What are ecosystem services worth?
Many ecosystem services are traditionally considered free to society. As public goods, their use and benefits are not exclusively controlled. For example, everyone enjoys the clean air, clean water, and flood control provided by healthy forest, range, and wetland ecosystems. Because these services are generally free, the true worth of healthy ecosystems is not recognized or accounted for in decision-making. In 1997, Robert Costanza and colleagues estimated the worldwide value of all ecosystem services at $33 trillion per year. While there were many uncertainties in developing this estimate and the calculation itself generated much criticism, this study is one of the first efforts to try to put a price tag on ecosystem services. In 2000, Forest Service economists estimated the minimum value of water from National Forest System lands to be $3.7 billion per year. Studies continue to evaluate the economic value of ecosystem services; at present, their true worth is unknown.
