Search for dissertations about: "permafrost"

Showing result 21 - 25 of 69 swedish dissertations containing the word permafrost.

  2. 21. Spatial and Temporal Variations of Solifluction and Related Environmental Parameters in the Abisko Mountains, Northern Sweden

    Author : Hanna Ridefelt; Jan Boelhouwers; Antoni Lewkowicz; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; solifluction; movement rates; Abisko region; Geographical Information Systems; statistical modelling; geomorphic work; permafrost; Physical geography; Naturgeografi; naturgeografi; Physical Geography;

    Abstract : This thesis presents an assessment of the variation in solifluction occurrence, morphometry and movement rates in the Abisko region, northern Sweden. Variations in movement rates are analyzed both on a regional and local scale. READ MORE

  4. 22. The Torneträsk System - A basis for predicting future subarctic ecosystems

    Author : Didac Pascual; BECC: Biodiversity and Ecosystem services in a Changing Climate; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; climate change; carbon fluxes; ecosystem change; climate projections; rain on snow; modelling; impacts; snow; permafrost; winter warming events;

    Abstract : Arctic and subarctic areas have experienced a rapid warming and substantial increases in precipitation in recent decades. The frequency and intensity of some extreme events, such as fires, winter warming events, extreme rainfall, and droughts, has also increased. READ MORE

  5. 23. Iron in the Lena River basin, NE Russia : Insights from microscopy, spectroscopy and isotope analysis

    Author : Catherine Hirst; Carl-Magnus Mörth; Per Andersson; Mats Erik Åström; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; iron; reactivity; isotopes; permafrost; river; Arctic; Marine Geology; maringeologi;

    Abstract : Iron is an important mediator of biotic and abiotic processes on the Earth’s surface, being an electron acceptor in organic matter degradation, a surface for organic matter and trace element adsorption, and a required element for enzymatic processes during primary production. Yet, the role of iron as a mediator of carbon and trace element cycling in high latitude, permafrost-dominated regions remains poorly investigated. READ MORE

  6. 24. Studies of an elusive element : processes that influence the net retention of mercury in lake sediments and peatlands

    Author : Johan Rydberg; Richard Bindler; Carl Lamborg; Umeå universitet; []
    Keywords : Mercury; retention; lake sediments; peatlands; environmental archives; sedimentation; diagenesis; vegetation; permafrost; Environmental Science; miljövetenskap;

    Abstract : Because of its toxic nature mercury is a threat to both wildlife and human health, and thus, it is an element of concern in the environment. Currently much of the mercury emitted to the atmosphere is derived from anthropogenic sources – both direct emissions and re-emission of already deposited anthropogenic mercury. READ MORE

  7. 25. Temporal and spatial variability of carbon cycling in a subarctic landscape

    Author : Torbjörn Johansson; Institutionen för naturgeografi och ekosystemvetenskap; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Geologi; physical geography; Geology; Växtekologi; Plant ecology; Permafrost; Herbivory; Subarctic; Aerial photography; Vegetation change; Carbon balance; fysisk geografi;

    Abstract : This thesis deals with the carbon balance in a subarctic landscape at different temporal and spatial scales. Its focus is mainly on the peatland and mountain birch forest (Betula pubescens ssp. czerepanovii) ecosystems within the Abisko area in northernmost Sweden. This is an area with a temperature close to the 0 OC mean annual isotherm. READ MORE