Essays about: "diatom"

Showing result 1 - 5 of 24 essays containing the word diatom.

  1. 1. Machine learning-assisted image analysis and metabarcoding for monitoring of plankton in the seas surrounding Sweden

    University essay from KTH/Industriell bioteknologi

    Author : Karin Garefelt; [2023]
    Keywords : Imaging FlowCytobot; imaging-in-flow cytometry; plankton imaging; convolutional neural network; metabarcoding; Imaging FlowCytobot; flödesmikroskopi; övervakning av plankton; konvolutionella neuronnät; DNA-streckkodning;

    Abstract : I miljöövervakningen av haven runt Sverige har manuell mikroskopi av plankton länge varit den huvudsakliga tekniken för att övervaka växtplanktonbestånden och algblomningar. Nya tekniker utvärderas, men det är inte känt hur resultaten från de nyare teknikerna relaterar till varandra. READ MORE

  3. 2. Mercury accumulation in lake sediments on different time scales – the influence of algal primary production

    University essay from Umeå universitet/Institutionen för ekologi, miljö och geovetenskap

    Author : Anne Rebotzke; [2023]
    Keywords : mercury; lake sediment; primary productivity; algal scavenging; biogenic silica; diatom proxy; chlorophyll-a; organic matter;

    Abstract : The aim of this work is to test the proposed approach of algal scavenging as a driver of sediment mercury (Hg) on different time scales and to gain a better understanding of the mechanisms of Hg accumulation in lake sediments. A 3000-year sediment record from Nylandssjön in northern Sweden was analysed for this purpose, as well as a 20-year sediment record from the seasonal sediment traps of this lake. READ MORE

  4. 3. Top - down control: parasitism and predation on Gonyostomum semen in Swedish brown water lakes

    University essay from Uppsala universitet/Institutionen för biologisk grundutbildning

    Author : Ingrid Bergman; [2022]
    Keywords : limnology; phytoplankton; top-down control;

    Abstract : Gonyostomum semen is a raphidophyte microalgae that can be found in brown water lakes all over Sweden. The species forms substantial summer blooms that can completely dominate the phytoplankton community, largely due to its limited grazing pressure. To test whether parasites control the abundance of G. READ MORE

  5. 4. Diatoms from the late Holocene of the western Chukchi Sea, Arctic Ocean: environmental signals and palaeoceanography

    University essay from Stockholms universitet/Institutionen för geologiska vetenskaper

    Author : Erik Browaldh; [2022]
    Keywords : diatoms; late holocene; SWERUS-L2-2-PC1; Herald Canyon; Chukchi Sea; ice-algae; sympagic; cryophilic; warm water diatom; Bering Sea Water species; bottom water temperature; BWT; benthic foraminifera; palaeothermometry; ice dynamics; Fragilariopsis; Fossula arctica; Paralia sulcata; Shionodiscus oestrupii; Thalassiosira simonsenii; Chaetoceros; Chaetoceros sp. 7;

    Abstract : The sediment Core SWERUS-L2-2-PC1 (2PC) retrieved from the Chukchi Sea, Arctic Ocean sits in an oceanographically dynamic location at the Arctic-Pacific Ocean gateway. The 8.3 m-long core was retrieved in Herald Canyon at the marginal ice zone at 57 m depth. READ MORE

  6. 5. Efficiency of diatom and flagellate-based marine food webs.

    University essay from Umeå universitet/Institutionen för ekologi, miljö och geovetenskap

    Author : Yasmina Hamladji; [2021]
    Keywords : phytoplankton; flagellate; diatoms; ciliates food web efficiency; fungi;

    Abstract : Aquatic microbial food webs are in general size structured. Phytoplankton, which constitute the base of the food web, are grazed by protozoa and mesozooplankton, which in turn are consumed by planktivorous fish. Food web efficiency (FWE) is a measure of how efficiently energy is transported up the food web. READ MORE