Do Payments for Environmental Services Affect Forest Cover? A Farm-Level Evaluation from Costa Rica
研究了哥斯达黎加一个长期环境服务付费项目对农场森林覆盖率的影响，发现参与项目使森林面积增加约11%到17%。
Payments for environmental services (PES) are popular despite little empirical evidence of their effectiveness. We estimate the impact of PES on forest cover in a region known for exemplary implementation of one of the best-known and longest-lived PES programs. Our evaluation design combines sampling that incorporates prematching, data from remote sensing and household surveys, and empirical methods that include partial identification with weak assumptions, difference-in-differences matching estimators, and tests of sensitivity to unobservable heterogeneity. PES in our study site increased participating farm forest cover by about 11% to 17% of the mean area under PES contract over eight years. <i></i>