Great work by my former student, and now assistant professor Sandra Goff shows that people will contribute LESS to conserving nature if they are told that nature has a price.
http://www.sciencedirect.com/science/article/pii/S0921800916313672
Implication: Don’t put a price tag on natural systems that need protection. Sandra is now an assistant professor at Skidmore College in New York.
Timothy M. Waring 