The economic value of biodiversity ...

A colleague asked me for information about the economic value of biodiversity.
I have done some internet research and here are some useful URL's that may provide useful starting points for further investigation.

SciDev.net
The Economic Value of Biodiversity: a scoping paper, Prof Jeff Bennett
Economics, Trade and Incentive Measures
On the Productive Value of Biodiversity, Jean-Paul Chavas
The value of Biodiversity: Insights from Ecology, Ethics and Economics,
The Value and Maintainance of Biodiversity
Biodiversity and Human health
Assigning Economic Value to Biodiversity
The Value of Biodiversity
Evaluating Restoration Alternatives
Ecologically informed values of Biodiversity for Conservation and Restoration
The Valuation of Biodiversity
PACIFIC: Samoa Puts Monetary Value on Natural Resources and Environment