Search for dissertations about: "Per Hall"

Showing result 1 - 5 of 18 swedish dissertations containing the words Per Hall.

  2. 1. Empirical Essays on Education and Social Insurance Policies

    Author : Caroline Hall; Per Johansson; Peter Fredriksson; Richard Blundell; Uppsala universitet; []
    Keywords : SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; Economics; Nationalekonomi; nationalekonomi; Economics;

    Abstract : This thesis consists of four self-contained essays. Essay 1: This paper evaluates the ef­fects of the introduction of a more comprehensive upper secondary school system in Swe­den in the 1990s. READ MORE

  4. 2. Role of manganese redox cycling for trace metals in the Baltic Sea

    Author : Susanne Bauer; Per Hall; Luleå tekniska universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Applied Geology; Tillämpad geologi;

    Abstract : Redox zones are defined by steep gradients of changing concentrations and changing redox potential. They form a transition zone between oxic and anoxic/sulfidic conditions, where nitrate, manganese and iron reduction occurs. These redox zones can be situated in the sediment as well as in the water column. In the Baltic Sea both types are found. READ MORE

  5. 3. Control factors of the marine nitrogen cycle : The role of meiofauna, macrofauna, oxygen and aggregates

    Author : Stefano Bonaglia; Patrick Crill; Volker Brüchert; Per Hall; Chritoph Humborg; Risgaard-Petersen Nils; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Nitrogen cycle; denitrification; DNRA; anammox; anoxia; hypoxia; eutrophication; meiofauna; macrofauna; aggregates; cyanobacteria; Baltic Sea; geokemi; Geochemistry;

    Abstract : The ocean is the most extended biome present on our planet. Recent decades have seen a dramatic increase in the number and gravity of threats impacting the ocean, including discharge of pollutants, cultural eutrophication and spread of alien species. READ MORE

  6. 4. Benthic fluxes of biogenic elements in the Baltic Sea : Influence of oxygen and macrofauna

    Author : Nils Ekeroth; Sven Blomqvist; Per OJ Hall; Bjørn Sundby; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Sediment biogeochemistry; Bioturbation; Benthic nutrient fluxes; Bottom water oxygenation; Box corer; Sediment sampling; Marine Ecology; marin ekologi;

    Abstract : This thesis investigates how benthic fluxes of phosphorus (P), nitrogen (N), and silicon (Si) change upon oxygenation of anoxic soft bottoms in the brackish, eutrophicated Baltic Sea. Direct measurements in situ by benthic landers demonstrated that fluxes of dissolved inorganic P (DIP) from anoxic bottom sediments in the Eastern Gotland Basin are higher than previously thought (Paper I). READ MORE

  7. 5. On benthic fluxes of phosphorus in the Baltic Sea proper – drivers and estimates

    Author : Nils Ekeroth; Sven Blomqvist; Per Hall; Volker Brüchert; Brita Sundelin; Jonas Gunnarsson; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Marine Ecology; marin ekologi;

    Abstract : This Thesis focuses on the exchange of phosphorus (P) across the sediment–water interface in the Baltic Sea proper, with particular attention to the influence of bioturbating macrofauna and benthic redox conditions. Benthic P fluxes have major influence on P availability in the water column, which in turn regulates growth conditions for dinitrogen fixating cyanobacteria in the Baltic proper. READ MORE