Ignorer kommandoer på båndet
Gå til hovedindhold
Naviger op
Log på
> Forsiden > Natur og klima > Klimahistorie > Diatoms


Diatoms overview, Department of Quaternary geology

Stephanodiscus [alpinus/medius]

Research team

Stephanodiscus alpinus/medius ] - a freshwater diatom

Introduction Diatoms

Diatoms are microscopic unicellular algae, either circular (centric) or linear-elliptical (pennate) in shape. They are found in a wide range of aquatic habitats and exist in many forms including benthic (bottom living), epiphytic (attached) and planktonic (free living). Diatoms are common in the deep ocean, lagoons, estuaries, lakes and rivers.

Actinoptychus senarius Auliscus sp.1
Actinoptychus senarius and Auliscus sp.1 - two marine/brackish diatoms

The living diatom has a siliceous (made of silica) shell or frustule which can be found preserved in freshwater and marine sediments when the diatom cell settles out of the water column.

Cyclotella comensis
Cyclotella comensis - a freshwater diatom

Diatom species are extremely diverse in form and ecology and the community composition of diatoms found in aquatic systems is strongly influenced by environmental variables (e.g. water chemistry). In this way, a diatom assemblage preserved in sediments can provide a record of environmental change through time.

Diatomists in the department have interests in freshwater, coastal and marine environments and on seasonal, decadal, century and Holocene time-scales. Diatom projects include:

Other Websites

Emily Bradshaw - egb@geus.dk
Feel free to send e-mail for more information.

Edited by:
Niels E. Poulsen - nep@geus.dk