Abstract: Balancing extreme poverty reduction with environmental conservation in rural LMICs requires credible causal evidence about which program designs deliver joint gains and when trade-offs arise. We conducted a systematic review of randomized controlled trials (RCTs) in rural, forested contexts, adopting a multi-outcome approach that includes poverty (income, assets, consumption, living conditions, labor, agricultural production) and conservation (forest cover/land-use change; biodiversity when available). Our search across multiple sources resulted in 112 RCT studies, with only 5 measuring both poverty and conservation results. Preliminary synthesis indicates: (i) on poverty, main gains concentrate in assets and income and were most common under monetary and mixed designs; non-monetary programs showed fewer short-run welfare effects. (ii) On conservation, significant positive effects were more frequently reported by non-monetary designs, especially training/extension and monitoring, primarily on forest presence; monetary and mixed designs yielded few significant conservation effects. (iii) Among the five dual-outcome RCTs, avoided-deforestation PES consistently delivered environmental wins with neutral short-run poverty effects; auction-based targeting improved environmental performance; intensive technical assistance paired with training achieved joint gains; unconditional liquidity raised deforestation risk; and production re-specialization (e.g., eco-tourism) showed localized environmental benefits with slower income responses. Cross-cutting design features such as conditionality, monitoring, targeting, and implementation intensity (e.g., ongoing TA), appeared to mediate impacts, and short evaluation horizons often limited detection of slower-moving welfare effects. This review develops a typology of intervention modalities and a preliminary mapping from design features to likely outcome patterns, while highlighting critical evidence gaps: few RCTs measuring both domains, limited biodiversity outcomes, and heterogeneous, context-dependent effects.
Bio: Adriana Molina-Garzón is an assistant professor at the Paul H. O’Neill School of Public and Environmental Affairs in Indianapolis. Her primary research interest is focused on understanding the conditions that hinder or promote sustainable development in rural areas, focusing on the role of nongovernmental agents in this process, including community-based arrangements, the role of NGOs and collaborations between these agents. Most of her work concentrates on climate change and environmental issues as a core area that affects vulnerable communities in rural areas and presents governance challenges at different scales, including international, national, subnational, and local levels. Her work concentrates on developing countries including several policies and programs in Central and South America, as well as Africa.
