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Introduction How Rivers Run Stories Value Of A River What We Can Do
Flow of a River - Hydrology
Factors of flow: Inter-annual variability (pg 6 of 11)

The interplay of high and low flows is necessary to maintain a natural, functioning ecosystem. Floods are necessary to form floodplains, distribute rich alluvial soils, clear organic debris, sort coarse rock into an alternating pattern of bars and riffles, prevent the encroachment of streamside vegetation, recharge riverine wetlands and aquifers, and provide spawning areas to species such as northern pike.

During drought, very low flows can stress many forms of life in the short term. But they also allow seeds to sprout in normally inundated areas, helping to reinvigorate floodplain wetlands. Very low flows also help to consolidate alluvial soils.


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Introduction
Flow
Description
Water cycle
Watersheds
Stream order
Factors of flow
Consequences
Stories
Shape
Connections
Quality
Life
Summary
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