Miscellaneous - Sounds Wild
Riparian Corridor


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Riparian Corridor

Dappled sunlight filters through the dense vegetation bordering an Alaska stream. This streamside zone is known as the riparian corridor, and it's rich with life - songbirds nesting and singing, small mammals feeding and hiding, and moose and bears following stream side trails.

Riparian corridors include the streambank, floodplain, and distinct riparian vegetation transitioning into upland vegetation as the land rises away from the river. The width depends size of the river and the surrounding terrain and can vary from tens of feet to many miles, often encompassing side channels and wetlands. Riparian corridors are more productive than the surrounding lands due to the moisture and nutrients, and the abundance of vegetation and animal life. This benefits fish because these nutrients are the basis of the food chain. The riparian corridor moderates stream temperatures, filters sediments from surface runoff, slows flood waters, buffers storm runoff, and reduces peak flows during rainstorms.

Plant roots in the riparian help hold soil in place, like rebar strengthening concrete, and prevents or slows erosion of the river bank during high flows. Vegetation also adds roughness to the banks and floodplain, slowing water velocity during floods and reducing its power to erode. Slowing the flow of floodwater allows suspended sediments to settle out deposit silt and sand along floodplain, adding nutrients to the soil, and growing and strengthening the streambank.