Periphyton

Periphyton is a complex mixture of algae, cyanobacteria, heterotrophic microbes, and detritus that is attached to submerged surfaces in most aquatic ecosystems. It serves as an important food source for invertebrates, tadpoles, and some fish. It can also absorb contaminants, removing them from the water column and limiting their movement through the environment. The periphyton is also an important indicator of water quality; responses of this community to pollutants can be measured at a variety of scales representing physiological to community-level changes. So periphyton has often been used as an experimental system in, e.g., pollution-induced community tolerance studies.

Periphyton communities are used in aquaculture food production systems for the removal of solid and dissolved pollutants. Their performance in filtration is established and their application as aquacultural feed is being researched.

A risk for periphyton stems from urbanization. Increased turbidity levels associated with urban sprawl can smother periphyton causing its detachment from the rocks on which it lives. It can be important for the clearance of harmful chemicals and reducing turbidity.

Periphyton serves as an indicator of water quality because:

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