Sökning: "lake sediments"

Visar resultat 1 - 5 av 131 avhandlingar innehållade orden lake sediments.

  1. 1. Microcystis in lake sediments : its potential role in phosphorus exchange between sediment and lake water

    Författare :Anna-Kristina Brunberg; Uppsala universitet; []

    Sammanfattning : .... LÄS MER

  2. 2. Lake sediments around the Antarctic Peninsula : archives of climatic and environmental changes

    Författare :Rolf Zale; Umeå universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Lake sediments; Antarctic Peninsula; radiocarbon dating; climatic and environmental changes; sediment chemistry; naturgeografi; Physical Geography;

    Sammanfattning : Lakes and lake sediments from four areas around the Antarctic Peninsula are described.The concentrations of trace metals in sediment are found to be a useful tool in distinguishing between the different sedimentary phases during a transition from marine to limnic environment. LÄS MER

  3. 3. Boreal Lake Sediments as Sources and Sinks of Carbon

    Författare :Cristian Gudasz; Tranvik Lars; David Bastviken; Susan Ziegler; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; boreal lakes; allochthonous; lake sediments; sediment mineralization; bacterial production; bacterial biomass; carbon cycle; Freshwater ecology; Limnisk ekologi; Limnologi; Limnology;

    Sammanfattning : Inland waters process large amounts of organic carbon, contributing to CO2 and CH4 emissions, as well as storing organic carbon (OC) over geological timescales. Recently, it has been shown that the magnitude of these processes is of global significance. LÄS MER

  4. 4. Vegetation history, human impact and palaeogeography of West Estonia : Pollen analytical studies of lake and bog sediments

    Författare :Siim Veski; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; Earth sciences; Vegetation history; human impact; palaeogeography; shoreline displacement; The Baltic Sea; the Yoldia Sea; the Ancylus Lake; the Litorina Sea; pollen analysis; macro fossil analysis; bog and lake sediments; radiocarbon dating; Holocene; Estonia; Geovetenskap; Earth sciences; Geovetenskap; Earth Sciences with Specialization Environmental Analysis; geovetenskap med inriktning mot miljöanalys;

    Sammanfattning : The history of Holocene vegetation in western Estonia and the West Estonian Archipelago is described. Early Holocene sea level changes in the area are reconstructed, and human impact on the vegetation during the Late Holocene is discussed West Estonia was divided into five study areas (Rummu-Maardu, Mustjärve, Velise-Kiilaspere, Tôstamaa Peninsula, and northern Saaremaa in the West Estonian Archipelago, from north to south). LÄS MER

  5. 5. Acidification trends in Swedish lakes : an assessment of past water chemistry conditions using lake sediments

    Författare :Tom Korsman; Umeå universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Palaeolimnology; acidification history; alkalization; acid deposition; land-use; lake sediments; near infrared spectroscopy; diatoms; multivariate calibration; Sweden;

    Sammanfattning : This thesis presents temporal perspectives of lake acidification in Sweden. Sediment records have been used to study timing, trends and causes of acidification, and two different techniques for assessing past lake-water acidity are presented. LÄS MER