Search for dissertations about: "Physical Geography"

Showing result 11 - 15 of 397 swedish dissertations containing the words Physical Geography.

  2. 11. Palaeoglaciology of the northeastern Tibetan Plateau

    Author : Jakob Heyman; Arjen P Stroeven; Clas Hättestrand; Helena Alexanderson; Frank Lehmkuhl; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Tibetan Plateau; palaeoglaciology; Physical geography; Naturgeografi; Quaternary geology; Kvartärgeologi; Physical Geography; naturgeografi;

    Abstract : This study concerns the palaeoglaciation of the northeastern Tibetan Plateau, with emphasis on the Bayan Har Shan (Shan = Mountain) in the headwaters of Huang He (Yellow River). To reconstruct past glacier development multiple techniques, including remote sensing, field investigations, cosmogenic exposure dating, and numerical modelling have been employed. READ MORE

  4. 12. Quantity and quality of soil organic matter in permafrost terrain

    Author : Gustaf Hugelius; Peter Kuhry; Philip Wookey; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; carbon; soil organic matter; soil organic carbon; permafrost; arctic; upscaling; peat plateau; cryoturbation; active layer; thermokarst; carbon nitrogen ratio; stable isotopes; humification; Physical geography; Naturgeografi; geografi med naturgeografisk inriktning; Physical Geography;

    Abstract : High latitude terrestrial ecosystems are considered key components in the global carbon (C) cycle and hold large reservoirs of soil organic carbon (SOC). Much of this is stored as soil organic matter (SOM) in permafrost soils and peat deposits and is vulnerable to remobilization under future global warming. READ MORE

  5. 13. Holocene climate and atmospheric circulation changes in northern Fennoscandia : Interpretations from lacustrine oxygen isotope records

    Author : Christina E. Jonsson; Gunhild Rosqvist; Jan Seibert; Philip Barker; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; oxygen isotope; diatom silica; lake sediment; atmospheric circulation; North Atlantic Oscillation; northern Fennoscandia; The Holocene; Little Ice Age; Physical geography; Naturgeografi; Physical Geography; naturgeografi;

    Abstract : This thesis investigates how variations in the oxygen isotopic composition of lake waters in northern Fennoscandia are recorded in lake sediment archives, especially diatoms, and how these variations can be used to infer past changes in climate and atmospheric circulation. Results from analyses of the oxygen isotopic composition of lake water samples (δ18Olakew) collected between 2001 and 2006 show that δ18O of northern Fennoscandian lakes is mainly controlled by the isotopic composition of the precipitation (δ18Op). READ MORE

  6. 14. More Water, Less Grass? : An assessment of resource degradation and stakeholders’ perceptions of environmental change in Ombuga Grassland, Northern Namibia

    Author : Patrik Klintenberg; Carl Christiansson; Wolter Arnberg; Peter Schlyter; Stein W. Bie; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Environmental monitoring; semi-arid; pastoralism; rural water supply; indicators; local knowledge; vegetation survey; satellite remote sensing; Physical geography; Naturgeografi; geografi med naturgeografisk inriktning; Physical Geography;

    Abstract : The objectives of this thesis are to assess: to what degree have natural resources deteriorated in a grazing area in northern Namibia, how do perceptions of environmental change held by local stakeholders there, correspond to scientific assessments, and how do these relate to national estimates? Analysis of the process of developing national indicators for monitoring of land degradation concluded that specific indicators should be developed on national level, and in some instances even on local level as there are no universal causes of land degradation. According to farmers overgrazing and low rainfall since the early 1990s cause negative environmental changes in the study area, partly confirming findings from national monitoring. READ MORE

  7. 15. Late Quaternary climate and environmental change in the summer rainfall region of South Africa : A study using trees and wetland peat cores as natural archives

    Author : Elin Norström; Karin Holmgren; Michael Meadows; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; paleoclimate; Late Quaternary; pollen; stable isotopes; diatoms; phytoliths; dendroclimatology; South Africa; Physical geography; Naturgeografi; Physical Geography; naturgeografi;

    Abstract : This thesis contributes with information on past climate and environmental changes in South Africa’s summer rainfall region. The study is based on multi-proxy analyses on wetland peat cores and analyses of stable isotope composition (δ13C, δ18O) and wood anatomy in cross sections from subtropical trees (Breonadia salicina). READ MORE