Essays about: "sedimentkärnor"

Showing result 1 - 5 of 6 essays containing the word sedimentkärnor.

  1. 1. Holocene lake-level changes in the Siljan Lake District – Towards validation of von Post’s drainage scenario

    University essay from Lunds universitet/Geologiska institutionen

    Author : Savvas Paradeisis-Stathis; [2020]
    Keywords : Lake Siljan; Dalarna; basin isolation; catastrophic drainage; early Holocene; lake sediments; XRF scanning; C N ratio; magnetic susceptibility; pollen; Ancylus Lake; Earth and Environmental Sciences;

    Abstract : The Dalarna province in south-central Sweden shows a great variety of geological evidence from the Late Quaternary. A peculiar deglaciation pattern, along with unique hydrological conditions, has left a lot of space for speculations over the palaeoenvironmental conditions during the early Holocene. READ MORE

  3. 2. Methane flux in the Doñana wetlands : Waterbird guano addition and benthicinvertebrate effects

    University essay from

    Author : Noa Ratia; [2019]
    Keywords : aquatic invertebrates; bottom-up effects; CH4; Doñana; greenhouse gases; mesocosm; methane; sediment cores; akvatiska evertebrater; bottom-up effekter; CH4; Doñana; mesokosm; metan; sedimentkärnor; växthusgaser;

    Abstract : Wetlands are globally important biogeochemical hotspots, and their roles as either significant sources of greenhouse gas or carbon sinks are strongly controlled by environmental drivers such as carbon, nitrogen, and phosphorus availability, which can stimulate emission of three greenhouse gases: nitrous oxide (N2O), carbon dioxide (CO2) and methane (CH4). Mounting evidence suggests that aquatic invertebrate activity can enhance wetland greenhouse gas flux, through bioturbation and bioirrigation of surrounding sediments. READ MORE

  4. 3. Quaternary Arctic foraminiferal isotopes: species reliability and palaeoceanographic application

    University essay from Stockholms universitet/Institutionen för geologiska vetenskaper

    Author : Aron Varhelyi; [2018]
    Keywords : Palaeoceanography; Arctic; foraminifera; stable isotopes; Paleoceanografi; Arktis; foraminiferer; stabila isotoper;

    Abstract : To investigate whether foraminiferal stable isotope (δ18O/δ13C) variations have potential as a chronostratigraphic tool in the Arctic Ocean, this thesis presents new δ18O/δ13C data from five marine sediment cores. Three of those are downcore analyses (PS92/54-1; TC/PC-03; PC-07) and the remaining two are core top analyses (PC-04; PC-08). READ MORE

  5. 4. Using calcein-filled osmotic pumps to study the calcification response of benthic foraminifera to induced hypoxia under in situ conditions : an experimental approach

    University essay from Lunds universitet/Geologiska institutionen

    Author : Susanne Landgren; [2015]
    Keywords : benthic foraminifera; calcein; osmotic pump; hypoxia; Gullmar Fjord; bentiska foraminiferer; kalcein; osmotisk pump; syrebrist; Gullmarn; Earth and Environmental Sciences;

    Abstract : Bentiska foraminiferer används i stor utsträckning för miljöövervakning, t ex i kontext med syrebrist i kustnära vatten, vilket är det snabbast växande och mest allvarliga hotet mot marina ekosystem. Ett flertal studier har visat att många foraminiferarter har förmåga till överlevnad, förökning och biomineralisering under förhållanden med syrebrist (hypoxi) och till och med under helt syrefria förhållanden (anoxi). READ MORE

  6. 5. Exploring long-term trends in hypoxia (oxygen depletion) in Western Gotland Basin, the Baltic Sea

    University essay from Lunds universitet/Geologiska institutionen

    Author : Tianzhuo Liu; [2012]
    Keywords : Baltic Sea; hypoxia; lead analysis; lamination; mineral magnetism; loss on ignition; magnetotactic bacteria; Östersjön; hypoxi; bly analys; laminering; glödgningsförlust; magnetotactic bakterier; Earth and Environmental Sciences;

    Abstract : Övergödningen är ett av de största hoten mot Östersjöns miljö. Den orsakar inte bara algblomning under sommarhalvåret utan även syrebrist (hypoxi). Utbredningen av syrefria bottnar i Östersjön har ökat fyrfaldigt sedan 1960-talet till följd av ökade utsläpp av näringsämnen, så som fosfor och kväve. READ MORE