Marine sediments occupy about 70% of the Earth's surface and represent one of the most important interfaces in the Earth system because they regulate the transfer of carbon from the biosphere to the geosphere. A crucial control on carbon processing is exerted by the animals inhabiting the ocean floor, which extensively rework and oxygenate sediments while feeding and moving, a process referred to as bioturbation.
The significance of bioturbation was first realized by Charles Darwin, who devoted his final book to the subject. Recently, the second international meeting on bioturbation was organized in the Netherlands, following upon the success of the first meeting, in France (Marseille), in 2004. The purpose of this meeting was to provide a multidisciplinary update on the importance of bioturbation in sediment biogeochemistry, ecosystem functioning, and global biogeochemical cycles. Sixty scientists from 16 countries came together to address the physics, chemistry, geology, and biology of bioturbation in sediments and soils, in both the present and the past.