River Partners' mission is to create wildlife habitat for the benefit of people and the environment.

  
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Riparian Ecology

River Partners would like to thank Meghan Gilbart who worked as a Fellow in 2009. Meghan developed the new Riparian Ecology section, including all of the drawings and much of the text.

The word riparian is derived from “ripa” in Latin which literally translates as a river bank.  The riparian zone is the interface between land and a stream.  Riparian habitat is formed from the diversity of plants that thrive in this dynamic interface where aquatic and terrestrial worlds interact.  Riparian habitat is extremely important to wildlife and public safety, yet the majority of this habitat type no longer exits.  River Partners works to rebuild this important vegetation through riparian restoration.  Restoration design requires an understanding of the physical river processes that determine plant growth, as well as the structure that is formed when certain plants are combined.  The creation of wildlife habitat and protection from flood damage are the driving forces behind River Partners’ restoration designs. These web pages were designed to outline the basic science behind riparian restoration.

Physical River Processes

Aerial Photo of Sacramento River Meandering Channel

Riparian plant communities are diverse, both in the number of species and in the structure (shape and size) of individual plants.  A large part of this diversity is due to the fact that the evolution of these plants has been influenced by physical river processes such as flooding, drought, sediment transport and channel meander.

 

Vegetation and Wildlife Habitat

Riparian brush rabbit

Riparian forests host a diversity of plant species, as well as a diversity of plant structures.  These forests provide multiple habitat features and resources for wildlife; in fact, riparian forests in California support a greater diversity of wildlife than any other habitat type (Smith 1980).  Riparian vegetation along river channels are also the primary migration routes used by wildlife, because these areas provide migrating animals with the food, water and cover required during their journey. River Partners considers the habitat needs of wildlife, including plant species and structural features, when designing restoration.

River Services

Recreation on Sacramento River

Riparian ecosystems support people as well as wildlife.  Rivers and their floodplains provide many “river services” to the surrounding local community.  Rivers deliver water throughout our region, and channels with healthy plant communities can improve the quality of out water supply.  Native plants on the floodplains can also lessen damage from large floods by trapping large debris.  Recreation along rivers like hunting, boating and fishing, is dependent on plant communities.  River services are enhanced by riparian restoration.

 

Vegetation and Levees

Sacramento River Levee

Riparian areas include the floodplain of a river that is periodically flooded and consequently has very rich soils.  Floodplains are frequently developed, especially as agricultural lands.  Flood control systems such as levees are typically constructed along rivers to protect developed floodplains.  Riparian vegetation that develops on the levees or in the floodway is often perceived as a threat to public safety.  Riparian vegetation within flood control systems can be designed to have no impact on the flood flows, but to positively improve the stability of the levees by limiting erosion and absorbing turbulence.  River Partners are able to improve public safety by restoring native plants in the floodways.

Vegetation in the Floodway

Flume

The floodway is a designated area for flood waters to flow through with mimimal impact to the surrounding landscape. Typically, the floodway is a levee-lined channel that has been designed by enigneers to carry a specific volume of water. Riparian vegetation growing within the levees is commonly believed to be a problem, because of fears that the vegetation will slow or re-direct the flows. Not all riparian plants behave equally when met with high velocity flows. Through experiments that study vegetation response to changes in velocity, and models of water velocities within the floodways, riparian vegetation within the floodways can be designed to have zero impact on flood flows.