Sökning: "small rodents"

Visar resultat 1 - 5 av 39 avhandlingar innehållade orden small rodents.

  1. 1. Effects of herbivory on arctic and alpine vegetation

    Författare :Åsa Lindgren; Ove Eriksson; Jon Moen; Anders Angerbjörn; Ingibjörg S Jónsdóttir; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; herbivory; reindeer; rodents; functional traits; plant species composition; arctic; alpine; tundra; seed limitation; Carex bigelowii; Biology; Biologi; Plant Ecology; växtekologi;

    Sammanfattning : The distribution of plant species and functional traits in alpine and arctic environments are determined by abiotic conditions, but also by biotic interactions. In this thesis, I investigate interactions among plants and herbivory effects on plant community composition and plant functional traits in three different regions: Swedish Lapland, Beringia (USA/Russia) and Finnmark (Norway). LÄS MER

  2. 2. Spatial and temporal population dynamics in the mountain tundra – mesopredator and prey

    Författare :Rasmus Erlandsson; Anders Angerbjörn; Dennis Murray; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; population dynamics; cyclic; mountain tundra; arctic fox; Norwegian lemming; small rodents; mesopredator; predation; survival; reproduction; zoologisk ekologi; Animal Ecology;

    Sammanfattning : It is well known that competition, predation and fluctuating food resources can have strong effect on individual fitness and population dynamics. The complexity of natural systems can make it complicate to disentangle those processes, but environments with relatively simple food webs, and strong cyclic population dynamics offer contrasting conditions resembling experimental treatments. LÄS MER

  3. 3. The zoo-geomorphological impact of fossorial rodents in sub-polar alpine environments

    Författare :Bert Eriksson; Jan Boelhowers; John Östh; Hanna Ridefelt; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; zoo-geomorphology; fossorial rodents; sub-polar; alpine; geomorphic work; ecosystem engineers; Physical geography; Naturgeografi; Geography; Geografi;

    Sammanfattning : The geomorphological impact of small fossorial mammals (adapted to digging and living underground), such as rodents can be significant, and both their direct and indirect effects may contribute to landscape formation. This thesis is based on empirical field studies of two burrowing rodent species in sub-polar environments, namely invasive House mice (Mus musculus) on sub-Antarctic Marion Island and Norwegian lemmings (Lemmus lemmus) in sub-Arctic Abisko. LÄS MER

  4. 4. Odour guided predation on acorns by small rodents during direct seeding

    Författare :Mattias Engman; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

    Sammanfattning : Costs related to planting of seedlings and plant material is a major economic obstacle that may impede successful large-scale forest restoration. One way to reduce this cost is to use direct seeding instead of planting. Nut-bearing trees such as oaks have seeds with large nutrient storage that results in competitive seedlings. LÄS MER

  5. 5. Small-Scale Dosimetry for the Testis: Applications in Nuclear Medicine Diagnostics and Therapy

    Författare :Suaad Meerkhan; Lund Medicinsk strålningsfysik; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Testis; 111-In; Autoradiography; Biodistribution; Small-Scale; Monte Carlo; Dosimetry; spermatogonia; gammaH2AX; immunofluorescence;

    Sammanfattning : It is well known that the testicles are among the most radiosensitive tissue, and constitute an important critical target for both external and internal radiation during diagnostic and therapeutic use of radionuclides. In systemic radionuclide therapy where very high activities are administered, the testis may become a dose-limiting organ; often with a complex, non-uniform activity distribution and a resulting non-uniform absorbed-dose distribution. LÄS MER