Hyporheic zone

The hyporheic zone is a region beneath and alongside a stream bed, where there is mixing of shallow groundwater and surface water. The flow dynamics and behavior in this zone (termed hyporheic flow or underflow) is recognized to be important for surface water/groundwater interactions, as well as fish spawning, among other processes.

The assemblage of organisms which inhabits this zone are called hyporheos.

The flow dynamics are controlled by the pressure variabilities arising on the stream-bed when the flowing water is diverted by the shape of the stream-bed created by benthic fauna, moving sediment and other obstacles. The mechanism of hyporheic flow can be triggered also by groundwater flow into the stream from the surrounding ground.

The term hyporheic was originally coined by Traian Orghidan^[1] in 1959 by combining two Greek words: hypo (below) and rheos (flow).

References

^ Orghidan, T. (1959). "Ein neuer Lebensraum des unterirdischen Wassers: Der hyporheische Biotop". Archiv für Hydrobilogie 55: 392–414.

External links

An article on the hyporheic zone of streams, and water purification. Includes a diagram.

The Hyporheic Network is a knowledge-transfer network on groundwater - surface water interactions and hyporheic zone processes. It provides a wealth of information and links to other resources on this topic.

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