Sökning: "sedimentation"

Visar resultat 16 - 20 av 209 avhandlingar innehållade ordet sedimentation.

  1. 16. Causes and consequences of Gonyostomum semen blooms

    Författare :Karla Münzner; Eva S. Lindström; Lars J. Tranvik; Gesa A. Weyhenmeyer; Silke Langenheder; Ann-Kristin Bergström; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Gonyostomum semen; algal blooms; brown water lakes; lake browning; iron; dissolved organic carbon DOC ; carbon cycling; pCO2; CO2; organic matter; sedimentation; Biology with specialization in Limnology; Biologi med inriktning mot limnologi;

    Sammanfattning : Aquatic ecosystems provide essential ecosystem services, but are also highly vulnerable to global change. Climate change, eutrophication and browning, for example, collectively drive the increase of harmful algal blooms in freshwaters. LÄS MER

  3. 17. Studies of an elusive element : processes that influence the net retention of mercury in lake sediments and peatlands

    Författare :Johan Rydberg; Richard Bindler; Carl Lamborg; Umeå universitet; []
    Nyckelord :Mercury; retention; lake sediments; peatlands; environmental archives; sedimentation; diagenesis; vegetation; permafrost; Environmental Science; miljövetenskap;

    Sammanfattning : Because of its toxic nature mercury is a threat to both wildlife and human health, and thus, it is an element of concern in the environment. Currently much of the mercury emitted to the atmosphere is derived from anthropogenic sources – both direct emissions and re-emission of already deposited anthropogenic mercury. LÄS MER

  4. 18. Cyanobacterial Nitrogen Fixation in the Baltic Sea : With focus on Aphanizomenon sp

    Författare :Jennie B. Svedén; Jakob Walve; Helle Ploug; Angela Wulff; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; cyanobacteria; Baltic Sea; nitrogen fixation; Aphanizomenon sp.; dissolved nitrogen; particulate nitrogen; sedimentation; Marine Ecology; marin ekologi;

    Sammanfattning : Cyanobacteria are widely distributed in marine, freshwater and terrestrial habitats. Some cyanobacterial genera can convert di-nitrogen gas (N2) to bioavailable ammonium, i.e. perform nitrogen (N) fixation, and are therefore of profound significance for N cycling. LÄS MER

  5. 19. Instability in Settling Fibres : A Numerical Study

    Författare :Feng Zhang; Anders A. Dahlkild; Fredrik Lundell; Mark Martinez; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; bre suspensions; sedimentation; instability; mixture model; point-particle mode;

    Sammanfattning : Sedimenting suspensions exist in a varity of natural phenomena and industrial applications. It is already observed in experiments that the dilute fibre suspensions experience a concentration instability under gravity at low Reynolds numbers. Initially well-mixed suspensions become inhomogeneous and anisotropic due to this instability. LÄS MER

  7. 20. Conservation Laws, Numerical Schemes and Control Strategies for Sedimentation and Wastewater Treatment

    Författare :Sebastian Farås; Matematik LTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Conservation law; Temple class system; numerical scheme; continuous sedimentation;

    Sammanfattning : A consistent theme throughout this thesis is quasilinear partial differential equations (PDEs) appearing in one-dimensional models of sedimentation for solid-liquid separation of suspensions. We mainly focus on continuous sedimentation in so-called clarifier-thickeners (CTs), which are found in mineral processing and wastewater treatment. LÄS MER