Sökning: "biogeochemical cycling"

Visar resultat 1 - 5 av 47 avhandlingar innehållade orden biogeochemical cycling.

  1. 1. Impacts and drivers of insect herbivory on element cycling in forests globally

    Författare :Bernice Hwang; MERGE: ModElling the Regional and Global Earth system; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; biogeochemical cycling; folivory; insect cadavers; insect frass; insect herbivory; litter decomposition; nutrient cycling; carbon; nitrogen; phosphorus; silicon; silica;

    Sammanfattning : The effects of insect herbivores on forest functioning are not well understood even though they can have important impacts on ecosystem processes by intercepting foliage before resorption and depositing nutrient-rich materials to the soil. In this thesis, I investigated the impact and drivers of insect folivores on carbon (C), nitrogen (N), phosphorus (P) and silica (Si) cycling in broadleaf forests, and how this varies with major climate variables. LÄS MER

  3. 2. Distribution and Biogeochemical Cycling of Arsenic In Grey and Brown Sand Aquifers in the Bengal Delta Plains (India)

    Författare :Devanita Ghosh; Joyanto Routh; Teresia Svensson; Punyasloke Bhadury; M. E. Donselaar; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Arsenic; aquifer; arsenite oxidation; aioA gene; Bengal delta plains; biogeochemical cycling biomarkers; DOC; SOC; Arsenik; akvifärer; arsenitoxiderande; aioA gene; Bengal delta plains; biogeokemiska omsättning; biomarkörer; DOC; SOC;

    Sammanfattning : An elevated level of Arsenic (As) in aquifers from India and Bangladesh affecting the human health has been widely reported since the late 1980s. The thesis aim is to investigate the present status of As contamination and biogeochemical cycling with direct role of diverse indigenous bacterial communities in As cycling in the Bengal Delta Plain (BDP) aquifers in Nadia district, West Bengal (India). LÄS MER

  4. 3. Direct and indirect pressures of climate change on nutrient and carbon cycling in northern forest ecosystems : Dynamic modelling for policy support

    Författare :Klas Lucander; BECC: Biodiversity and Ecosystem services in a Changing Climate; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Forest; boreal ecosystems; Forest biogeochemistry; Forest bioenergy; Boreal coniferous forest; base cations; Biogeochemical cycles; Dynamic Modelling; Carbon cycle; nitrogen cycle; decision support; policy-making; Weathering; Forestry; Land use change;

    Sammanfattning : Northern forest ecosystems play an important role in mitigating climate change by sequestrating carbon (C), while additionally providing and regulating other ecosystem services. A majority of the Swedish environmental quality objects (EQOs) that guide Swedish environmental policy and management are associated with the forest, and they have proven difficult to achieve. LÄS MER

  5. 4. Transport by Benthic Macrofauna: Functional Classification and Biogeochemical Response

    Författare :Stina Lindqvist; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Marine sediments; Early diagenesis; Bioturbation; Functional groups; Benthic fluxes; Imaging; Ecosystem function; Sediment reworking; Transport proxies; Fluorescent particles;

    Sammanfattning : Burrowing and reworking activities by benthic macrofauna regulate rates and pathways during organic matter mineralisation in bioturbated sediments. In so doing, they also affect the overall cycling of elements crucial in the biosphere (e.g. C, N, P, Fe, Mn and S). LÄS MER

  7. 5. Marine nitrogen fixation : Cyanobacterial nitrogen fixation and the fate of new nitrogen in the Baltic Sea

    Författare :Isabell Klawonn; Helle Ploug; Lasse Riemann; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; biogeochemistry; nitrogen cycling; nitrogen fixation; cyanobacteria; Baltic Sea; Marine Ecology; marin ekologi;

    Sammanfattning : Biogeochemical processes in the marine biosphere are important in global element cycling and greatly influence the gas composition of the Earth’s atmosphere. The nitrogen cycle is a key component of marine biogeochemical cycles. LÄS MER