Sökning: "nutrient ratios"

Visar resultat 1 - 5 av 27 avhandlingar innehållade orden nutrient ratios.

  1. 1. Silicon cycling in the Baltic Sea : Trends and budget of dissolved silica

    Författare :Liana Papush; Åsa Danielsson; Lars Rahm; Petra Tallberg; Linköpings universitet; []
    Nyckelord :Dissolved silica; trends; nutrient; nutrient ratios; diatoms; Redfield; limitation; eutrophication; riverine load; budget; fluxes; accumulation; retention; optimisation; Baltic Sea; Löst kisel; trender; näringsämne; näringsämnens kvoter; kiselalger; Redfield; tillväxtbegränsning; övergödning; flodtillförsel; budget; flöden; ackumulering; retention; optimering; Östersjön; NATURAL SCIENCES; NATURVETENSKAP;

    Sammanfattning : The dissolved silicon (DSi) has a crucial role for growth of a large group of primary producers – diatoms and, hence, impact on functioning of the aquatic food web. This thesis contributes to an increased understanding of the modifications of the DSi cycling in the Baltic Sea. LÄS MER

  3. 2. Closing nutrient cycles

    Författare :Usman Akram; Uno Wennergren; Karin Tonderski; Genevieve Metson; Bob Rees; Linköpings universitet; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

    Sammanfattning : Adequate and balanced crop nutrition – with nitrogen (N), phosphorus (P), and potassium (K) – is vital for sustainable crop production. Inadequate and imbalanced crop nutrition contributes to the crop yield gaps – a difference in actual and potential crop yield. LÄS MER

  4. 3. Nutrient Stoichiometry in Benthic Food Webs – Interactions Between Algae, Herbivores and Fish

    Författare :Antonia Liess; Peter Eklöv; Dag Hessen; Uppsala universitet; []
    Nyckelord :Ecology; ecologial stoichiometry; periphyton; grazer; benthos; trophic interactions; nutrient; algae; Ekologi;

    Sammanfattning : The aim of this thesis was to identify general structuring mechanisms in benthic food webs within the framework of ecological stoichiometry theory. Ecological stoichiometry is defined as the balance of multiple chemical substances in ecological interactions and explicitly considers the combined dynamics of key elements such as carbon (C), nitrogen (N) and phosphorus (P). LÄS MER

  5. 4. Nutrient limitation and elemental ratios in Baltic Sea plankton

    Författare :Jakob Walve; Karin Lochte; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Plankton; Östersjön; Ekosystem i vatten; Systems Ecology; systemekologi;

    Sammanfattning : Phytoplankton growth is frequently limited by the supply of nitrogen (N), phosphorus (P), or sometimes other elements. N2-fixing cyanobacteria are favoured by N limitation, which they may alleviate by adding new N to the ecosystem. LÄS MER

  7. 5. Biomass and Nutrient Status of Benthic Algae in Lakes

    Författare :Maria Kahlert; Alan Steinman; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Developmental biology; benthic algae; patchiness; C:N:P ratio; nutrient recycling; grazer; Utvecklingsbiologi; Developmental biology; Utvecklingsbiologi; limnologi; Limnology;

    Sammanfattning : For a complete picture of the lake ecosystem, it is necessary to understand the mechanisms regulating biomass and nutrient status (nutrient limitation, optimal supply, or surplus) of benthic algae, which are important primary producers and a food resource for grazers. This thesis gives an overview of the natural variation of benthic algae at different scales of space and time and on different substrates, and unravels some of the underlying factors. LÄS MER