Sökning: "tundra ecosystems"

Visar resultat 1 - 5 av 17 uppsatser innehållade orden tundra ecosystems.

  1. 1. Do OTC warming effects on ecosystem processes depend on moss species identity, precipitation, and moss removal?

    Master-uppsats, Umeå universitet/Institutionen för ekologi, miljö och geovetenskap

    Författare :Alexina Brännlund; [2023]
    Nyckelord :Experimental warming; Subarctic tundra mosses; Productivity; Ecosystem respiration; Decomposition;

    Sammanfattning : Long-term warming experiments in arctic tundra have resulted in reduced moss cover and increased vascular plant cover. As mosses have a major impact on microclimatic conditions, changes in community composition can potentially alter direct and indirect drivers of productivity and decomposition, which are low in arctic ecosystems. LÄS MER

  3. 2. Optimal foraging in an Arctic herbivore : How does the foraging behaviour of Svalbard reindeer (Rangifer tarandus platyrhynchus) respond to seasonal changes from summer through autumn of the Arctic tundra?

    Master-uppsats, Umeå universitet/Institutionen för ekologi, miljö och geovetenskap

    Författare :Emma Limosa Djurberg; [2023]
    Nyckelord :foraging behaviour; phenology; ungulate; Arctic; Rangifer tarandus platyrhynchus;

    Sammanfattning : Foraging decisions of large herbivores can be affected by many factors and have great effect on both above- and below-ground ecosystems. Here, I determine to which degree temporal (seasonality), or spatial (habitat) factors influence the foraging behaviour of Svalbard reindeer (Rangifer tarandus platyrhynchus) and asses if small-scale foraging behaviour correlates with an animals’ patch residence time. LÄS MER

  4. 3. Diversification of predators in multi-trophic communities: A trait-based theoretical approach

    Master-uppsats, Lunds universitet/Examensarbeten i bioinformatik

    Författare :Julio Antonio Ayala Lopez; [2022]
    Nyckelord :Biology and Life Sciences;

    Sammanfattning : One of the main challenges in ecology and evolutionary biology is to understand how biodiversity emerges and is maintained, given the complexity of ecological and evolutionary processes combined. Understanding how multi-trophic interactions occur from a theoretical perspective is highly relevant for our understanding of diversification in complex ecosystems. LÄS MER

  5. 4. Quantifying changes in soil bioporosity in subarctic soils after earthworm invasions

    Kandidat-uppsats,

    Författare :Joel Fransson Forsberg; [2021]
    Nyckelord :Biopores; macropores; geoengineering earthworms; X-ray tomography;

    Sammanfattning : Pores provide important hotspots for chemical and biological processes in soils. Earthworm burrows affect the macropore structure and their actions may create new preferential pathways for water and gas flow within soils. This, in turn, indirectly affect plants, nutrient cycling, hydraulic conductivity, gas exchange, and soil organisms. LÄS MER

  7. 5. Grazing Legacy Influence Nutrient Content and Dry Matter Digestibility of Five Reindeer Food Plants

    Master-uppsats, Umeå universitet/Institutionen för ekologi, miljö och geovetenskap

    Författare :Oleksiy Hronskiy; [2020]
    Nyckelord :Nutrient content; N and C; reindeer; grazing; HMGs; tundra ecosystems;

    Sammanfattning : Herbivores have a significant role in tundra ecosystem composition and processes. They can cause changes of vegetation composition and nutrient content that result in altered palatability of the vegetation and food availability for herbivores. LÄS MER