Lotic Riparian Complex

Description

This state includes the phase and plant community components believed to be the potential natural channel and incorporates the natural channel for the gradient and valley fill materials (E5) and fluvial surfaces that re freshened intermittently in order to produce the characteristic types of vegetation.
This stream type is suited to handle the energy, water, and sediments supplied by the watershed and promote the plant community components that provide stability to the system. If undisturbed, this phase can supply the highest benefits and services from the riparian complex including, but not limited to: diverse, resilient plant community components that can withstand high flow events; significant fish and wildlife habitat; resistance to invasive species invasions; highest potential water quality and quantity; and ground water recharge and release.
The natural disturbance regime within this state would have included beaver dam complexes which slowed stream flow rates, elevated water tables and reduced sediment loads; infrequent fires usually associated with periods of prolonged drought which, due to the fire tolerant nature of the plant species occupying these sites. Fire frequency would have been less on these sites as compared to the adjoining upland ecological sites due to increased fuel moisture associated with the greener vegetation; grazing by native herbivores which would have been attracted to these areas by the greener vegetation and reliable water supply, especially during periods of below normal precipitation or late summer months when upland vegetation is less palatable.

Submodel

Management interpretations

Description

This state represents a set of degraded channels (G5c - F5) that have crossed a threshold by becoming vertically and laterally unstable resulting in moderately deep entrenchment and loss of floodplain and floodplain step connectivity and vegetation. They are difficult, if not impossible to restore without changing profile, pattern, and dimension of the stream.
These channels have little value for wildlife, fish, and water quality unless residual pools are deep enough to remain inundated between recharge or storm events that restore stream flows and reconnect isolated pools.

Submodel

Description

This state includes channels that, after experiencing vertical and lateral instability and entrenchment, develop new floodplains within the entrenchment. Floodplain plant community components return to the incipient floodplains and streams develop new connectivity. Channel forming processes at bankfull are better able to handle the energy, flow, and sediments. Channels begin as B5c channels and with careful management, are able to develop E5 morphology with associated (although truncated) floodplains and terraces. Water tables are elevated and expand laterally. There is increased connectivity of upstream and downstream habitats resulting in improved fish and wildlife habitat and enhanced water quality.
Some streams that have had the riparian vegetation removed and/or significantly changed may not develop the native plant community components. Where Kentucky bluegrass (Poa pratensis) or other shallow rooted grasses have taken over as dominant on the floodplain marginal bank stabilization will occur.

Submodel