Meta-Analysis of Livelihood Impacts of Payments for Environmental Services Programmes in Developing Countries

Payments for environmental services (PES) programmes have been widely promoted over the last few decades in many developing countries. Improving the livelihoods of environmental services (ES) suppliers is not only seen as a side benefit but is often considered a prerequisite for the viability of PES. Yet, the ability to draw 'overview lessons' over the impacts of PES on livelihoods from literature review studies remains limited. To overcome these shortcomings, we undertake a meta-analysis of causal statistical studies on the effects of PES on the livelihoods of ES suppliers in the developing world. The set-up of our meta-analysis allows us to draw more conservative but more reliable and generalisable overview lessons. Our findings suggest that PES programmes are likely to have positive but modest livelihood impacts on ES suppliers. Further, several institutional characteristics of PES are found to be correlated with more favourable livelihood impacts, such as high payments, high degree of voluntary participation, low transaction costs and better access to alternative income sources. Lastly, our results highlight the importance of controlling for unobservable confounders when undertaking original evaluation studies on the impacts of PES. These factors should be incorporated in the design, implementation and evaluation of PES.