UPCOMING EVENTS
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Erosion control
The tough, tangled roots of sedges, shrubs and trees provide structure to stream banks
and reduce soil loss to the stream.
Groundwater recharge
Riparian zones supply water to underground reservoirs. We call this process groundwater
recharge. Well vegetated areas trap the overland flow of water, allowing it to infiltrate
the soil and percolate downward. Underground stores provide the primary and sometimes
only source of water for streams during dry periods. Without this supply, the aquatic
ecosystem would collapse. Recharge is equally crucial for humans who depend on groundwater
for drinking and agriculture.
Filters
As surface runoff flows through the riparian zone to the stream, vegetation traps much of the sediment, reducing turbidity levels. Riparian vegetation also pulls nutrients out of the soil before they can reach the stream.
Flood control
Riparian zones serve as reservoirs for flood waters. The vegetation and soil absorb
overbank flow then releases it over time. This decreases the amount and energy of
water flowing through the stream at any one time. People who live in floodplains benefit
from the regulating effect of healthy upstream riparian zones.
Wildlife
Riparian zones concentrate water and nutrients from the stream and the surrounding
uplands. In response, the vegetation grows dense and structurally complex- it takes
on a variety ofshapes and sizes. This greater complexity translates into more niches
for organisms to fill.
- The diversity and production of riparian zones surpass all other terrestrial (land) ecosystems.
- Riparian zones in the Southwestern United States have a higher breeding diversity of birds than all other western habitats combined.
- Aquatic organisms are just as dependent upon riparian zones for their survival. The leaves, sticks and bark that fall into the water may provide up to 99% of the energy for organisms in a small headwater stream (the other 1% comes from photosynthesis).