Search for dissertations about: "kiselalger"

Showing result 1 - 5 of 13 swedish dissertations containing the word kiselalger.

  1. 1. Silicon cycling in the Baltic Sea : Trends and budget of dissolved silica

    Author : Liana Papush; Åsa Danielsson; Lars Rahm; Petra Tallberg; Linköpings universitet; []
    Keywords : Dissolved silica; trends; nutrient; nutrient ratios; diatoms; Redfield; limitation; eutrophication; riverine load; budget; fluxes; accumulation; retention; optimisation; Baltic Sea; Löst kisel; trender; näringsämne; näringsämnens kvoter; kiselalger; Redfield; tillväxtbegränsning; övergödning; flodtillförsel; budget; flöden; ackumulering; retention; optimering; Östersjön; NATURAL SCIENCES; NATURVETENSKAP;

    Abstract : The dissolved silicon (DSi) has a crucial role for growth of a large group of primary producers – diatoms and, hence, impact on functioning of the aquatic food web. This thesis contributes to an increased understanding of the modifications of the DSi cycling in the Baltic Sea. READ MORE

  2. 2. Tracing environmental change and human impact as recorded in sediments from coastal areas of the northwestern Baltic Proper

    Author : Lena Norbäck Ivarsson; Elinor Andrén; Thomas Andrén; Mikael Lönn; John Anderson; Södertörns högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Baltic Sea; paleoecology; diatom stratigraphy; stable nitrogen isotopes; hypoxia; nutrient discharge; eutrophication; Medieval Climate Anomaly; Little Ice Age; Environmental Studies; Miljövetenskapliga studier; Östersjö- och Östeuropaforskning; Baltic and East European studies;

    Abstract : The eutrophication of the Baltic Sea due to increased anthropogenic nutrient loads during the 20th century is well documented and studied. However, in the Baltic Sea drainage area, humans have affected the environment longer than the environmental monitoring can provide data for. READ MORE

  3. 3. Terrestrial Si dynamics in the Arctic: a study on biotic and abiotic controls

    Author : Hanna Alfredsson; Kvartärgeologi; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES;

    Abstract : Silicon is the next most abundant element in the Earth’s crust and its biogeochemical cycle is linked with that of carbon. Further, silicon is a beneficial nutrient for plants in terrestrial ecosystems and a key nutrient for diatoms in aquatic ecosystems. READ MORE

  4. 4. Marine silicon cycle through the Cenozoic

    Author : Guillaume Fontorbe; Kvartärgeologi; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Si isotopes; Paleogene; PETM; glacial-interglacial; ocean circulation;

    Abstract : Silicon (Si) cycle is one of Earth's major biogeochemical cycles. Furthermore, the dissolved form of Si (DSi) is an essential nutrient for both terrestrial and marine ecosystems. READ MORE

  5. 5. The novel sources of the neurotoxin BMAA in aquatic environments

    Author : Sandra Lage; Sara Jonasson Rydberg; Ulla Rasmussen; Ann-Sofi Rehnstam-Holm; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; β-N-methylamino-L-alanine; diatoms; dinoflagellates; shellfish; cockles; PST; växtfysiologi; Plant Physiology;

    Abstract : Neurotoxinet β -N-metylamino -L-alanin (BMAA) anses vara en potentiell miljöriskfaktor för utvecklingen av den neurodegenerativa sjukdomen amyotrofisk lateralskleros (ALS) och har en potentiell roll i flertalet andra neurodegenerativa sjukdomar. Sedan 2003, då det upptäcktes att BMAA produceras av den symbiotiska cyanobakterien Nostoc punctiforme  har flera andra BMAA producerande cyanobakteriearter identifierats. READ MORE