Alternative Equilibria in Shallow
نویسنده
چکیده
The turbidity of lakes is generally considered to be a smooth function of their nutrient status. However, recent results suggest that over a range of nutrient concentrations, shallow l&es can have two alternative equilibria: a clear state dominated by nquatic vegetation, and a turbid state characterized by high algal biomass. This bi-stability has important implications for the possibilities of restoring eutrophied shallow l&es. Nutrient reduction alone may have little impact on water clarity, but an ecosystem distur6ance lilie foodwe manipulation can bring the f&e bacf to a stable clear state. We discuss the reasons why alternative equilibria are theoretically expected in shallow lakes, review evidence from the field and evaluate recent applications of this insight in IaRe management.
منابع مشابه
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