Payments for environmental services (PES) programs incentivize landowners to protect or improve natural resources. Many conservationists fear that introducing compensation for actions previously offered voluntarily will reduce social capital (the institutions, relationships, attitudes, and values that govern human interactions), yet little rigorous research has investigated this concern. We examined the land cover management and communal social capital impacts of Mexico’s federal conservation payments program, which is a key example for other countries committed to reducing deforestation, protecting watersheds, and conserving biodiversity. We used a regression discontinuity (RD) methodology to identify causal program effects, comparing outcomes for PES participants and similar rejected applicants close to scoring cutoffs. We found that payments increased land cover management activities, such as patrolling for illegal activity, building fire breaks, controlling pests, or promoting soil conservation, by ∼50%. Importantly, increases in paid activities as a result of PES did not crowd out unpaid contributions to land management or other prosocial work. Community social capital increased by ∼8–9%, and household-level measures of trust were not affected by the program. These findings demonstrate that major environmental conditional cash transfer programs can support both land management and the attitudes and institutions underpinning prosocial behavior. Rigorous empirical research on this question can proceed only country by country because of methodological limitations, but will be an important line of inquiry as PES continues to expand worldwide.

支付环境服务（PES）计划会激励土地所有者保护或改善自然资源。许多保护主义者担心，对先前自愿采取的行动进行补偿会减少社会资本（控制人与人之间互动的制度，关系，态度和价值观），但很少有严谨的研究对此问题进行过调查。我们研究了墨西哥联邦保护支出计划的土地覆盖管理和公共社会资本影响，这是其他致力于减少森林砍伐，保护流域和保护生物多样性的国家的一个重要例子。我们使用回归不连续性（RD）方法来确定因果程序效果，比较PES参与者和接近得分截止点的类似被拒绝申请人的结果。我们发现，付款使土地覆盖物管理活动（例如巡逻非法活动，修建火灾，控制病虫害或促进水土保持）增加了约50％。重要的是，由于PES带来的有偿活动的增加并没有排除对土地管理或其他亲社会工作的无偿捐款。社区的社会资本增加了约8–9％，并且家庭一级的信任措施不受该计划的影响。这些发现表明，主要的环境有条件现金转移计划可以支持土地管理以及支持亲社会行为的态度和制度。由于方法上的限制，对此问题进行严格的实证研究只能逐个国家进行，但随着PES在全球范围内的不断扩展，它将成为重要的研究领域。