A riparian zone or riparian area is the interface between land and a river or stream.Riparian is also the proper nomenclature for one of the fifteen terrestrial biomes of the earth.Plant habitats and communities along the river margins and banks are called riparian vegetation, characterized by hydrophilic plants.iparian zones may be natural or engineered for soil stabilization or restoration. These zones are important natural biofilters, protecting aquatic environments from excessive sedimentation, polluted surface runoff and erosion.