
    Bertin, Vincent
    Irstea, UR REBX, 50 Avenue de Verdun.
    Ecke, Frauke
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Søndergaard, Martin
    Institute of Bioscience, Aarhus University.
    Measurements of uncertainty in macrophyte metrics used to assess European lake water quality2013In: Hydrobiologia, ISSN 0018-8158, E-ISSN 1573-5117, Vol. 704, no 1, p. 179-191Article in journal (Refereed)
    Abstract [en]

    Uncertainty is an important factor in ecological assessment, and has important implications for the ecological classification and management of lakes. However, our knowledge of the effects of uncertainty in the assessment of different ecological indicators is limited. Here, we used data from a standardized campaign of aquatic plant surveys, in 28 lakes from 10 European countries, to assess variation in macrophyte metrics across a set of nested spatial scales: countries, lakes, sampling stations, replicate transects, and replicate samples at two depth-zones. Metrics investigated in each transect included taxa richness, maximum depth of colonisation and two indicators of trophic status: Ellenberg’s N and a metric based on phosphorus trophic status. Metrics were found to have a slightly stronger relationship to pressures when they were calculated on abundance data compared to presence/absence data. Eutrophication metrics based on helophytes were found not to be useful in assessing the effects of nutrient pressure. These metrics were also found to vary with the depth of sampling, with shallower taxa representing higher trophic status. This study demonstrates the complex spatial variability in macrophyte communities, the effect of this variability on the metrics, and theimplications to water managers, especially in relation to survey design.

  • 328. Dyrelius, D.
    et al.
    Elming, Sten-åke
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Bergarters fysik1985In: Geofysik, Uppsala: Svenska fysikersamfundet , 1985Chapter in book (Other (popular science, discussion, etc.))
  • 329.
    Ebenå, Gustav
    et al.
    Linköping University, Department of Biology.
    Hagberg, Jessika
    Örebro University, MTM, Department of Natural Sciences, Örebro.
    Carlsson, Erik
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Origin and distribution of low molecular weight organic acids and bacteria in a depth profile of a soil covered tailings impoundment in northern Sweden2007In: Journal of Geochemical Exploration, ISSN 0375-6742, E-ISSN 1879-1689, Vol. 92, no 2-3, p. 186-195Article in journal (Refereed)
    Abstract [en]

    The tailings at Kristineberg, northern Sweden, have a very low content of organic carbon, a feature common with many sulfidic tailing impoundments. Three different experiments were set-up to assess the role of carbon dioxide in a depth profile. Firstly, pore gas was collected in vials from ground water pipes at various points in the profile of a dry covered tailings impoundment and analyzed in the laboratory for CO2, O2, N2, H2, and CH4 contents. Secondly, pore water was extracted from tension lysimeters at various depths. This water was analyzed for numbers of bacteria (iron-oxidizing and sulfur-oxidizing, both by MPN), and low molecular weight organic acids. Thirdly, Acidithiobacillus ferrooxidans (Strain DSMZ No 1927) was grown on a mixture of irradiated tailings and sterile water. The amount of organic acids produced was monitored.The largest bacterial count of iron-oxidizing bacteria, 4.7 × 105/g tailings, was at the oxidation front, while the heterotrophic sulfur-oxidizing bacteria were mainly found in the unsaturated, oxidized zone, 2.65 × 104/g tailings. The oxidation front was also the location where the largest amount of organic acids was found in the field study (formate 0.83 mg/l and acetate 0.51 mg/l). The acetic acid found coincides with the highest count of iron-oxidizing bacteria.The intrusion of O2 and CO2 at the studied location is enough for microbiological activity, although the overall effect on AMD production is not addressed.The results from laboratory incubations indicate that the microbial community produces organic carbon with CO2 as the sole carbon source, up to 1.35 mg/l after 16 weeks measured as TOC.To conclude, we suggest that knowledge of the intrusion of both CO2 and O2 is vital for a full understanding of the microbial ecology, and thus the weathering processes, in a dry covered tailings impoundment. Hence, the CO2 produced in the till cover and entering the tailings ecosystem is crucial to the function of the ecosystem.

  • 330.
    Ecke, Frauke
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Bedömningsgrunder för makrofyter i sjöar: bakgrundsrapport2007Report (Other academic)
    Abstract [sv]

    De befintliga bedömningsgrunderna för makrofyter (BGM) i sjöar har hittills ansetts som preliminära. Dessutom motsvarade de inte kraven enligt EUs Ramdirektiv för vatten med avseende på bl.a. typanpassningen och angivna gränser mellan olika klasser av ekologisk status. I det framlagda förslaget för revideringen av BGM i enlighet med EUs Ramdirektiv för vatten, lades stor vikt vid att utöka dataunderlaget av framför allt referenssjöar. Med hjälp av olika påverkanskriterier valdes 49 referenssjöar, dvs. sjöar som ansågs vara av hög ekologisk status. Som kriterier användes markanvändning, sjösänkning, koncentrationen av näringsämnen samt pH i vattenfasen. Baserad på artsammansättningen bland makrofyterna gjordes en klusteranalys-baserad typindelning i tre grupper. Dessa tre typologigrupper kunde skiljas åt med hjälp av främst två typologivariabler, nämligen Y-koordinat och h.ö.h. De tre typologigrupperna/regionerna var sjöar S om Limes norrlandicus (LN), sjöar N om LN men under högsta kustlinjen (HK) samt sjöar N om LN och över HK. För att bestämma sjöarnas ekologiska status, beräknades indikatorvärden längs Tot-P-gradienten för alla funna makrofytarter förutom helofyter. Indikatorvärdena viktades med arternas nischbredd längs Tot-P-gradienten. För varje sjö kunde på det viset ett medianindikatorvärde, ett trofiindex, beräknas. Dessa trofiindex översattes till en femgradig skala enligt Ramdirektivets krav, dvs. de fem klasserna av ekologisk status. Denna konvertering gjordes med hjälp av Tot-P halter som prefereras av makrofytarter som ansågs karakteristiska för respektive klass av ekologisk status. På grund av bristande dataunderlag kunde gränsvärden inte beräknas mellan klasserna otillfredsställande och dålig ekologisk status. Trots ett heterogent datamaterial som är insamlat i olika syften, under olika decennier och till och med sekler och med varierande metodik mm., anses det föreslagna systemet kunna tillämpas i enlighet med EUs Ramdirektiv för vatten. Föreliggande utredning understryker dock det stora behovet av kompletterande inventeringar samt av en revidering av undersökningsmetoden för inventering av makrofyter. Det föreslagna systemet bör verifieras med datamaterial som inte användes för den här redovisade bedömningen. Därefter bör en eventuell revidering genomföras.

  • 331.
    Ecke, Frauke
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Drainage ditching at the catchment scale affects water quality and macrophyte occurrence in Swedish lakes2009In: Freshwater Biology, ISSN 0046-5070, E-ISSN 1365-2427, Vol. 54, no 1, p. 119-126Article in journal (Refereed)
    Abstract [en]

    1. We have limited knowledge of the effects of land use in general and of drainage ditching in particular on macrophyte communities in lakes. I quantified catchment land use, including drainage ditching, as well as water quality and the number of macrophyte species in 17 Swedish lakes in summer 2005.2. Land use within 1 km of the studied lakes was analysed in a geographic information system. The following variables were included: areas of forests, mires, agricultural land and urbanization, length of drainage ditches (classified according to the use of the land they drained), and shortest distance from lake to an urban area. To extract and analyse general trends in the data sets, redundancy analysis was used.3. Water quality was explained mainly by three land-use related variables: the lengths of agricultural, forest and mire ditches. The length of agricultural ditches was positively correlated with lake water conductivity, total dissolved solids, Ca, N and total organic carbon (TOC). The lengths of forest and mire ditches were positively correlated with lake water characteristics, especially TOC.4. The number of species representing different macrophyte life forms was explained by three environmental variables: conductivity, and lengths of forest and agricultural ditches. The numbers of isoetids, nymphaeids, elodeids and total obligate hydrophytes were negatively correlated with length of forest ditches. In contrast, the number of lemnids and helophytes was positively correlated with conductivity and length of agricultural ditches. Furthermore, the number of isoetids was exponentially related (negatively) to lengths of agricultural and forest ditches, indicating a threshold response to drainage ditch length.5. The results suggest that effects on water quality and macrophyte communities result from drainage ditching in the lake catchments rather than from land use itself. Given the total area of drainage-ditched land worldwide (millions of ha in Scandinavia alone), drainage ditching should be considered when evaluating environmental impacts on lake water quality and macrophyte occurrence and when determining reference conditions for catchment land use.

  • 332.
    Ecke, Frauke
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Effects of landscape patterns on small mammal abundance2003Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Several studies indicate a long-term decline in the numbers of voles in northern Fennoscandia. Altered land use and forest management practices have been proposed as possible causes of the decline. This doctorial thesis aimed to identify, on different spatial scales, landscape patterns that are important for the abundance of small mammals and that might be related to the decline. General trends and aspects of spatial habitat modelling were reviewed. Trapping data from three large extent monitoring programs were related to habitat factors on different spatial scales. For these analyses, a broad range of statistical and GIS (geographic information system) related methods was applied. On the microscale (trapping station, extent <= 10 m) and mesoscale (transect, length 90 m), structural habitat factors such as coarse and fine woody debris, umbrella vegetation and structural complexity of the forest floor were identified as important factors influencing small mammal abundance. Small mammal densities were related to the percentage landcover of vegetation types on the micro-, meso-, macro- (subarea/landscape, 1 x 1, 2.5 x 2.5 and 2 x 5 km) and regional scale (overall study area, 20 x 20 - 80 x 80 km). The spatial continuity (non- fragmentation) of old-growth pine forest patches on the landscape scale was positively related to the abundance of C. rufocanus, the species that showed the most pronounced long-term decline in numbers. The results of this thesis strongly suggest that altered land use might indeed be involved in the decline in numbers of voles in managed forest areas in northern Fennoscandia. To reveal and test responses of small mammals to changes in landscape patterns in more detail, this work proposes further application of large scale approaches. These approaches, e.g. the GIS-based prediction of the areas with currently high abundance of C. rufocanus can be tested by field sampling of the type applied in this thesis. Such approaches should consider the key aspects identified in the reviews on GIS-based habitat modelling, e.g. reconciling the scale of the population dynamics of small mammals with the scale (resolution and extent) of the input data, the application of different modelling approaches and the performance of sensitivity analysis.

  • 333.
    Ecke, Frauke
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    En botanisk vårresa genom Japan1999In: Nordrutan, ISSN 1401-3533, no 2Article in journal (Other academic)
  • 334.
    Ecke, Frauke
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Herman Svenonius: från vattenpest till borsting1998In: Nordrutan, ISSN 1401-3533, no 2Article in journal (Other academic)
  • 335.
    Ecke, Frauke
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    I Herman Svenonius fotspår1998In: Nordrutan, ISSN 1401-3533, no 3Article in journal (Other academic)
  • 336.
    Ecke, Frauke
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Population dynamics of small mammals in relation to habitat factors in natural and managed forests2000Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The influence of forest age and structural habitat factors on species richness and the population dynamics of small mammals were evaluated. Small mammals were monitored both in old-growth and in immature managed forests, and habitat factors were recorded.Species richness and population dynamics of forest dwelling small mammal species were positively influenced by factors related to cover of vegetation in the field layer and to structural heterogeneity in the forest floor. In contrast, species richness and the overall abundance of Clethrionomys glareolus were negatively related to forest age. However, habitats in old forests were important refuges for the winter survival of C. glareolus and therefore may forest management practices, like clearcutting, enhance population fluctuations in this species. The contrasting effects of forest age indicate that population dynamics were primarily not related to the age of forests, but rather to habitat factors important to reproduction and survival of small mammals.

  • 337.
    Ecke, Frauke
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Småsvalting - en doldis i Norrbotten1997In: Nordrutan, ISSN 1401-3533, no 1Article in journal (Other academic)
  • 338.
    Ecke, Frauke
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Sällsynta soptippssvampar1997In: Nordrutan, ISSN 1401-3533, no 1Article in journal (Other academic)
  • 339.
    Ecke, Frauke
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Utvärdering av metoder för makrofytinventering2007Report (Other academic)
    Abstract [sv]

    Vattenvegetation används nationellt och internationellt som indikator för att bedöma miljötillståndet, till exempel vattenkvalitet och naturvärden i sjöar och vattendrag. Det är av stor vikt att resultaten och analyserna från en makrofytinventering håller hög och tillförlitlig kvalitet. Den bedömning som grundar sig på kvalitetsfaktorn makrofyter kan få långtgående och kostsamma konsekvenser. Trots den stora mångfalden bland syften med makrofytinventeringar och tillgängliga inventeringsmetoder finns det i dagsläget ingen omfattande studie som har utvärderat olika inventeringsmetoder för makrofyter med avseende på en avvägning mellan syfte, karteringsmetodik, kvantifiering och resursbehov. Syftet med föreliggande utvärdering är att, baserat på en litteraturstudie och utvärdering av befintliga data, kunna rekommendera ett fåtal metoder för övervakningsinventering av sjöar för vidare fälttest. Utvärderingen bygger på en genomgång av relevant nationell och internationell litteratur, diskussioner med kollegor verksamma inom det europeiska interkalibreringsarbetet kring bedömningen av ekologisk status enligt Ramdirektivet för vatten, samt en utvärdering av tillgängliga men hittills icke utvärderade, svenska makrofytdata. Studien har avgränsats till övervakningsinventering enligt Ramdirektivet för vatten och bedömning av naturvärden. Den mest lovande metoden (enligt min bedömning) är krattning längs virtuella transekter med notering av täckningsgrad enligt en semikvantitativ skala. Metoden borde emellertid testas i minst 16 sjöar av olika biologisk och morfologisk karaktär. I ett antal sjöar (minst sex sjöar, t.ex. tre oligotrofa djupa och tre eutrofa grunda sjöar), bör krattmetoden jämföras med snorkling samt även med rutinventering med hjälp av dykning längs transekter. Dykningsmetoden är internationellt sett den mest använda övervakningsmetoden. För att undvika att de svenska data från en kommande miljöövervakningsmetod, baserad på krattmetoden, kommer att ifrågasättas, borde dykningsmetoden värderas mot krattningsmetoden. Hypotesen är att krattmetoden ger lika pålitliga resultat för bedömningen av vattenkvalitet enligt Ramdirektivet för vatten och bedömning av naturvärden som dykningsmetoden, i alla fall i de grunda sjöpartierna. Detta är dock bara ett antagande och bör verifieras med en gedigen fältstudie. Utvärderingen krävs för att kunna rekommendera krattmetoden baserat på vetenskaplig grund. Metoderna bör fälttestas under sommaren 2007, med fördel enligt faktorisk design, där hänsyn tas speciellt till sjöarnas trofistatus, bottensubstrat, sjödjup och sjöstorlek, samt med krav på att belägga effekten av antal undersökta transekter, olika typer av kratta, olika kvantifieringsmetoder, förhållandet mellan informationsvinst och resursbehov vid användning av olika karterings- och kvantifieringsmetoder.

  • 340.
    Ecke, Frauke
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Vattenvegetation som indikator för vattenkvalitet och sjökaraktär: baserad på förändringar i vattenkemi och vegetation i svenska sjöar 1929 - 20052006Report (Other academic)
    Abstract [en]

    Water vegetation as indicator of water quality and lake character - Based on changes in water chemistry, and vegetation in Swedish lakes 1929 - 2005In the 1930ies, Gunnar Lohammar analyzed macrophyte vegetation and biogeochemistry in 151 Swedish lakes. These data completed with data from resampling open up a unique opportunity to study the relation among macrophytes, biogeochemistry and land-use. 17 of the Lohammar-lakes were re-sampled in summer 2005 (eight in the county of Uppland and nine in Norrbotten) to understand these relations and their temporal changes. Macrophytes showed clear preferences along the biogeochemical gradients. The response of isoetids and lemnids along the gradients was consistent within respective group. In contrast, within elodeids and nymphaeids, species showed varying responses. The preferences were used to develop preliminary macrophyte-based indicator-values. These deviated from the English indicator-values that are used in Sweden at present. Macrophyte vegetation, biogeochemistry and land-use changed considerably from 1930 - 2005. Analysing the whole material, only the number of nymphaeid-speices changed 1930 - 2005. Differences in macrophyte abundance were most obvious between the two regions. Lakes in Norrbotten had more isoetid-species than Uppland whereas for lemnids the situation was the opposite in the 1930ies. The differences between the regions were more pronounced 2005 than 1930 and could be explained with increased nutrient concentrations in general and increased tot-N concentrations in specific. Nutrient concentrations (mainly tot-N, but also tot-Na and conductivity) increased in Uppland and Norrbotten and were explained by amongst others increased N-deposition and increased use of salt in traffic and households. Tot-P concentrations did not change significantly between 1930 - 2005 but showed a correlation to the land-use in respective drainage area, e.g. distance to nearest village. Macrophyte abundance and lake biogeochemistry were related to land-use within drainage areas and within 1-km buffer zones from the lakes. Remarkable is especially the positive correlation of the length of ditches as well as area of agricultural land and the number of macrophyte species that prefer nutrient rich environments. Macrophyte abundance could be explained by a combination of land-use and lake biogeochemistry. The increased area of clear-cuts during the study period resulted probably in a decreased number of species preferring nutrient poor environments and low TOC-concentrations. Correlations among macro- and trace element fractionation indicate that it might be the bioavailable fraction of the elements that might determine the abundance of lemnids. The results illustrate the effects of land-use and land-use change on macrophytes and biogeochemistry. The results should be regarded as a first step to better understand the link among land-use, macrophytes and biogeochemistry.

  • 341.
    Ecke, Frauke
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Christensen, Pernilla
    Hörnfeldt, Birger
    Identification of suitable spatial scales for analyzing landscape responses of grey-sided voles2005In: Abstracts, IX International Mammalogical Congress, 2005, p. 149-Conference paper (Other academic)
  • 342.
    Ecke, Frauke
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Christensen, Pernilla
    Rentz, Ralf
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Hörnfeldt, Birger
    Do landscape properties matter for densities of the grey-sided vole?: a comparison among managed and pristine forest landscapes2007In: 5. European Congress of Mammology, 2007, Vol. 2, p. 467-467Conference paper (Other academic)
  • 343.
    Ecke, Frauke
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Christensen, Pernilla
    Department of Forest Resource Management and Geomatics, Swedish University of Agricultural Sciences, Umeå.
    Rentz, Ralf
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Nilsson, Mats
    Department of Forest Resource Management and Geomatics, Swedish University of Agricultural Sciences, Umeå.
    Sandström, Per
    Department of Forest Resource Management and Geomatics, Swedish University of Agricultural Sciences, Umeå.
    Hörnfeldt, Birger
    Department of Forest Resource Management and Geomatics, Swedish University of Agricultural Sciences, Umeå.
    Landscape structure and the long-term decline of cyclic grey-sided voles in Fennoscandia2010In: Landscape Ecology, ISSN 0921-2973, E-ISSN 1572-9761, Vol. 25, no 4, p. 551-560Article in journal (Refereed)
    Abstract [en]

    Changes in forest landscape structure have been suggested as a likely contributing factor behind the long-term decline in the numbers of cyclic grey-sided voles (Clethrionomys rufocanus) in northern Fennoscandian lowland regions in contrast to mountain regions due to the absence of forest management in the mountains. This study, for the first time, formally explored landscape structure in 29 lowland (LF) and 14 mountain forest (MF) landscapes (each 2.5 × 2.5 km) in northern Sweden, and related the results to the cumulated spring trapping index of the grey-sided vole in 2002-2006. The grey-sided vole showed striking contrasts in dynamics close in space and time. The MF landscapes were characterized by larger patches and less fragmentation of preferred forest types. The grey-sided vole was trapped in all of 14 analyzed MF landscapes but only in three out of 29 of the LF landscapes. MF and LF landscapes with grey-sided vole occurrence were characterized by similar focal forest patch size (mean 357 ha, minimum 82 ha and mean 360 ha, minimum 79 ha, respectively). In contrast, these MF compared to the LF landscapes were characterized by larger patches of preferred forest types and less fragmented preferred forest types and by a lower proportion of clear-cut areas. The present results suggest that landscape structure is important for the abundance of grey-sided voles in both regions. However, in the mountains the change from more or less seasonal dynamics to high-amplitude cycles between the mid 1990s and 2000s cannot be explained by changes in landscape structure.

  • 344.
    Ecke, Frauke
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Christensen, Pernilla
    Department of Ecology and Environmental Science, Umeå University.
    Sandström, Per
    Department of Forest Resource Management and Geomatics, Swedish University of Agricultural Sciences, Umeå.
    Hörnfeldt, Birger
    Department of Ecology and Environmental Science, Umeå University.
    Identification of landscape elements related to local declines of a boreal grey-sided vole population2006In: Landscape Ecology, ISSN 0921-2973, E-ISSN 1572-9761, Vol. 21, no 4, p. 485-497Article in journal (Refereed)
    Abstract [en]

    Several studies indicate a long-term decline in numbers of different species of voles in northern Fennoscandia. In boreal Sweden, the long-term decline is most pronounced in the grey-sided vole (Clethrionomys rufocanus). Altered forest landscape structure has been suggested as a possible cause of the decline. However, habitat responses of grey-sided voles at the landscape scale have never been studied. We analyzed such responses of this species in lowland forests in Västerbotten, northern Sweden. Cumulated spring densities representing 22 local time series from 1980-1999 were obtained by a landscape sampling design and were related to the surrounding landscape structure of 2.5×2.5 km plots centred on each of the 22 1-ha trapping plots. In accordance with general knowledge on local habitat preferences of grey-sided voles, our study supported the importance of habitat variables such as boulder fields and old-growth pine forest at the landscape scale. Densities were negatively related to clear cuts. Habitat associations were primarily those of landscape structure related to habitat fragmentation, distance between habitat patches and patch interspersion rather than habitat patch type quantity. Local densities of the grey-sided vole were positively and exponentially correlated with spatial contiguity (measured with the fragmentation index) of old-growth pine forest, indicating critical forest fragmentation thresholds. Our results indicate that altered land use might be involved in the long-term decline of the grey-sided vole in managed forest areas of Fennoscandia. We propose two further approaches to reveal and test responses of this species to changes in landscape structure.

  • 345.
    Ecke, Frauke
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Christensen, Pernilla
    Umeå universitet.
    Sandström, Per
    SLU.
    Nilsson, Mats
    Department of Forest Resource Management and Geomatics, Swedish University of Agricultural Sciences, Umeå.
    Hörnfeldt, Birger
    Umeå universitet.
    Decline of grey-sided voles in managed boreal forests tracks long-term habitat fragmentation2006In: Book of Abstracts, 2006, p. 24-25Conference paper (Other academic)
    Abstract [en]

    There has been a long-term decline, causing frequent local extinctions, of cyclic grey-sided voles (Clethrionomys rufocanus) in northern Fennoscandia since 1971. Previous studies supported the hypothesis that altered landscape structure, especially in terms of forest patch area and fragmentation of oldgrowth forest, has contributed to the decline. Since those studies were based on cumulated vole time series data and static landscape structure, we now tested whether the long-term decline was related to a gradual change. We digitized landcover types (>0.25 ha) from aerial photographs within 6.25 km2 squares centred on each of the 27 sampling sites with 5 year intervals, starting in 1970. Because of clear-cutting, mean area of the patches of >35 year old forest that intersected the sampling sites decreased from 126 ha in 1970 to 44 ha in 2004. The main decrease in focal forest patch area occurred in 198085, coinciding with the major drop in vole numbers. Our results strongly suggest that long-term habitat fragmentation is involved in the current decline of grey-sided voles. However, climate change leading to warmer winters with a less stable snow cover is also thought to be of major importance, as indicated by a decrease in vole wintering success.

  • 346.
    Ecke, Frauke
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Christensen, Pernilla
    Sandström, Per
    Nilsson, Mats
    Department of Forest Resource Management and Geomatics, Swedish University of Agricultural Sciences, Umeå.
    Hörnfeldt, Birger
    Is the long-term decline of the grey-sided vole in boreal Sweden caused by gradual habitat destruction at the landscape scale?2007In: 5. European Congress of Mammology, 2007, Vol. 2, p. 468-468Conference paper (Other academic)
  • 347.
    Ecke, Frauke
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Christensen, Pernilla
    Sandström, Per
    Nilsson, Mats
    Department of Forest Resource Management and Geomatics, Swedish University of Agricultural Sciences, Umeå.
    Hörnfeldt, Birger
    Kan gråsidingens populationsnedgång förklaras med tidsserier av vegetationsdata?2006In: För en ekologiskt hållbar samhällsplanering: Abstract- sammanställning, 31 oktober 2006 Stockholm, 2006, p. 11-Conference paper (Other academic)
  • 348.
    Ecke, Frauke
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Christensen, Pernilla
    Sandström, Per
    Nilsson, Mats
    Hörnfeldt, Birger
    Spatio-temporal patterns in landscape structure cause limiting thresholds for the abundance of declining grey-sided voles2009Conference paper (Other academic)
    Abstract [en]

    The grey-sided vole (Myodes rufocanus) is one of the keystone vole species for ecosystem functioning in boreal forests. In 1970-2008 there has been a long-term decline in the numbers of grey-sided voles within a 100×100 km2 study area in northern Sweden. Habitat destruction is regarded as a contributing factor to the decline. However, we have so far lacked knowledge on any spatiotemporal thresholds in landscape structure related to the decline. Here, we studied such thresholds in 16 5×5 km landscapes, systematically distributed within the study area. Local declines were most pronounced in the western (inland) part of the study area in 1980-85. At that time, the species already had gone extinct in the eastern (coastal) area. We related changes in landscape structure to the timing of the grey-sided vole declines. Landcover types (>0.25 ha) were digitized from aerial photographs within the 5×5 km landscapes with 5-yr intervals. The most pronounced changes in landscape structure were related to changes in forest age structure due to clear-cutting. Within the study area, there were significant geographical differences in the size distribution of clearcuts and forest patches. In 1970, the coastal in contrast to the inland study area, was characterized by more clear-cuts (766  versus 182) that were smaller (mean 5 ± 18 ha versus 13 ± 34 ha) but covered larger areas (sum 4077 ha versus 2325 ha). Spatio-temporal comparisons showed that the coastal landscape in 1970, when the vole was rarely found there, resembled the inland landscape in 1985. The main decrease in focal forest patch size in the inland occurred in 1980-85, coinciding with the major drop in vole numbers there. Our results suggest that spatio-temporal changes in landscape structure are important and contributing to declines in greysided vole abundance.

  • 349.
    Ecke, Frauke
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Engström, Emma
    Rentz, Ralf
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Husson, Eva
    Sediment and water interactions with macrophyte element concentrations and community structure2009Conference paper (Other academic)
    Abstract [en]

    Littoral interactions among sediment, water and macrophytes are poorly understood. In particular there is a gap in knowledge concerning the importance of macrophytes as sinks and sources of trace elements. Such knowledge is however central for, amongst others, explaining potential mechanisms behind the community structure of macrophytes and for the development of macrophyte-based indicator values. We studied the interactions between the three matrices (sediment, water and macrophytes) at 19 sampling sites in Storträsket, a 1.7 km2 boreal lake at the land uplift coast of Northern Sweden in summer 2008. The catchment of Storträsket was dominated  by coniferous forest of mainly the dwarf-shrub type and open wet mires. The upper sediment layers (0-6 cm) were dominated by fine detritus. Fine detritus dominated also the lower layers (>6 cm but ≤10 cm) at all but four of the studied localities where fine sediments (particle diameter <0.2 mm) dominated. Sediment and water element concentrations were related to element concentrations in the dominating macrophyte species, viz. Nuphar lutea (roots and leaves), Potamogeton natans (leaves) and Sparganium angustifolium (leaves) and to chlorophyll concentrations using uni- and multivariate statistics. We studied 27 major and trace elements. Estimations of abundance and biomass of N. lutea in eight bays was based on the evaluation of high resolution (2 cm) aerial photographs. The total biomass of N. lutea and standardized biomass (biomass per unit of area) differed significantly among bays. Also concentrations in all matrices as well as in chlorophyll showed significant spatial variation in the lake. N. lutea showed for several elements significant partitioning of elements between roots and leaves (e.g. Ca, K, Na, Fe, Pb, Zn). Correlations between element concentrations in sediment/water and in macrophytes were in general weak but significant for amongst others Si in water and leaves of P. natans and Co, Cu and Fe in water and roots of N. lutea. Interpreting correlations of elements between the sediment and macrophytes might in our study be impeded by potential incorporation of lithogenic material in extracellular macrophyte tissue. Our study identified especially N. lutea as a major sink (during vegetation period) and source (during autumn and winter) of several major and trace elements. Interactions between the matrices, chlorophyll concentrations and macrophyte community structure are further discussed as well as the implications of our results for the development of macrophyte-based indicator values.

  • 350.
    Ecke, Frauke
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Hellsten, Seppo
    Mjelde, Marit
    Schlacke, Sabine
    Does macrophyte-based lake status assessment according to the EU Water Framework Directive conflict with the EU Habitat Directive in Fennoscandia?2009In: Aquatic Weeds 2009: Proceedings of the 12th European Weed Research Society Symposium, August 24-28 2009 / [ed] Arnold Pieterse; Anne-Marie Rytkönen; Seppo Hellsten, Edita Publishing Oy, 2009, Vol. 15, p. 65-Conference paper (Other academic)
    Abstract [en]

    Recently, many member states of the European Union (EU) have finalised and implemented national systems for water quality assessment in lakes according to the EU Water Framework Directive (WFD). It is however unknown how the assessment of ecological status, according to the WFD, relates to the status of lakes according to the EU Habitat Directive (HD). High ecological status according to the WFD should mean high status according to the HD. To avoid any conflicts between different EU directives and national environmental objectives, surface waters protected as for example Natura 2000 sites should ideally show high ecological status according to the WFD. Also, high ecological status according to the WFD should imply the presence or potential for presence of red-listed species. Here, we studied the ecological status of 1014 Fennoscandian lakes (224 Norwegian, 491 Swedish and 299 Finnish lakes) according to the WFD and related it to the number of red-listed species per lake and to the status of the lakes as Natura 2000 areas. High ecological status according to the WFD did not mean high status according to the HD or according to national environmental objectives. In general, the number of red-listed species decreased with increased ecological quality ratios. In Norway 47%, in Sweden 78%, and in Finland 29% of lakes with red-listed species were classified as lakes of moderate or worse ecological status according to the WFD. In Sweden 39 of 68 studied Natura 2000 lakes had a moderate or poor ecological status according to the WFD. In Sweden and Norway, in contrast to Finland, macrophyte-based assessment systems are primarily a trophic index, i.e. penalising lakes with elevated phosphorous concentrations. The multimetric nature of the Finnish index probably contributes to the better agreement between the WFD assessment and the number of red-listed species in Finland compared to Sweden and Norway. In Sweden six of eight red-listed species occur in lakes with phosphorous concentrations considerably above reference conditions. Generally, it is assumed that biodiversity is favoured by intermediate nutrient concentrations. In addition, instead of phosphorous, Ca concentrations appear important for the occurrence of many redlisted species, especially for Charophytes. Rapid revision of the national indices is needed to increase compatibility between the two EU directives and to increase the agreement between the WFD and national environmental objectives.

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