A taxonomy of value

So the first thing to do is to understand the types of value that may be associated with biodversity, a natural resource, or a natural feature. To keep the language from getting convoluted and awkward, I'll simply refer to ``resources,'' but you should remember that what follows applies to any aspect of the world that we might be interested in placing an economic value on.

• Use values are associated directly with the use of the resource, e.g., extraction of timber for sale or recreational use of a lake or pond.

• Non-use values are values not directly associated with the use of the resource. They come in (at least) three varieties:
  • Option value: The value associated with a resource because of its potential or future value, e.g., the possibility that a particular plant may contain a chemical that cures lung cancer.

  • Bequest value: The value associated with leaving a resource to future generations for their use or enjoyment.

  • Existence value: The value associated simply with knowing that a particular resource exists, even if you never have the ability to see it yourself, e.g., the Arctic National Wildlife Refuge for most of us.