The sediment-water interface in aquatic systems is an environment connecting bottom sediments with the overlying water column. This transition zone can be easily disturbed by mechanical mixing (bioturbation) caused by foraging fish and/or macroinvertebrates moving around and stirring sediment layers. The sediment of still water ecosystems is largely known as a reservoir of resting stages of various planktonic plants, including cyanobacteria (blue-green algae) and invertebrates. The ecological and evolutionary dynamics of cyanobacteria is in part a function of the numbers and ages of diapausing stages hatching from aquatic sediments. Successful recruitment from this "seed bank" must depend upon the resting stages being present at or near the sediment surface. Often, however, they are found as deep as 15 to 30 cm in the mud. Bioturbation may thus provide a mechanism for the regular return of buried cyanobacteria resting stages to the sediment surface.