Interstitial microbial communities of coastal sediments are dominated by .

Microbial communities in subsurface coastal sediments are highly diverse and play an important role in nutrient cycling. While the major fraction of microorganisms in sandy sediments lives as epipsammon (attached to sand grains), only a small fraction thrives in the interstitial porewaters. So far, little is known about the composition of these free-living microbial communities.