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  • 1.
    Ahlgren, Sara
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi och kvartärgeologi (INK).
    Changes in size distribution of lakes in the Nadym catchment, northern Russia2012Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Because of climate change and resource development there is an ongoing increase in the attention directed towards high latitude areas. Over the last years, warming in the Arctic has accelerated quickly. The warming climate can possibly lead to thawing of ground ice, which in turn leads to alterations of the cryosphere. This can have a huge influence on the terrestrial hydrology of the Arctic and, more specifically, on the presence and distribution of lakes in arctic regions since both are coupled to subsurface ice. In this thesis data from remote sensing were used to look at the change in the size distribution of lakes for the Nadym catchment in northern Russia. The aim was to find out if there has been an increase or decrease in the number of lakes in the area over the past years. Results suggest that there were 229 lakes less (representing a 4% decrease) in 2007–2009 compared to 1987, indicating that lakes are slowly disappearing. Also, the total lake surface area decreased with 5%. Almost half of the lakes that disappeared (49%) can be found among the smallest lakes ranging between 10–20 ha. In the entire catchment this size class was also found to be the class with by far the highest number of lakes.

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    fulltext
  • 2.
    Ahlqvist, Ola
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi och kvartärgeologi (INK).
    Context Sensitive Transformation of Geographic Information2000Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    This research is concerned with theoretical and methodological aspects of geographic information transformation between different user contexts. In this dissertation I present theories and methodological approaches that enable a context sensititve use and reuse of geographic data in geographic information systems.

    A primary motive for the reported research is that the patrons interested in answering environmental questions have increased in number and been diversified during the last 10-15 years. The interest from international, national and regional authorities together with multinational and national corporations embrace a range of spatial and temporal scales from global to local, and from many-year/-decade perspectives to real time applications. These differences in spatial and temporal detail will be expressed as rather different questions towards existing data. It is expected that geographic information systems will be able to integrate a large number of diverse data to answer current and future geographic questions and support spatial decision processes. However, there are still important deficiencies in contemporary theories and methods for geographic information integration

    Literature studies and preliminary experiments suggested that any transformation between different users’ contexts would change either the thematic, spatial or temporal detail, and the result would include some amount of semantic uncertainty. Consequently, the reported experiments are separated into studies of change in either spatial or thematic detail. The scope concerned with thematic detatil searched for approaches to represent indiscernibility between categories, and the scope concerned with spatial detail studied semantic effects caused by changing spatial granularity.

    The findings make several contributions to the current knowledge about transforming geographic information between users’ contexts. When changing the categorical resolution of a geographic dataset, it is possible to represent cases of indiscernibility using novel methods of rough classification described in the thesis. The use of rough classification methods together with manual landscape interpretations made it possible to evaluate semantic uncertainty in geographic data. Such evaluations of spatially aggregated geographic data sets show both predictable and non-predictable effects. and these effects may vary for different environmental variables.

    Development of methods that integrate crisp, fuzzy and rough data enables spatial decision support systems to consider various aspects of semantic uncertainty. By explicitly representing crisp, fuzzy and rough relations between datasets, a deeper semantic meaning is given to geographic databasses. The explicit representation of semantic relations is called a Geographic Concept Topology and is held as a viable tool for context transformation and full integration of geographic datasets.

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    FULLTEXT01
  • 3. Anderson, Lloyd B.
    et al.
    Hönisch, Bärbel
    Coxall, Helen K.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för geologiska vetenskaper. Stockholms universitet, Naturvetenskapliga fakulteten, Bolincentret för klimatforskning (tills m KTH & SMHI).
    Bolge, Louise
    Atmospheric CO2 Estimates for the Late Oligocene and Early Miocene Using Multi-Species Cross-Calibrations of Boron Isotopes2024Ingår i: Paleoceanography and Paleoclimatology, ISSN 2572-4517, E-ISSN 2572-4525, Vol. 39, nr 1, artikel-id e2022PA004569Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The boron isotope (δ11B) proxy for seawater pH is a tried and tested means to reconstruct atmospheric CO2 in the geologic past, but uncertainty remains over how to treat species-specific calibrations that link foraminiferal δ11B to pH estimates prior to 22 My. In addition, no δ11B-based reconstructions of atmospheric CO2 exist for wide swaths of the Oligocene (33–23 Ma), and large variability in CO2 reconstructions during this epoch based on other proxy evidence leaves climate evolution during this period relatively unconstrained. To add to our understanding of Oligocene and early Miocene climate, we generated new atmospheric CO2 estimates from new δ11B data from fossil shells of surface-dwelling planktic foraminifera from the mid-Oligocene to early Miocene (∼28–18 Ma). We estimate atmospheric CO2 of ∼680 ppm for the mid-Oligocene, which then evolves to fluctuate between ∼500–570 ppm during the late Oligocene and between ∼420–700 ppm in the early Miocene. These estimates tend to trend higher than Oligo-Miocene CO2 estimates from other proxies, although we observe good proxy agreement in the late Oligocene. Reconstructions of CO2 fall lower than estimates from paleoclimate model simulations in the early Miocene and mid Oligocene, which indicates that more proxy and/or model refinement is needed for these periods. Our species cross-calibrations, assessing δ11B, Mg/Ca, δ18O, and δ13C, are able to pinpoint and evaluate small differences in the geochemistry of surface-dwelling planktic foraminifera, lending confidence to paleoceanographers applying this approach even further back in time.

  • 4.
    Andersson, Erik
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Enqvist, Johan
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Tengö, Maria
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Stewardship in Urban Landscapes2017Ingår i: The Science and Practice of Landscape Stewardship / [ed] Claudia Bieling, Tobias Plieninger, Cambridge University Press, 2017, s. 219-221Kapitel i bok, del av antologi (Refereegranskat)
  • 5. Andersson, Hans
    et al.
    Widgren, MatsStockholms universitet, Samhällsvetenskapliga fakulteten, Kulturgeografiska institutionen.
    Kan man leva på en ödegård? Huvudgårdar, landbotorp och odlingssystem under medeltid i Lägerbobygden, Östergötland2016Samlingsverk (redaktörskap) (Refereegranskat)
    Abstract [en]

    Is it possible to survive on a deserted farm: Manors, tenants and farming systems during the Middle Ages in the Lägerbo area, Östergötland. 

    This study approaches the late medieval farm desertion from a landscape perspective. It focuses on the area of a former medieval estate in southern Östergötland, Sweden. Based on a retrogressive analysis of cadastral maps and historical records the medieval settlement is reconstructed. In this process three formerly unknown deserted farms were identified, with abandoned field systems and building remains.  The volume provides the archaeological documentation of field systems and settlements at these sites. These data provide the background for investigating the shifting social and ecological circumstances that once made it possible for tenant families to survive on these farms. During the height of the manorial system the small farms were specialised units in a redistributive system. In the late 14th century the estate and all tenant farms were donated to the convents of Vadstena and Vreta.  Rents were no longer paid in labour but in butter.  In the fifteenth century several farms were abandoned and turned into meadows under the surviving farms. The new tenurial relations prevented the recolonization of the farms. The study is the result of an interdisciplinary project involving medieval archaeology, historical geography, palynology and medieval history.

  • 6.
    Andrén, Cecilia
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap.
    IKEU 2008 surstötar i vattendrag: Årsrapport episoder2009Rapport (Övrigt vetenskapligt)
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    fulltext
  • 7.
    Andrén, Cecilia
    Stockholms universitet.
    Provningsjämförelser av aluminiumfraktioner: 2001 & 20022003Rapport (Övrigt vetenskapligt)
    Ladda ner fulltext (pdf)
    fulltext
  • 8.
    Andrén, Cecilia
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap.
    Studier av episodisk försurning i IKEU-projektet2005Rapport (Övrigt vetenskapligt)
    Ladda ner fulltext (pdf)
    fulltext
  • 9.
    Andrén, Cecilia M.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap.
    IKEU - Specialprojekt S9: Episoder i vattendrag2006Rapport (Övrigt vetenskapligt)
    Ladda ner fulltext (pdf)
    fulltext
  • 10.
    Andrén, Cecilia M.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap.
    Jarlman, Amelie
    Bentiska kiselalger som surhetsindikatorer i rinnande vatten2006Rapport (Övrigt vetenskapligt)
    Ladda ner fulltext (pdf)
    fulltext
  • 11.
    Ango, Tola Gemechu
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Kulturgeografiska institutionen.
    Hylander, Kristoffer
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Börjeson, Lowe
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Kulturgeografiska institutionen.
    Processes of Forest Cover Change since 1958 in the Coffee-Producing Areas of Southwest Ethiopia2020Ingår i: Land, E-ISSN 2073-445X, Vol. 9, nr 8, artikel-id 278Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We investigated the spatial relations of ecological and social processes to point at how state policies, population density, migration dynamics, topography, and socio-economic values of ‘forest coffee’ together shaped forest cover changes since 1958 in southwest Ethiopia. We used data from aerial photos, Landsat images, digital elevation models, participatory field mapping, interviews, and population censuses. We analyzed population, land cover, and topographic roughness (slope) data at the ‘sub-district’ level, based on a classification of the 30 lowest administrative units of one district into the coffee forest area (n = 17), and highland forest area (n = 13). For state forest sites (n = 6) of the district, we evaluated land cover and slope data. Forest cover declined by 25% between 1973 and 2010, but the changes varied spatially and temporally. Losses of forest cover were significantly higher in highland areas (74%) as compared to coffee areas (14%) and state forest sites (2%), and lower in areas with steeper slopes both in coffee and highland areas. Both in coffee and highland areas, forest cover also declined during 1958–1973. People moved to and converted forests in relatively low population density areas. Altitudinal migration from coffee areas to highland areas contributed to deforestation displacement due to forest maintenance for shade coffee production in coffee areas and forest conversions for annual crop production in highland areas. The most rapid loss of forest cover occurred during 1973–1985, followed by 2001–2010, which overlapped with the implementations of major land and forest policies that created conditions for more deforestation. Our findings highlight how crop ecology and migration have shaped spatial variations of forest cover change across different altitudinal zones whilst development, land, and forest policies and programs have driven the temporal variations of deforestation. Understanding the mechanisms of deforestation and forest maintenance simultaneously and their linkages is necessary for better biodiversity conservation and forest landscape management.

    Ladda ner fulltext (pdf)
    fulltext
  • 12.
    Aronsson, Johanna
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi.
    Användning av tredimensionell geologisk modellering i hydrogeologiska utredningar: En fallstudie inför anläggandet av ett akviferlager i Brunkebergsåsen i Stockholm2015Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Akviferlager är en form av geoenergi där solenergi lagrad i grundvattnet används för att värma och kyla byggnader. Inför anläggandet av ett akviferlager är det viktigt med grundläggande geologiska och hydrogeologiska utredningar för att säkerställa funktion och kapacitet hos akviferlagret, samt minimera eventuell miljöpåverkan. I denna studie utvecklas en tredimensionell geologisk modell för att öka kunskapen om rullstensåsens geologiska uppbyggnad samt bedöma hur geologin kan komma att påverka det planerade akviferlagret. För att undersöka vilken påverkan manuella justeringar och tolkningar av geologin har, togs två geologiska modeller fram för jämförelse. Utifrån de geologiska modellerna uppskattades effektiv hydraulisk konduktivitet för åsen, d.v.s. sammanlagd konduktivitet för hela akviferens mäktighet, samt transporttid mellan akviferlagrets brunnspoler. Studien visar att akviferen består av sammanhängande jordlager med hög hydraulisk konduktivitet. Beroende på tolkningar och justeringar i modelleringsprocessen visar de två olika modellerna på skillnader vad gäller jordlagrens utbredning och mäktighet. Detta medför skillnader i effektiv hydraulisk konduktivitet mellan modellerna, vilket resulterar i relativt stora skillnader vad gäller transporttider mellan brunnspolerna. Tredimensionella geologiska modeller bedöms bidra till förbättrade hydrogeologiska utredningar då det är ett enkelt och effektivt sätt att bygga upp ett områdes geologi för översikt, tolkning och vidare studier i form av exempelvis grundvattenmodellering.

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    fulltext
  • 13.
    Backman, Jan
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för geologi och geokemi. Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för geologi och geokemi.
    Jakobsson, Martin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för geologi och geokemi. Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för geologi och geokemi.
    Frank, Martin
    Sangiorgi, F
    Brinkhuis, Henk
    Sluijs, Appy
    Stickly, Catherine
    Gattacecca, Jerome
    Age/depth relationships for the ACEX sedimentary section recovered from the Lomonosov Ridge2007Konferensbidrag (Övrig (populärvetenskap, debatt, mm))
  • 14.
    Balk, Lennart
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Hägerroth, Per-Åke
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Gustavsson, Hanna
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Sigg, Lisa
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Åkerman, Gun
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Ruiz Munoz, Yolanda
    Honeyfield, Dale C.
    Tjärnlund, Ulla
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Oliveira, Kenneth
    Ström, Karin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    McCormick, Stephen D.
    Karlsson, Simon
    Ström, Marika
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi. Karolinska Institutet, Sweden.
    van Manen, Mathijs
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi. Utrecht University, Germany.
    Berg, Anna-Lena
    Halldorsson, Halldor P.
    Strömquist, Jennie
    Collier, Tracy K.
    Börjeson, Hans
    Mörner, Torsten
    Hansson, Tomas
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Widespread episodic thiamine deficiency in Northern Hemisphere wildlife2016Ingår i: Scientific Reports, E-ISSN 2045-2322, Vol. 6, artikel-id 38821Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Many wildlife populations are declining at rates higher than can be explained by known threats to biodiversity. Recently, thiamine (vitamin B-1) deficiency has emerged as a possible contributing cause. Here, thiamine status was systematically investigated in three animal classes: bivalves, ray-finned fishes, and birds. Thiamine diphosphate is required as a cofactor in at least five life-sustaining enzymes that are required for basic cellular metabolism. Analysis of different phosphorylated forms of thiamine, as well as of activities and amount of holoenzyme and apoenzyme forms of thiaminedependent enzymes, revealed episodically occurring thiamine deficiency in all three animal classes. These biochemical effects were also linked to secondary effects on growth, condition, liver size, blood chemistry and composition, histopathology, swimming behaviour and endurance, parasite infestation, and reproduction. It is unlikely that the thiamine deficiency is caused by impaired phosphorylation within the cells. Rather, the results point towards insufficient amounts of thiamine in the food. By investigating a large geographic area, by extending the focus from lethal to sublethal thiamine deficiency, and by linking biochemical alterations to secondary effects, we demonstrate that the problem of thiamine deficiency is considerably more widespread and severe than previously reported.

  • 15.
    Barliaev, Aleftin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi.
    Paleogeography and shore displacement of Eastern Gotland between 9.5 and 2.8 ka cal BP2017Självständigt arbete på avancerad nivå (masterexamen), 40 poäng / 60 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Located in the middle part of the Baltic, the island of Gotland underwent major environmental changes, associated with different stages of the development of the basin during the Holocene, and therefore represents a promising location for shore-displacement studies. This thesis is focused on a palaeohydrological evolution of the Lina Mire, central eastern part of Gotland, in the Middle Holocene and aims to reconstruct the timing and environment of the Littorina transgression. The research is based on a multi-proxy approach and carried out, applying lithostratigraphical, biostratigraphical (diatom analysis) and geochemical methods (XRF, organic and carbonate content) along with radiocarbon dating. The initiation of the Littorina transgression was constrained at 8.5 ka cal BP, however, probably proceeded by a hiatus. A two-folded pattern oft he maximum sub-phases is suggested. Acquired results fit well with previous studies on areas with the similar rate of apparent land uplift, suggesting an average rate of 2 mm/yr for the last 2.8 ka.

    Ladda ner fulltext (pdf)
    fulltext
  • 16.
    Barnett, Jamie
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi.
    Holmes, Felicity A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi.
    Kirchner, Nina
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi. Stockholms universitet, Naturvetenskapliga fakulteten, Bolincentret för klimatforskning (tills m KTH & SMHI).
    Modelled dynamic retreat of Kangerlussuaq Glacier, East Greenland, strongly influenced by the consecutive absence of an ice mélange in Kangerlussuaq Fjord2023Ingår i: Journal of Glaciology, ISSN 0022-1430, E-ISSN 1727-5652, Vol. 69, nr 275, s. 433-444Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Mass loss at the Greenland Ice Sheet is influenced by atmospheric processes controlling its surface mass balance, and by submarine melt and calving where glaciers terminate in fjords. There, an ice mélange - a composite matrix of calved ice bergs and sea ice - may provide a buttressing force on a glacier terminus and control terminus dynamics. Kangerlussuaq Glacier is a major outlet of the Greenland Ice Sheet, for which recent major retreat events in 2004/2005 and 2016-2018 coincided with the absence of an ice mélange in Kangerlussuaq Fjord. To better understand the response of Kangerlussuaq Glacier to climatic and oceanic drivers, a 2D flowline model is employed. Results indicate that an ice mélange buttressing force exerts a major control on calving frequency and rapid retreat. When an ice mélange forms in Kangerlussuaq Fjord, it provides stabilising forces and conditions favourable for winter terminus re-advance. When it fails to form during consecutive years, model results indicate that Kangerlussuaq Glacier is primed to retreat into the large overdeepenings in Kangerlussuaq Fjord, and to terminus positions more than 30 km farther inland, implying that excessive mass loss from Kangerlussuaq Glacier by the year 2065 cannot be excluded.

  • 17. Barth, Matthias
    et al.
    Jiménez Aceituno, Amanda
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Lam, David P. M.
    Buergener, Lina
    Lang, Daniel J.
    Transdisciplinary learning as a key leverage for sustainability transformations2023Ingår i: Current Opinion in Environmental Sustainability, ISSN 1877-3435, E-ISSN 1877-3443, Vol. 64, artikel-id 101361Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Learning and transdisciplinary research are widely acknowledged as key components for achieving sustainability; however, the links between these concepts remain vague in the sustainability literature. Recently, emphasis has been given to transdisciplinary learning, highlighting its potential as an approach that contributes to solving real-world problems. To better understand and foster transdisciplinary learning for sustainability transformations, it is relevant to pay attention to two dimensions that define transdisciplinary learning: social interaction (individual learning in a social setting, as a group, or beyond the group), and learning forms (single-, double-, or triple-loop learning). This article introduces a conceptual framework built upon these two dimensions to understand three specific forms of transdisciplinary learning as a) individual competence development, b) experience-based collaboration, and c) societal interaction. This framework helps to clarify the design of learning processes as well as their interactions in transdisciplinary processes to support transformative change.

  • 18. Belton, Lydia E.
    et al.
    Cameron, Elissa Z.
    Dalerum, Fredrik
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. University of Pretoria, South Africa; University of Oviedo, Spa.
    Spotted hyaena space use in relation to human infrastructure inside a protected area2016Ingår i: PeerJ, E-ISSN 2167-8359, Vol. 4, artikel-id e2596Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Increasing human population growth has led to elevated levels of human-carnivore conflict. However, some carnivore populations have adapted to urban environments and the resources they supply. Such associations may influence carnivore ecology, behaviour and life-history. Pockets of urbanisation sometimes occur within protected areas, so that anthropogenic influences on carnivore biology are not necessarily confined to unprotected areas. In this study we evaluated associations between human infrastructure and related activity and space use of spotted hyaenas within one of the largest protected areas in South Africa, the Kruger National Park. Home range size was smaller for the dominant female of a clan living in close proximity to humans than that of the dominant female of a clan without direct access to human infrastructure. The home range including human infrastructure was also used less evenly during the night, presumably when the animals were active. Within this home range, a village area was preferred during the night, when the least modified areas within the village were preferred and administration and highly modified areas were avoided. During the day, however, there were no preference or avoidance of the village area, but all habitats except unmodified habitats within the village area were avoided. We suggest that human infrastructure and associated activity influenced hyaena space use, primarily through alterations in the spatial distribution of food. However, these effects may have been indirectly caused by habitat modification that generated favourable hunting habitat rather than a direct effect caused by access to human food such as garbage. Because of the often pivotal effects of apex predators in terrestrial ecosystems, we encourage further work aimed to quantify how human presence influences large carnivores and associated ecosystem processes within protected areas.

  • 19.
    Bignert, Anders
    Stockholms universitet.
    Biological aspects and statistical methods to improve assessments in environmental monitoring2003Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
  • 20.
    Bjursäter, Stefan
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi och kvartärgeologi (INK).
    Borrning efter interstadiala sediment vid Ultevisplatån, Norrbotten2013Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The purpose of this study is to find datable interstadial sediments in the core area of the LateWeicheslian ice sheet extent. Based on geomorphological evidence, three coring sites wereidentified close to the Ultevis plateau in Norrbotten, northern Sweden. Sediment coring wascarried out in two pre-Late Weichselian stream channels and in a sediment basin. Stratigraphyfrom one of the sites, a 100 meter wide meltwater channel, was chosen for further analysis. Thestudied core was 5,93 m long and ended in a lower till unit. The core contained silt and sandbelow an upper till unit, indicating presence of interstadial sediments in the stratigraphy. Thecore was subsampled for luminescence dating. Two samples from above the upper till unit andtwo samples from below this unit were chosen for initial luminescence measurements onfeldspar. These preliminary measurements indicate a significant difference in paleodosebetween the upper samples and the lower. The upper samples displayed relatively highpaleodoses, possibly representing pre-Late Weichselian ages. This could imply presence of twointerstadials in the stratigraphy. The lower samples exhibited significantly higher paleodosesthan the upper ones, possibly indicating early-Weichselian or even Saalian ages for the lowersamples.

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    Borrning efter interstadiala sediment vid Ultevisplatån, Norrbotten
  • 21.
    Björkvald, Louise
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för geologi och geokemi. Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för geologi och geokemi. Geokemi.
    Hydrogeochemistry of Fe and Mn in small boreal catchments2007Licentiatavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    It is suggested that the overall understanding of the general hydrogeochemistry of a region is best understood from a landscape perspective. If so, this can provide useful information when planning monitoring programmes and influence of human activity. In this thesis the influence of landscape properties on iron (Fe) and manganese (Mn) is investigated.

    Iron and manganese are abundant in the Earth’s crust but occur in relatively low concentrations in most aquatic systems, due to the low solubility of their thermodynamically stable oxidation states (Fe(III) and (Mn(IV)). The hydrogeochemistry of iron and manganese is important, since their naturally occurring oxyhydroxides exhibit a strong adsorption affinity for trace elements. Moreover, the redox transformations of iron and manganese occur at pH and Eh (redox potential) boundaries found in natural waters.

    We investigated the hydrogeochemistry of iron and manganese in a boreal stream network of 15 streams, located in Västerbotten, Sweden. Water samples were collected on a frequent basis during 2004 and 2005, from 15 sub-catchments of the Krycklan catchment (67 km2). Total (unfiltered) and dissolved (<0.4µm) concentrations of iron and manganese were used to investigate the influence of landscape types (i.e. percentage cover of wetlands and forest) on the spatial and temporal variations of these elements.

    We found that iron correlates significantly with percentage of wetland and also with dissolved organic carbon (DOC). For manganese we did not observe a significant correlation with wetlands, which indicates that this element is less dependent on organic matter in comparison to iron. In particular, the correlation of the Fe/Al ratio to wetlands was highly significant (r2=0.92, p<0.01). However, principal component analyses indicate that iron, during peak discharge at spring flood, is not correlated with wetlands. During this period iron instead correlates with soil variables (i.e. silt) which highlights the importance of particulates during high discharge events.

    Since the naturally occurring oxyhydroxides have a strong adsorption affinity for other trace elements it is of great importance to further increase the knowledge of how these elements interact with iron and manganese in relation to the landscape composition. Further analyses of relations between trace metals (e.g. Cd, Co, Cr, Cu, Pb), and iron and manganese, but also between trace metals and landscape composition, will highlight the importance of studying the hydrogeochemistry from a landscape perspective.

  • 22.
    Borg, Hans
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Andrén, Cecilia
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Sundbom, Marcus
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Wilander, Anders
    Wällstedt, Teresia
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Episodförsurning - Underlag till Naturvårdsverkets handbok för kalkning av sjöar och vattendrag.2007Rapport (Övrigt vetenskapligt)
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  • 23. Borg, Hans
    et al.
    Wällstedt, Teresia
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för geologiska vetenskaper.
    Uran i kalkprodukter – beräkning av belastningen på sjöar2011Rapport (Övrigt vetenskapligt)
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    fulltext
  • 24.
    Borén, Thomas
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Kulturgeografiska institutionen.
    Meeting-places of Transformation: Urban Identity, Spatial Representations and Local Politics in St Petersburg, Russia2005Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    This study develops a model for understanding spatial change and the construction of space as a meeting-place, and then employs it in order to show an otherwise little-known picture of (sub-)urban Russia and its transformation from Soviet times to today. The model is based on time-geographic ideas of time-space as a limited resource in which forces of various kinds struggle for access and form space in interaction with each other. Drawing on cultural semiotics and the concepts of lifeworld and system, the study highlights the social side of these space-forming forces. Based on a long-term fieldwork (participant observation) in Ligovo/Uritsk, a high-rise residential district developed around 1970 and situated on the outskirts of Sankt-Peterburg (St Petersburg), the empirical material concerns processes of urban identity, spatial representations and local politics. The study explicates three codes used to form the image of the city that all relate to its pre-Revolutionary history, two textual strategies of juxtaposition in creating the genius loci of a place, and a discussion of what I call Soviet "stiff landscape" in relation to Soviet mental and ordinary maps of the urban landscape. Moreover, the study shows that the newly implemented self-governing municipalities have not realised their potential as political actors in forming local space, which raises questions on the democratisation of urban space. Finally, the study argues that the model that guides the research is a tool that facilitates the application of the world-view of time-geography and the epistemology of the landscape of courses in concrete research. The study ends with an attempt to generalise spatial change in four types.

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    FULLTEXT01
  • 25.
    Bäckström, Alexander
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för geologiska vetenskaper.
    A new digital bathymetric model of Lake Vättern, Southern Sweden2018Självständigt arbete på avancerad nivå (masterexamen), 40 poäng / 60 hpStudentuppsats (Examensarbete)
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    2018_alexander-backstrom_msc_marine-geology_60hp
  • 26.
    Bäckström, Alexander
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för geologiska vetenskaper.
    Sediment classification from backscatter analysis of multibeam data from Lake Vättern2015Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
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    fulltext
  • 27. Christian, Marcussen
    et al.
    Jakobsson, Martin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för geologi och geokemi. Marin geovetenskap.
    Lomonosov Ridge off Greenland (LOMROG) 20072007Ingår i: EOS Transactions: American Geophysical Union, v. 88(52), 2007, s. Abstract OS41C-03Konferensbidrag (Övrigt vetenskapligt)
  • 28.
    Crimella, Daniele
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Exploring future land system change in Central and Eastern Africa2017Självständigt arbete på avancerad nivå (masterexamen), 80 poäng / 120 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The Central and Eastern African region is confronted with increasing socio-economic demands and global change pressures which could in the near future threaten the sustainability of its land system. Significant land use and cover (or land system) change would critically impact nature and people both locally and globally. Yet, its action is comparatively less studied than for other parts of the world, highlighting the need to have improved information on plausible future land system change in this region.

    This work synthesised a set of underlying drivers and proximate causes of land system change in the region through a metastudy, to than conduct a scenario analysis based on identified critical uncertainties, exploring future change in this land system.

    Multiple social and biophysical underlying drivers emerged as acting on proximate causes through chains of causation, driving change in cropland, forest, infrastructure, urban, and dryland areas. Two identified critical uncertainties, global versus local economic system orientation and fragmented versus integrated regional governance, defined four plausible scenarios exploring different land system change.

    The findings of this work contribute to the understanding of plausible future change in this understudied land system, and provide the base for complementary land system research. Additionally, reported conclusions could inform policy or practice processes aimed at steering the future of this land system at a critical juncture.

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    fulltext
  • 29.
    Demina, Ludmila
    et al.
    P.P. Shirshov Institute of Oceanology, Russian Academy of Sciences.
    Holm, Nils
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för geologiska vetenskaper.
    Galkin, Sergey
    P.P. Shirshov Institute of Oceanology, Russian Academy of Sciences.
    Lein, Alla
    P.P. Shirshov Institute of Oceanology, Russian Academy of Sciences.
    Concentration function of deep-sea vent benthic organisms2010Ingår i: Cahiers de Biologie Marine, Vol. 51, s. 369-373Artikel i tidskrift (Refereegranskat)
  • 30.
    Destouni, Georgia
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi och kvartärgeologi (INK).
    The National Geosphere Laboratory2012Övrigt (Övrig (populärvetenskap, debatt, mm))
  • 31.
    Edvinsson, Johan
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi och kvartärgeologi (INK).
    Thermokarst lake expansion and infilling rates in the Tavvavuomapeat plateau complex, northern Sweden2013Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The permafrost region has recently experienced an increased attention, due to projected climatechange and resource development. In permafrost landscapes, thermokarst lakes are commonfeatures. These water-filled collapse features form when ice-rich ground thaws. Thermokarstlakes are dynamic and change naturally in size due to erosion and/or infilling of fen vegetationalong lake shorelines. When they are formed, thermokarst lakes emit large amounts of carbon inform of the greenhouse gases methane (CH4) and carbon dioxide (CO2). Quantifying rates ofthermokarst lake expansion and infilling of fen vegetation by cardinal direction can help ourunderstanding of thermokarst lake dynamics. This study quantifies rates and extent ofthermokarst lake expansion and infilling of fen vegetation by cardinal direction for the timeperiods 1963-1975 and 1975-2003, in Tavvavuoma peat plateau complex, northern Sweden.This is done using the ArcGIS extension Digital Shoreline Analysis System (DSAS). The rateswere less than 0.1 m/yr, and lake expansion was greater than infilling between 1963 and 1975.For the 1975-2003 period, infilling of fen vegetation was greater than lake expansion. Thedirectional patterns for expansion and infilling of fen vegetation could potentially explained beby wind direction for different seasons, but the patterns are far from uniform in all lakes,indicating that local properties like lake depth, lake size and shape and the surrounding peatdepth and permafrost depth and temperature also might affect the activity in the lakes.

  • 32.
    Edwards, Nathalie
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi.
    Telegrafberget & Ällmora träsk - ett potentiellt naturreservat på Brevikshalvön, Tyresö kommun2015Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Inom den regionala utvecklingsplanen av Stockholmsområdet inkluderas att mark avsätts och reserveras för bibehållande av natur-, kultur- samt rekreationsvärden. I Tyresö kommun föreslås Telegrafberget och Ällmora träsk, ett område beläget på Brevikshalvön, att bli naturreservat. Detta främst pga. det rekreativa värdet som strövområde, men även för det ekologiska värdet i ett i princip helt intakt avrinningsområde, hällmarkstallskog med flera 300 år gamla träd inkl. biotoptypisk fauna och en landskapsbild med både ett högt berg och en sjö bildad ur en förkastningsspricka. Dessutom tillkommer dess spännande historia, där arkeologiska fynd visar att människor vistats i området ända sedan stenåldern. Detta i sin tur kan ha ett pedagogiskt värde. Det finns redan ett antal naturreservat på halvön, vart och ett med sin egen specifika karaktär. Att komplettera dessa med det föreslagna området skulle innebära ytterligare bredd i ett mångsidigt litet nätverk av skyddad natur på den relativt lilla yta som halvön utgör. Det skulle i så fall vara av stort värde, inte bara för Tyresöbor, men också för övriga stockholmare och helt i linje med det regeringsuppdrag som deklarerar vikten av tätortsnära natur.

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  • 33. Ehrenfreund, Pascale
    et al.
    Spaans, Marco
    Holm, Nils G.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för geologiska vetenskaper.
    The evolution of organic matter in space2011Ingår i: Philosophical Transactions. Series A: Mathematical, physical, and engineering science, ISSN 1364-503X, E-ISSN 1471-2962, Vol. 369, nr 1936, s. 538-554Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Carbon, and molecules made from it, have already been observed in the early Universe. During cosmic time, many galaxies undergo intense periods of star formation, during which heavy elements like carbon, oxygen, nitrogen, silicon and iron are produced. Also, many complex molecules, from carbon monoxide to polycyclic aromatic hydrocarbons, are detected in these systems, like they are for our own Galaxy. Interstellar molecular clouds and circumstellar envelopes are factories of complex molecular synthesis. A surprisingly high number of molecules that are used in contemporary biochemistry on the Earth are found in the interstellar medium, planetary atmospheres and surfaces, comets, asteroids and meteorites and interplanetary dust particles. Large quantities of extra-terrestrial material were delivered via comets and asteroids to young planetary surfaces during the heavy bombardment phase. Monitoring the formation and evolution of organic matter in space is crucial in order to determine the prebiotic reservoirs available to the early Earth. It is equally important to reveal abiotic routes to prebiotic molecules in the Earth environments. Materials from both carbon sources (extra-terrestrial and endogenous) may have contributed to biochemical pathways on the Earth leading to life’s origin. The research avenues discussed also guide us to extend our knowledge to other habitable worlds.

  • 34.
    Enqvist, Johan
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Stewardship in an urban world: Civic engagement and human–nature relations in the Anthropocene2017Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Never before have humans wielded a greater ability to alter and disrupt planetary processes. Our impact is becoming so noticeable that a new geological epoch has been proposed – the Anthropocene – in which Earth systems might no longer maintain the stable and predictable conditions of the past 12 millennia. This is particularly evident in the rapid expansion of urban areas, where a majority of humans now live and where environmental changes such as rising temperatures and habitat loss are happening faster than elsewhere.  In light of this, questions have been raised about what a more responsible relationship between humans and the rest of the planet might look like. Scholars in sustainability science employ the concept of ‘stewardship’ in searching for an answer; however, with multiple different applications and definitions, there is a need to better understand what stewardship is or what novelty it might add to sustainability research. This thesis investigates stewardship empirically through two case studies of civic engagement for protecting nature in cities – Bengaluru, India and New York City, USA. Further, the thesis also proposes a conceptual framework for how to understand stewardship as a relation between humans and the rest of nature, based on three dimensions: care, knowledge and agency. This investigation into stewardship in the urban context uses a social–ecological systems approach to guide the use of mixed theory and methods from social and natural sciences. The thesis is organized in five papers. Paper I reviews defining challenges in managing urban social–ecological systems and proposes that these can more effectively be addressed by collaborative networks where public, civic, other actors contribute unique skills and abilities. Paper II and Paper III study water resource governance in Bengaluru, a city that has become dependent on external sources while its own water bodies become degraded and depleted.Paper II analyzes how locally based ‘lake groups’ are able to affect change through co-management arrangements, reversing decades of centralization and neglect of lakes’ role in Bengaluru’s water supply.Paper III uses social–ecological network analysis to analyze how patterns in lake groups’ engagements and collaborations show better fit with ecological connectivity of lakes.Paper IV employs sense of place methods to explore how personal bonds to a site shapes motivation and goals in waterfront stewardship in New York City. Finally,Paper V reviews literature on stewardship and proposes a conceptual framework to understand and relate different uses and underlying epistemological approaches in the field. In summary, this thesis presents an empirically grounded contribution to how stewardship can be understood as a human–nature relation emergent from a deep sense ofcare and responsibility, knowledge and learning about how to understand social–ecological dynamics, and theagency and skills needed to influence these dynamics in a way that benefits a greater community of humans as others. Here, the care dimension is particularly important as an underappreciated aspect of social–ecological relations, and asset for addressing spatial and temporal misalignment between management institutions and ecosystem. This thesis shows that care for nature does not erode just because green spaces are degraded by human activities – which may be crucial for promoting stewardship in the Anthropocene.

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    Stewardship in an urban world
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    Omslagsframsida
  • 35.
    Enqvist, Johan
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Campbell, Lindsay K.
    Stedman, Richard C.
    Svendsen, Erika M.
    Pathways to urban environmental stewardship: Sense of place and civic engagement for urban waterfrontsManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Participation of local residents is considered beneficial for urban environmental stewardship, but the understanding of how urban stewards relate to the places they work with is poorly developed. This study of civic groups working to steward urban waterfronts challenges the notion that stronger attachment drives deeper commitment to stewardship. The study looks at three types of groups doing stewardship work on waterfronts and water bodies in New York City: community groups, environmental groups and recreational groups. Using interviews and Likert scale surveys (n=31), we assessed stewardship activities, place attachment and place meanings that members associate with site that each group works with. Our findings show that community group members are more attached to the sites they work with than members of environmental or recreational groups, but environmental groups report the greatest effort put into stewardship work. Further, we show that place meanings reveal different categories of groups based on how they currently view the site (as a place of work, a place of home, or a place of use), and what they want to achieve for it in their stewardship work: some groups work to restore what the place was previously, others work to protect what it currently is, while a few work to create a new identity for their place. These findings demonstrate how pathways to stewardship differ and are not dependent on strong place attachment; however, they can generate fundamentally different outcomes depending on what place meanings stewardship seeks to protect.

  • 36.
    Enqvist, Johan
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Tengö, Maria
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Bodin, Örjan
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Enhancing social–ecological fit from the bottom up: Urban lake networks and grassroots innovatorsManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Urban environmental governance is often hampered by social institutions being poorly aligned with fragmented ecosystems. Bottom-up approaches have been argued to address this problem of social-ecological fit, but there is a lack of empirical understanding of how local initiatives might emerge and spread in a way that enhances fit. We study a system of hydrologically interconnected lakes in Bengaluru, which public authorities have largely failed to protect resulting in many degraded lakes and undermined societal and ecological benefits that the system of lakes provides. Local residents have, largely in response to these failures, formed lake groups and convinced municipal actors to recognize them as partners that share management responsibilities for certain lakes. These initiatives have inspired others to follow suit and work with lakes elsewhere in the city, hence triggering the question whether local lake groups in this way contribute to a better social–ecological fit at a broader landscape scale. This study mixes quantitative social–ecological network analysis with interviews to analyze fit and describe the processes by which lake management can be shaped to match ecosystem structure. Results show that certain key lake groups – enabled by supportive municipal officers – have successfully innovated how lakes are managed, acknowledging their place in and dependence on the broader network of interconnected lakes. In the wake of this, a new generation of collaborative lake groups is emerging, where lakes are often managed more holistically by recognizing them to be part of the larger network of lakes. The analysis identifies key lake groups that are instrumental to shaping the spread of the bottom-up driven initiatives in ways that aligns with the interconnected nature of the lake system. This is a process that relies on acknowledgement and support from public authorities, but is primarily driven by local actors. By describing this process of innovation and diffusion, the study contributes important lessons on how to enhance fit between governance arrangements and the ecosystem on which cities depend.

  • 37.
    Eriksson, Pia
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi och kvartärgeologi (INK).
    Modeling the effect of activelayer deepening on stocks ofsoil organic carbon in thePechora River Basin2012Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This study investigates how the estimated thickening of the active layer will affectthe soil organic carbon in permafrost soils. The focus lies on estimating how muchof the upper permafrost soil organic carbon will be affected by the active layerdeepening due to global warming, on what timescale the deepening will take placeand if the estimated changes differ depending on the extent of permafrost in theregion. A model made in a Geographic Information System (GIS) combines datasetsfrom The Northern Circumpolar Soil Carbon Database, field data of soil organiccarbon content (SOCC) in different permafrost soil horizons in the Usa basin anddata of recent and future active layer depth from a spatially distributed permafrostdynamics model in the Pechora River Basin. The model shows that in 1980, 75% ofthe available 0–100 cm Gelisol soil organic carbon mass (SOCM) has affected byseasonal thawing. In 2050 the proportion is increased to 86% and by 2090 almostthe whole study area has an active layer deeper than 1 meter (98%). This indicatesan increase from approximately 0.64% to 0.84% of the total 1–100 cm SOCM in thenorthern permafrost region. The change is more gradual in the isolated and thesporadic permafrost zones and more abrupt in the continuous and discontinuous regions.

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    Eriksson_2012
  • 38.
    Eriksson, Sandra
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi.
    Ekosystemtjänster vid dagvattenhantering: En jämförelse av öppna dagvattenlösningar i urban miljö2016Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Stormwater is a valuable resource but with climate change and changed precipitation it may cause problems in urban environments. With increasing urbanisation more land becomes exploited which can not naturally manage stormwater and solve the problems. The purpose with this study is to demonstrate the importance of green infrastructure to manage stormwater. The stormwater systems this study includes are different forms of green infrastructure; green areas, swales, ponds and wetlands. They manage stormwater, have different pros and cons and are various good at meeting the selected ecosystem services; balancing stormwater peaks, sewage treatment and groundwater recharge. Wetlands stand out as the best at meeting the ecosystem services balancing stormwater peaks and sewage treatment. Green areas are best with groundwater recharge. These areas can naturally manage stormwater and that is a strong reason to preserve and/or restore them during exploitation.

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    fulltext
  • 39.
    Erlandsson, Rasmus
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi och kvartärgeologi (INK).
    Långtida markanvändningsförändringar i jordbruket på Ingmarsö2010Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Traditionellt skötta jordbrukslandskap hyser några av Sveriges mest artrika naturtyper, i huvudsak öppna gräsmarker till vilka en stor del av Sveriges hotade kärlväxter är knutna. Jordbrukets utveckling sedan 1800-talets slut har lett till kraftig minskning av gräsmarker och sämre kvalitet hos de kvarvarande. Skärgårdsjordbruket har små möjligheter till storskalighet och har inte haft samma effektiviseringstryck på sig som jordbruk på fastlandet. Det kan alltså tänkas ha behållit äldre tiders småskalighet – i de fall det fortfarande bedrivs – och därmed stora naturvärden. Studien är en jämförelse mellan jordbrukets utveckling i skärgården och på fastlandet, baserat på GIS-analys av historiska kartdata kompletterat med fältstudier och intervjuer. Undersökningsområdena omfattar Ingmarsö i Stockholms skärgård och Myra, norr om Norrtälje. Arbetet omfattar också en GIS-baserad hävdanalys där gräsmarker klassats utifrån historisk markanvändning. Resultatet är tänkt att vara ett hjälpmedel i restaureringsprojekt genom att ringa in marker med potentiellt höga naturvärden. Reslutatet visar att skärgårdsjordbruket gått tillbaka men behållit sin småskalighet och förblivit aktivt. Till skillnad från det undersökta fastlandsjordbruket som så gott som upphörde innan 1950-talet. Hypotesen att skärgårdsjordbruket skulle vara mindre påverkat av jordbrukets allmäna utveckling bekräftas alltså, men då studien inte bygger på replikat går det inte att dra några generella slutsater. Ett flertal tänkbara förklaringar finns, bland annat skärgårdsbondens bredare försörjningsbas med möjlighet till fiske och intäkter från sommargäster. Hävdanalysen ringar in ett flertal områden som kan vara intressanta föremål för restaurering, men inventeringar krävs för att utvärdera analysmetoden.

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    Fulltext
  • 40.
    Flodin, Charlotte
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi.
    Equity in rural water resource development and management: A case study of Kilombero Valley, Tanzania, and the investments delivered by a participatory and demand-driven NGO2015Självständigt arbete på avancerad nivå (masterexamen), 30 poäng / 45 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The demand-driven and participatory approach to water resource development and management in Tanzania has been both praised and criticized; some see progress where others see increased inequalities. This study focuses on one progressive, demand-driven NGO which has a participatory approach to water resource development and management. This NGO, MSABI, is active in Kilombero Valley in southern Tanzania, and can be considered successful as it manages to keep 91 % of its water points functional, whilst the national average for pump functionality is just above 50 %.

    To study the performance of MSABI from a user perspective, it was decided that two sites in Kilombero Valley should be investigated in terms of users’ views on water access and quality. The identification of sites is based on population density and landcover change, so that the issues of scale and urban bias, as well as changes in the landscape affecting hydrological processes, are accounted for. In total, 29 interviews were conducted (October to November 2014), 15 at the Ifakara study site, the more densely populated location, and 14 at the Mchombe Ward study site. The interviews were semi-structured, using a participatory approach, focusing on users’ perspectives on water sources and the access to and quality of those water sources in dry and rainy seasons. The information gathered was used to construct definitions for water access and quality. These definitions, as well as the two locations and categorization of participants according to socio-economic status, were then used to sort and analyse the collected material.

    The results show that MSABI does not manage to make water accessible in an equitable way because of its demand-driven and participatory approach to water resource development and management. However, MSABI offers the only improved water source at the Mchombe Ward study site, except for one improved open well. MSABI manages to counter urban-bias better than any of the other water resource development and management facilitators encountered at the two study sites. The seasons influence water access, especially at the more peripheral locations, where improved water sources are less common and, as open water sources, are more prone to drought and contamination. When participants in Ifakara seasonally migrate for farming, during 4-5 months per year, the majority’s access to improved water sources is lost. At the distant seasonal fields, open water sources are more common and few report that they treat the unsafe water. The migration to peripheral farmlands coincides with the rainy season, causing open water sources to have their lowest water quality when seasonal migrants utilize them. This underlines the importance of securing safe water supply for people at remote locations, and the important role MSABI plays as water resource developer at those locations.

    In conclusion, if the current demand-driven and participatory approach to water resource development and management is to be retained, regardless of the heavy criticism it has received with regards to equity, this study suggests that the practices of MSABI should be spread further based on MSABI’s ability to increase safe water access at remote locations. Another recommendation is to further look into the effects of seasonal migration on access to safe water. The effect seasonal migration has on water access in Kilombero could exist in other areas in Tanzania or in other countries. The aspect of seasonal migration might show that water access statistics are misleading, as the seasonal water consumption in remote locations risks being omitted in official statistics. 

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    fulltext
  • 41.
    Fones- Sundell, Melinda
    et al.
    Stockholms universitet, Stockholm Resilience Centre, Stockholm Environment Institute.
    Saywell, Darren
    Reporting back on Establishing water and food equity2012Ingår i: World Water Week in Stockholm, 2012: Water and food security: Overarching conclusions, Stockholm: Stockholm International Water Institute , 2012, s. 18-20Konferensbidrag (Övrigt vetenskapligt)
    Ladda ner fulltext (pdf)
    Fulltext
  • 42. Forsberg, Rene
    et al.
    Skourup, H
    Kenyon, S.C.
    Laxon, S.W.
    Jakobsson, Martin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för geologi och geokemi. Marin geovetenskap.
    New Arctic Gravity Field Grids with Applications for Oceanography and Bathymetry2007Ingår i: EOS Transactions: American Geophysical Union, v. 88(52), 2007, s. Abstract OS43A-0991Konferensbidrag (Övrigt vetenskapligt)
  • 43.
    Forselius, Ellen
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi och kvartärgeologi (INK).
    The Good, The Bad and The Seascape: Possible Effects of Climate Change in Tropical People and Ecosystems in the Western Indian Ocean Using a Gender Perspective2013Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The tropical seascape is herein defined as a landscape made up of five ecosystems: coastal terrestrial forests, mangrove forests, seagrass beds, coral reefs and the deep sea. Previous studies have shown that men and women use the tropical seascape in different ways. If the seascape was to change as a result of anthropogenic climate change, then men and women could potentially be affected differently by those changes. The seascape is particularly vulnerable to the predicted rise in sea-level and ocean warming, but the coastal terrestrial forests and mangrove forests are in addition vulnerable to the increased storms and hurricanes a warmer climate is predicted to lead to. While men and women utilizes these ecosystems in many different ways, this study found, based on the literature reviewed, that in a worst-case scenario all parts of the seascape could potentially be destroyed and none of the activities performed there today could be performed in the future. The deep sea would not be destroyed, but the fish living there would move to higher latitudes and deeper waters, effectively ending the fishing practices in the tropical waters. To save the tropical seascape anthropogenic climate change would have to stop on a global scale, since the problem cannot be solved on a local or regional level.

    Ladda ner fulltext (pdf)
    fulltext
  • 44.
    Galafassi, Diego
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Transformational knowledge practices in social-ecological systems2016Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Climate change and poverty alleviation are examples of interconnected challenges propelling changes across environmental, social, cultural and political spheres. Interconnected challenges are characterized by multiple causality, feedback loops, non-linear dynamics. Transformations, as fundamental reconfigurations of social-ecological relations, are increasingly proposed as a strategy for tackling interconnected challenges. Transformations seem to require a move towards diverse, integrated, imaginative, anticipatory, dynamic forms of knowledge making. Although new forms of knowledge creation are indeed emerging in sustainability science and practice, this area of studies is yet to yield a coherent research framework for analyzing the contribution of these practices to transformations in social-ecological systems. The central aim of this thesis is to a) provide a theoretical framework and b) to explore and assess feasibility and effectiveness of concrete knowledge practices that could help governance actors to move towards forms of deliberate transformations in the face of interconnected challenges. Two empirical research papers based on a case-study in Coastal Kenya are presented. In these papers we approached the interconnected challenges of social-ecological trade-offs by engaging multiple knowledge practices (ranging from dialogue, to narrative scenarios, participatory modelling and ecological modelling) to create a space for imagination and deliberation amongst governance actors and scientists. Assessment of this process was performed with a mixed methods research design, including interviews, surveys, and participant observation. Results suggest that overall, these knowledge practices supported: a) development of systemic and collaborative mindsets (Paper 1); b) revision of core assumptions (Paper 1); c) the identification of key cross-scale tradeoffs that were previously not considered by governance actors (Paper 2). These results highlight the potential of these knowledge practices in fostering knowledge relevant for re-imagination and reconfiguration of social-ecological systems. I conclude by proposing that transformational knowledge practices present at least four key elements in that they are: plural and coproduced, affect change across scales, involve multiple ways of knowing and foster imagination. 

    Ladda ner (pdf)
    popular summary
  • 45.
    Georges, Carolin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi och kvartärgeologi (INK).
    Dendroklimatologisk analys av lokalklimat vid Grövelsjön i Dalafjällen2013Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Climate on earth is getting warmer, which effects earth’s energy balance and so forth the ocean and atmospheric circulation.  In many sub-polar regions on the northern hemisphere changes due to warming of the climate can be observed. Some examples that already have been observed are shifts in tree line, towards higher altitudes and latitudes, increased ablation of Swedish glaciers and melting of the permafrost on the Siberian tundra. In Sweden climate change scenarios tell us that it will become warmer and that a higher amount of precipitation in form of rain will be an effect from this. To study climate changes in Sweden, transition zones are useful in order to observe changes in distribution of species and animal populations. This study uses tree rings from Scots Pine (Pinus sylvestris L.) that grow at the tree line in Grövelsjön that is part of the mountains in Dalarna County. By measuring the width of the tree rings, a chronology that is representative for July temperature is made over this area. The method is called dendroclimatology and has generally been used to reconstruct past climate for the last 1000 years.  The results of this study show that the tree ring chronology don’t show a clear increase in temperature for the last century, which could have been expected from an area like this. But the result also show that when instrumentally measured temperature were plotted month by month, the only month with significant up going trend in temperature in this area is April. A temperature change in April does not leave a signal in the tree rings because it is too cold for them to grow that early in the season.

    Ladda ner fulltext (pdf)
    fulltext
  • 46. Guo, Donglin
    et al.
    Wang, Huijun
    Romanovsky, Vladimir E.
    Haywood, Alan M.
    Pepin, Nick
    Salzmann, Ulrich
    Sun, Jianqi
    Yan, Qing
    Zhang, Zhongshi
    Li, Xiangyu
    Otto-Bliesner, Bette L.
    Feng, Ran
    Lohmann, Gerrit
    Stepanek, Christian
    Abe-Ouchi, Ayako
    Chan, Wing-Le
    Peltier, W. Richard
    Chandan, Deepak
    von der Heydt, Anna S.
    Contoux, Camille
    Chandler, Mark A.
    Tan, Ning
    Zhang, Qiong
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi. Stockholms universitet, Naturvetenskapliga fakulteten, Bolincentret för klimatforskning (tills m KTH & SMHI).
    Hunter, Stephen J.
    Kamae, Youichi
    Highly restricted near-surface permafrost extent during the mid-Pliocene warm period2023Ingår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 120, nr 36, artikel-id e2301954120Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Accurate understanding of permafrost dynamics is critical for evaluating and mitigating impacts that may arise as permafrost degrades in the future; however, existing projections have large uncertainties. Studies of how permafrost responded historically during Earth's past warm periods are helpful in exploring potential future permafrost behavior and to evaluate the uncertainty of future permafrost change projections. Here, we combine a surface frost index model with outputs from the second phase of the Pliocene Model Intercomparison Project to simulate the near-surface (similar to 3 to 4 m depth) permafrost state in the Northern Hemisphere during the mid-Pliocene warm period (mPWP, similar to 3.264 to 3.025 Ma). This period shares similarities with the projected future climate. Constrained by proxy-based surface air temperature records, our simulations demonstrate that near-surface permafrost was highly spatially restricted during the mPWP and was 93 +/- 3% smaller than the preindustrial extent. Near-surface permafrost was present only in the eastern Siberian uplands, Canadian high Arctic Archipelago, and northernmost Greenland. The simulations are similar to near-surface permafrost changes projected for the end of this century under the SSP5-8.5 scenario and provide a perspective on the potential permafrost behavior that may be expected in a warmer world.

  • 47.
    Halldén, Tom
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi och kvartärgeologi (INK).
    Förändringar i västra Yoldiahavets vattenmiljö under trettioett år: En studie av fossil från ostracoder, mollusker och foraminiferer från Myssjaren, östra Mellansverige2013Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    I denna studie undersöks hur vattenmiljön förändrades i ett område av västra Yoldiahavet, idag sjön Myssjaren i östra Mellansverige. Syftet med undersökningen har varit att återskapa hur vattnets salthalt förändrades i området genom att studera förekomsten av fossil från saltvattenkrävande bentisk kalkskalsfauna i lera från perioden.

    Fossil hittades från sju år, 10 395-10 388 lervarvsår BP, av den 31 år långa period, 10 410-10 379 lervarvsår BP, som har undersökts. Utifrån fossilförekomsten kunde det konstateras att vattnet var bräckt under dessa sju år. Eftersom att fossil inte hittades från tidigare och senare perioder Därför är det möjligt att vattnet var bräckt både före och efter denna period.

    Det som begränsade de undersökta arternas utbredning i området var halten suspenderat sediment i vattnet. Det var en konsekvens av att mycket sediment transporterades till området i och med att området befann sig mellan två större utlopp av glacialt smältvatten.

    Därför har denna studie, förutom att konstatera att vattnet var bräckt under den undersökta perioden, även visat en succession av arter i Yoldiahavet.

    I studien identifieras också en 4 år lång kallperiod som varade mellan 10 393-10 389 lervarvsår BP. Vid 10 387 lervarvsår BP börjar iskanten att avancera, troligen som ett resultat av denna kallperiod, vilket slutligen leder till att de undersökta arterna upphör att förekomma i leran.

    Ladda ner fulltext (pdf)
    Förändringar i västra Yoldiahavets vattenmiljö under trettioett år
  • 48.
    Halldén, Tom Halldén
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi.
    Measuring coastal erosion along the coast of Ystad municipality using PSInSAR and SBAS2017Självständigt arbete på avancerad nivå (masterexamen), 30 poäng / 45 hpStudentuppsats (Examensarbete)
    Abstract [en]

    In this study the use of two radar interferometry methods, PSInSAR and SBAS, were tested as tools for measuring coastal erosion. If successful it would have allowed for measuring coastal erosion as a function of material lost. The study area used was Ystad municipality, in southern Sweden.

    Radar data for the study was provided by the ESA, the European space agency, from their ERS-2 and ENVISAT satellites, spanning the period 1998-2005.

    Unfortunately, even after many different configurations of settings were tested, the results indicated that both methods are very unsuited for use in rural areas such as Ystad, whether for measuring coastal erosion or otherwise. Both methods had severe problems achieving significant coverage after low coherence areas were masked out, and PSInSAR suffered from several anomalies. This is likely due to the highly vegetated nature of the landscape, which results in low coherence through temporal decorrelation.

    Of the two methods SBAS showed the most promise, but not nearly enough to be considereduseful.

    It is, based on the scientific literature, possible that simpler interferometry methods might have been more useful. This, and other possible ways to improve the results is something that this study discusses at length.

    Ladda ner fulltext (pdf)
    fulltext
  • 49.
    Hamzo, Bachir
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi och kvartärgeologi (INK).
    Habitatmodellering som hjälpmedel i naturvårdsplanering: - exempel mindre flugsnappare (Ficedula parva)2010Självständigt arbete på avancerad nivå (magisterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Loss of biological diversity is today a major global concern. One of the main reasons for this is loss and fragmentation of species habitat due to changes caused by humans. Therefore it is important to consider the impact on biological diversity early in physical planning. This report uses a method that could assist the prediction of effects on biological diversity during stages of physical planning, such as environmental impact assessment (EIA) and strategic environmental assessment (SEA). By modeling in Geographic Information Systems (GIS) using logistic regression, connections between observations of Red-breasted Flycatcher (Ficedula parva) and various environmental variables where made. The aim was to establish the preferred habitat type for the Red-breasted Flycatcher and thereby help biodiversity consideration in physical planning and conservation. Connections were confirmed between the Red- breasted Flycatcher and the variables old deciduous forests and edge zones around water areas and wetlands. This most likely means that the species prefers old deciduous swamp forests. In order to get more conclusive results, better variable data as well as improved observations are required. The study shows that with the required improvements this method has potential to be a useful tool for conservation planing.

  • 50.
    Han, Guoyi
    Clark University, Graduate School of Geography.
    Understanding regional dynamics of vulnerability: a historical approach to the flood problem in China2011Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    Throughout its long history, China is among the world's most flood-prone and consequently the most experienced countries in coping with floods. This is a dissertation about developing a historical approach for understanding regional dynamic change of vulnerability to flood hazards in the Chinese context, and providing an analytic base for the country's shift of its flood management strategy from the current predominant and prevalent flood control approach to a broader and more comprehensive risk management paradigm. The dissertation asks two central questions: (1) How can the changing vulnerability situation be better understood and analyzed so that the insights gained are most relevant for policy and practice? (2) What are the plausible pathways and key options for managing future flood risks in China in the context of rapid socioeconomic transition and climate change? By developing an analytical framework and a case study in the Dongting Lake area of China, and by outlining three fundamental dilemmas and three plausible pathways for managing future flood risk in China, the dissertation concludes that China needs a new flood management strategy--one that centers on vulnerability reduction and resilience building and one that embraces and internalizes variability and uncertainty in decision making. While a resilience strategy embodies a wide range of opportunities for long-term sustainable flood risk prevention and mitigation, the dissertation argues further that China faces major dilemmas in managing its future flood risks. Trade-offs between economic development and flood vulnerability reduction and between cooperation and tensions across diverse actors and scales cannot be escaped.

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