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University of Vienna
Department of Limnology and Bio-Oceanography
Althanstaße 14
1090 Vienna


Why should we care:

We know very little about the ocean and only a few percent of the worlds largest ecosystem have been investigated. Whether you live at the sea or not, we are all dependent on the oceans as regulator of global climate and as food source. See why we should care at the UN Ocean Atlas.

Microbes for beginners:

Microbial Oceanography -

What's it all about?

For the bare eyes they are usually invisible, but with the aid of microscopy and special staining techniques it is possible to visualize prokaryotes (bacteria and archaea) that are in the size range of around one micrometer.

Prokaryotes are ubiquitous and e.g. more than one million bacteria are counted in one cubic centimeter of seawater. Because the global ocean covers 71% of the earth's surface, prokaryotes are particularly numerous in this ecosystem. Thomas Reinthaler Due to their abundance and the capability to transfrom dissolved organic carbon into living biomass, and for example carbon dioxide, prokaryotes are an important biological component in the ocean.

We have some information on what jobs prokaryotes fulfill in nature, but we are at the very beginning to find out how they are doing it. The recent advance of molecular techniques allows to answer even more questions, e.g.: How many single species of bacteria or archaea are really out there? Are there groups of prokaryotes that share similar tasks?

As most of the cycling of organic matter is due to prokaryotes, a better understanding on their ecology in the ocean might help us to predict and decipher the changes in global climate on a biological basis.