What influences the implementation of natural climate solutions? A systematic map and review of the evidence

Abstract

Abstract Emergingresearch points to large greenhouse gas mitigation opportunities for activities that are focused on the preservation and maintenance of ecosystems, also known as natural climate solutions (NCS). Despite large quantifications of the potential biophysical and carbon benefits of these activities, these estimates hold large uncertainties and few capture the socio-economic bounds. Furthermore, the uptake of NCS remains slow and information on the enabling factors needed for successful implementation, co-benefits, and trade-offs of these activities remain underrepresented at scale. As such, we present a systematic review that synthesizes and maps the bottom-up evidence on the contextual factors that influence the implementation of NCS in the peer-reviewed literature. Drawing from a large global collection of (primarily case study-based, N = 211) research, this study (1) clarifies the definition of NCS, including in the context of nature-based solutions and other ecosystem-based approaches to addressing climate change; (2) provides an overview of the current state of literature, including research trends, opportunities, gaps, and biases; and (3) critically reflects on factors that may affect implementation in different geographies. We find that the content of the reviewed studies overwhelmingly focuses on tropical regions and activities in forest landscapes. We observe that implementation of NCS rely, not on one factor, but a suite of interlinked enabling factors. Specifically, engagement of indigenous peoples and local communities, performance-based finance, and technical assistance are important drivers of NCS implementation. While the broad categories of factors mentioned in the literature are similar across regions, the combination of factors and how and for whom they are taken up remains heterogeneous globally, and even within countries. Thus our results highlight the need to better understand what trends may be generalizable to inform best practices in policy discussions and where more nuance may be needed for interpreting research findings and applying them outside of their study contexts.