Payment for Ecosystem Services (PES) programs are used as an approach to promote ecosystem conservation and restoration for hydrologic and other benefits. To quantify these benefits, we modeled the on-site (for rural landowners) and off-site benefits (for downstream water users relying on a large reservoir) of a pioneer municipal level PES project in Brazil established in 2005. We modeled the effects of landscape change on soil loss and sediment export from the Posses watershed using the InVEST model and a methodology that considered real aspects of the landscape and uncertainties in the input data and parameters, as well as economic factors. Results showed that a 3% increase in forest cover coupled with soil conservation practices led to a 0.9–3.5% and a 4.0–13.3% decrease in soil loss and sediment export, respectively. Part of this reduction was due to forest restoration and construction of micro-dams, which were built to improve infiltration close to unpaved roads. We show that PES projects enhance regulating services, providing benefits both onsite and to downstream reservoirs.

生态系统服务付款（PES）计划被用作促进生态系统保护和恢复以获取水文和其他利益的方法。为了量化这些收益，我们对2005年在巴西建立的先锋市政级PES项目的现场（针对农村土地所有者）和非现场收益（针对依赖大型水库的下游用水者）进行了建模。使用InVEST模型和一种方法来研究Posses流域水土流失和沉积物输出的景观变化，该方法应考虑景观的真实方面以及输入数据和参数以及经济因素中的不确定性。结果表明，森林覆盖率增加3％，再加上土壤保持措施，土壤流失和沉积物输出分别减少0.9-3.5％和4.0-13.3％。减少的部分原因是由于森林的恢复和微型水坝的建设，这些水坝的建立是为了改善未铺设道路附近的渗透。我们表明，PES项目可增强监管服务，为现场和下游水库带来收益。