Payments for ecosystem services in Mexico: Two decades of progress and challenges between research and practice

As some of the world's largest, longest lasting and most researched initiatives that reward individual and communal landowners for conserving forests and associated ecosystem services, Mexico's Payments for Ecosystem Services (PES) programmes provide a significant opportunity to examine questions of how, where, and by whom scholarship has been produced and the potential gaps revealed when comparing research insights with implementation patterns. To address these questions, we assembled the most up-to-date and comprehensive database of PES peer-reviewed publications and programme data in a single country. Our study includes a systematic analysis of relevant scientific literature in English and Spanish through 2022 (N = 140) and an assessment of the spatial and temporal distribution, timing, focus, and scope of all federally funded PES programmes at national, subnational, and local levels between 2003 and 2022. We find that variations in the spatial coverage of programme implementation have been associated with proportional levels of research interest over time and that studies represent multiple themes, spatiotemporal scales, and disciplinary and methodological approaches. With some variation, there is congruence among research findings that programmes have produced mostly positive ecological effects and mixed social effects. However, research has been disproportionately concentrated in specific geographic regions and Mexican scholarship has had considerably less global visibility and impact than European and U.S.-based research. By focusing our analysis on PES research and practice within a country-specific context and including literature produced in the local language, our analysis provides greater nuance than previous PES reviews regarding how knowledge is produced and by whom. We identify permanence of programme effects in Mexico as a key emerging issue for future research and, at a global scale, for the need to conduct such nuanced and inclusive assessments of other specific PES programmes to help identify and address key drivers of knowledge gaps in incentive-based environmental policies.