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Watershed Planning within a Quantitative Scenario Analysis Framework
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Emergent stability in a large, free-flowing watershed
Ecology
|August 5, 2015
Summary
Free-flowing river networks act as natural portfolios, stabilizing ecosystems through diverse upstream conditions. Larger river catchments demonstrate greater stability in fisheries, water flow, and temperature.
Area of Science:
- Ecology
- Hydrology
- Fisheries Science
Background:
- Financial portfolios use diverse investments for stability.
- Natural systems, like river networks, may offer similar stability through integrated diversity.
Purpose of the Study:
- To test the hypothesis that free-flowing river networks function as natural portfolios.
- To examine if upstream geological, hydrological, and biological diversity confers ecosystem stability.
Main Methods:
- Compiled extensive fisheries, water flow, and temperature data from 142 sites.
- Analyzed data from 1980 to present within the Fraser River watershed, a large undammed river system.
Main Results:
- Larger river catchments exhibited more stable fisheries catches compared to smaller ones.
- Water flow and temperature were also more stable in larger catchments.
- Stability was found to be an emergent property of these river networks.
Conclusions:
- Free-flowing river networks act as hierarchically nested natural portfolios.
- These river systems enhance ecosystem stability by buffering against variation and extreme events.
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