Not lava, but muds and methane are emitted from the Arctic deep-water mud volcano Haakon Mosby. When it reaches the atmosphere, methane is an aggressive greenhouse gas, 25-times more potent than carbon dioxide. Fortunately, some specialised microorganisms feed on methane and thereby reduce emissions of this greenhouse gas. For the first time, a German-French research team showed which methane consuming microorganisms thrive in the ice-cold Arctic deep-sea. In an article in the journal Nature, the scientists also describe which environmental parameters control their activity - with a surprising result: High flow velocities of mud volcano water in the seafloor reduce the efficiency of the natural gas filter by 60%.

In 1990, the Haakon Mosby mud volcano was discovered by an international research team on the continental slope of the Barents Sea. The scientists chose its name in honour of the famous Norwegian oceanographer Haakon Mosby. The mud volcano covers an area of a about 1 square km and is located at a water depth of 1250 m. The centre emits muds, water and methane that rise from a depth of about 2 km below the mud volcano. Helge Niemann and Tina Lsekann from the Max Planck Institute for Marine Microbiology in Bremen, Germany investigated in their PhD thesis which methanotrophic microorganisms could thrive in the -1C cold Arctic deep-sea.

Haakon Mosby is a rather flat mud volcano rising only 10 m above the ocean floor. Visual inspection by the German and French researchers distinguished three distinct concentric ring-shaped zones: the centre, surrounded by a zone covered with sulphur bacteria and then the outer rim inhabited by tubeworms.

Although these habitats differ, methane is the primary food source for most microorganisms thriving in the ocean floor. At the surface of the centre, the scientists discovered formerly unknown bacteria that use oxygen to feed on methane. In sediment layers below the sulphur bacteria, Helge
'"/>

Contact: Dr. Helge Niemann
hniemann@mpi-bremen.de
49-421-202-8653
Max-Planck-Gesellschaft
19-Oct-2006