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Introduction How Rivers Run Stories Value Of A River What We Can Do
Connections of a River - Connectivity
Longitudinal: River Continuum Concept (pg 2 of 9)

The River Continuum Concept-or "RCC" (Vannote et al., 1980)-illustrates longitudinal connectivity in greater complexity. Developed by a group of stream ecologists, RCC hypothesizes that streams exist in a continuous and fairly predictable pattern along their entire length. Streams have evolved in accordance with physical factors. The structure of the stream and its biological communities change along the length of the river. Organism functions change in response to food resources.

The headwaters of woodland streams (first through third orders) are shaded by overhanging trees. Little sunlight reaches water as an energy source to drive photosynthesis. Energy is instead derived from terrestrial organic matter, that is, leaves and woody material that fall into the stream.

Accordingly, many aquatic insects are species that can break down and digest terrestrial organic matter. If the stream is fed by springs, the water is cool and often supports trout. These headwater streams typically have a steeper gradient, with riffles, rapids, and falls.


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Introduction
Flow
Shape
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Description
Longitudinal
Lateral
Vertical
Temporal
Quality
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