The Riparian Zone
Often referred to as a green ribbon of life along streams and rivers, the riparian zone is the transitional area of land that connects the aquatic (wet) ecosystem to the drier uplands that are not reached by flood waters. Due to the regular presence of water and periodic flooding, riparian areas support a great variety of plant and animal species. As a result, they are among the most productive and valuable of all landscapes, especially in arid climates.
Riparian areas represent less than 1% of Utah land, yet are the most important and heavily used wildlife habitat in the region. 82% of all bird species in the Intermountain West are dependent on riparian habitat.
Healthy riparian areas are vital to the health of stream ecosystems and the entire watershed as well. Many of the threats to our urban streams are directly related to physical changes to these areas and loss of vegetation. Riparian zones provide the following important benefits:
Erosion and Flood Protection
- Extensive root systems of riparian shrubs and trees stabilize streambank soils.
- Floodplains allow a stream system to store and absorb floodwaters, dissipating their destructive energy. High waters overflow out of the channel onto the floodplain.
- Vegetation slows down instream flows and helps to dissipate floodwater energy.
Water Quality Protection
- Plants slow runoff as it flows over the land, allowing pollutants to drop out before entering the stream.
- Root systems of riparian plants filter pollutants.
Food and Shelter
- Streams provide much needed wildlife corridors, especially in urban areas where habitat is highly fragmented.
- Multi-story layers of vegetation (trees, shrubs, ground layer) provide habitat and shelter for a diverse array of species. This structurally complex arrangement is often unique to stream corridors in arid lands.
- Tree shade helps to cool stream waters, which is critical for many aquatic species. Roots create stable overhanging banks, providing places for fish to hide and rest.
Naturally occurring riparian plants in Salt Lake County include grasses, sedges, willows, dogwood, wild rose, sumac, birch, maple, cottonwood, and much more.