Sökning: "historical ecology"

Visar resultat 11 - 15 av 97 avhandlingar innehållade orden historical ecology.

  1. 11. Long-lasting ecological legacies of reindeer on tundra vegetation

    Författare :Dagmar D. Egelkraut; Johan Olofsson; Bruce Forbes; Hans Tømmervik; René van der Wal; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Alternative stable state; Herbivory; Historical contingency; Nutrient cycling; Plant-herbivore interactions; Plant-soil feedbacks; Rangifer tarandus; Reindeer herding; Traditional land use; Tundra vegetation;

    Sammanfattning : Reindeer can have strong effects on the plant species composition and functioning of tundra ecosystems, and often promote a transition towards a graminoid-dominated vegetation type. As a result, they influence many ecological processes, such as nutrient dynamics, soil biotic composition and functioning, and carbon storage. LÄS MER

  3. 12. Plant species diversity in semi-natural grasslands. Effects of scale, landscape structure and habitat history

    Författare :Triin Reitalu; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; habitat fragmentation; landscape diversity; habitat connectivity; historical maps; continuity; land-use history;

    Sammanfattning : The thesis examines the impact of present and past landscape structure, habitat history and management on different aspects of present-day plant species diversity in fragmented semi-natural grasslands in Sweden and in Estonia. Species diversity was significantly associated with present and/or past grassland connectivity in the majority of the studies in the thesis. LÄS MER

  4. 13. Cross-scale monitoring, landscape trajectories, and feedback in forest management : Examples from southern and middle boreal ecosystems in Sweden

    Författare :Sofia Eriksson; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Physical geography; Naturgeografi; Terrestrial ecology; Terrestisk ekologi;

    Sammanfattning : To manage for sustainability in a complex and changing world requires understanding of the coupled human-environmental system. The two case studies in this licentiate thesis are linked by what we can learn from past and current management in the form of feedback and how it can be incorporated into practical forest management within the boreal region. LÄS MER

  5. 14. Migration of Sea Turtles from Caribbean Costa Rica: Implications for Management

    Författare :Sebastian Troëng; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Animal ecology; conservation; predation; remigration; annual survival probability; mtDNA; satellite telemetry; tagging; Costa Rica; Tortuguero; endangered; migration; Djurekologi; sea turtles;

    Sammanfattning : Tortuguero National Park in Costa Rica hosts nesting by four species of highly migratory and endangered sea turtles (green, hawksbill, leatherback and loggerhead turtles). Sea turtle research at Tortuguero has been continuous since Dr. Archie Carr began studies in the 1950?s. LÄS MER

  7. 15. The role of vegetation dynamics in the control of atmospheric CO2 content

    Författare :Stephen Sitch; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Atmospheric CO2 content; climate change; plant functional types; terrestrial biosphere model; DGVM; vegetation dynamics; land use; land cover change; Plant ecology; Växtekologi;

    Sammanfattning : This thesis contains a description of the Lund-Potsdam-Jena Dynamic Global Vegetation Model (LPJ-DGVM) and its application to infer the role of vegetation dynamics on atmospheric CO2 content at different time-scales. The model combines vegetation dynamics and biogeochemistry in a modular framework. LÄS MER