U.S. Department of Agriculture: Forest Service -- National Agroforestry Center



Date of this Version

October 2003


Published by the Secretariat of the Convention on Biological Diversity. ISBN: 92-807-2389-8. Copyright © 2003, Secretariat of the Convention on Biological Diversity. Used by permission.


Biological diversity includes all plants, animals, microorganisms, the ecosystems of which they are part, and the diversity within species, between species, and of ecosystems. No single component of biodiversity (i.e., genes, species or ecosystems) is consistently a good indicator of the overall biodiversity as these components can vary independently. Functional diversity describes the variety of ecological functions of species or groups of species in an ecosystem. It is a biodiversity descriptor that provides an alternative way of understanding biological diversity, and the effects of disturbances caused by human activities, including climate change, on ecosystems.