Benthic Observatory

Funding of the HGF project MOSES will be employed to build a novel benthic observatory equipped with a moveable benthic chamber and is planned to be placed in previously mapped target areas, e.g. in eddy corridors to measure benthic respiration rates and other benthic fluxes (nitrate and iron) over a period of one year. This observatory will yield the worldwide first annual data set of in-situ benthic fluxes at >1000 m water depths. The flux measurements will be conducted at high temporal resolution to capture sedimentation pulses induced by bypassing eddies and other processes (e.g. dust storms, zooplankton blooms).

The O2 fluxes and accompanying geochemical data will be employed to calculate rain rates of organic matter to the seabed. This observatory will be augmented by a second lander carrying a sediment trap, a stereographic photo system, an upward looking ADCP (300 kHz) and a CTD equipped with O2 and fluorescence sensors. The observatories will be recovered during a short-term cruise taking place one year after the major two-leg expedition of the project.

The design of the lander system is not yet finalized since the construction of the observatory is currently still at development stage. The present design of the Biogeochemical Observatory (BIGO) for short-term (several days) in-situ measurements of benthic respiration rates and benthic fluxes in 2 benthic chambers can give an impression of how the observatory might look like (see image on the right).