Patterns of Bioturbation and Associated Matter Fluxes

Bioturbation, the biogenic particle and fluid transport in sediments, is generally thought to be important in the context of matter fluxes and therefore ecosystem functions. This chapter summarizes current knowledge on bioturbation in the Southern Baltic Sea, including locally very high solute exchange. An extended study based on chlorophyll as particle tracer indicates geographic differences in functional groups of particle reworking benthic infauna. This might enhance transient retention of organic matter in shallow water sediments of slope regions. Reworking also shows high local variability and surprisingly uniform overall rates throughout the region. The text states a lack of understanding as to how indices of bioturbation (BPC, BIP) reflect actual mechanistic functioning of animal-sediment-interactions. While displaying similar rates, bioturbation likely supports the integrity of processes occurring at and across the sediment-water interface.