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Overexploitation

Contents

Idea

Overexploitation, also called overharvesting, occurs when a renewable resource is exploited to the point of diminishing returns. Examples include wild plants, grazing pastures, fish stocks, forests and water aquifers. Sustained overexploitation can lead to the destruction of the resource. In particular, species may be driven to extinction.

Details

Scheffer writes that:

Consumption can lead to alternative attractors in a plant population (or more generally, exploited population). As more food is available, animals may respond numerically (by reproducing more) but also functionally (by eating more).

where the consumption can be modeled by the Monod equation,

cons=gAA+Hcons = g\frac{A}{A+H}

where gg food consumption and AA is food density, HH the half-saturation constant. Or the sigmoidal Hill equation for more intense consumption, pp is an integer and p1p \ge 1:

cons=gA pA p+H pcons = g\frac{A^p}{A^p+H^p}

References

  • Overexploitation, Wikipedia.

  • Marten Scheffer, Critical Transitions in Nature and Society, ch.2.2 and appendix A.3

category: ecology