The German-Russian deep-sea expedition KuramBio (Kurile Kamchatka biodiversity studies) on board of the RV Sonne in 2012 following the footsteps of the legendary expeditions with RV Vityaz

摘要

The deep sea is the largest but least explored environment on Earth. The oceans occupy 71% of Earth's surface and 90% of this area is deep sea (Raupach et al., 2009; Ramirez-Llodra et al., 2010). Thus its inhabiting fauna represents the most typical life forms on the planet (Gage and Tyler, 1991). Recent investigations discovered a high biodiversity in the deep sea, preliminary estimates are ranging between 0.5 and 10 million species for the macrofauna (Brandt et al., 2004, 2007a, 2007b, 2007c; Grassle and Machiolek, 1992; Sanders and Hessler, 1969); estimates go as high as 20-30 million for the meiofauna (Adrianov, 2004). Global biodiversity has been estimated to hold 8.7 million species of which 2.2 million are marine (Mora et al., 2011). These authors extrapolate that 91% of species in the ocean still await description. Therefore, major aims of recent deep-sea investigations are still describe and explain patterns of benthic biodiversity in different deep-sea areas (Brandt et al., 2004; Sanders and Hessler, 1969). For example, for all waters surrounding Japan a total of 33,629 species have been reported (Fujikura et al., 2010). The CeDAMar expeditions in the framework of the Census of Marine Life documented that deep-sea biodiversity is very unevenly distributed in the different oceans and ocean basins (e.g. Ramirez-Llodra et al., 2010). Some mechanisms, however, were already identified that cause high local species concentrations (productivity and isolation) (e.g. Brandt et al., 2007b; Levin et al., 2001; Snelgrove and Smith, 2002).