6533b7d3fe1ef96bd126146c
RESEARCH PRODUCT
Diatom stratigraphy and long-term dissolved silica concentrations in the Baltic Sea
Timo TamminenKalle OlliAnnemarie ClarkeJuris AigarsDaniel J. ConleyÅSa Danielssonsubject
Dissolved silicabiologySedimentAquatic ScienceSpring bloomTest (biology)Oceanographybiology.organism_classificationOceanographyDiatomBaltic seaStratigraphyEutrophicationEcology Evolution Behavior and SystematicsGeologydescription
Abstract In many parts of the world coastal waters with anthropogenic eutrophication have experienced a gradual depletion of dissolved silica (DSi) stocks. This could put pressure on spring bloom diatom populations, e.g. by limiting the intensity of blooms or by causing shifts in species composition. In addition, eutrophication driven enhanced diatom growth is responsible for the redistribution of DSi from the water phase to the sediments, and changes in the growth conditions may be reflected in the sediment diatom stratigraphy. To test for changes in diatom communities we have analyzed four sediment cores from the Baltic Sea covering approximately the last 100 years. The sediment cores originate from the western Gulf of Finland, the Kattegat, the Baltic Proper and the Gulf of Riga. Three out of the four cores reveal only minor changes in composition of diatom assemblages, while the Gulf of Riga core contains major changes, occurring after the second World War. This area is set apart from the other Baltic Sea basins by a high frequency of low after spring bloom DSi concentrations (
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2008-10-01 |