In the fight against climate change, tree planting as a natural climate solution is a popular policy and land-use initiative among governmental and conservation organizations. Trees provide additional carbon stocks when planted in treeless agricultural lands. Yet there is another underutilized pathway to climate mitigation. Forests are the largest global above ground carbon sinks and managing them through forest-based agroforestry (FAF) can provide a myriad of benefits, a new study led by Yale School of the Environment scientists found.
"We want to make sure that we clarify that forest-based agroforestry (FAF) can achieve similar climate benefits as tree planting in fields," said Karam Sheban '28 PhD, '20 MF, who co-authored the study, which was published in Nature Climate Change. "The big takeaway is that human management of forests can result in better outcomes for forests, for people, and for the climate. It is not a zero-sum game."
Agroforestry is a management system that integrates trees with crops or pastures. Forest-based agroforestry, however, integrates crop production into existing forests. The study found that FAF can support forest health and biodiversity, enhance carbon sequestration and storage, generate economic benefits for local communities through sustainable harvesting of forest products (such as fruits, nuts, and medicinal plants), and aligns with Indigenous and traditional land stewardship practices.
Despite the benefits and the large number of people practicing forest-based agroforestry, it is receiving proportionally less support and funding than tree planting agroforestry initiatives by NGOs, private companies, and nonprofit agroforestry and conservation organizations. Two common misconceptions often account for the exclusion of FAF from policy language and funding opportunities, the authors said. The first is that industrial agroforestry systems that are designed around global commodity crops (such as cacao, coffee, and palm oil) are often conflated with traditional Indigenous approaches. The second misconception is that outcomes of industrial agroforestry in tropical forests can be extrapolated to temperate and boreal forest systems.
"There's a narrative that human activity in forests causes degradation, and that we really should leave forests untouched to maximize climate benefits. But humans living in and around forests have been supporting forest health for thousands of years and continue to do so now, " Sheban said.
The research team recommended explicit inclusion of FAF in agroforestry policies; designing policies that distinguish between sustainable FAF and harmful industrial agroforestry practices; and increasing research into diverse FAF systems across temperate and boreal regions to inform better policies and land management.
"For natural climate solutions involving trees, everyone is currently focused on removal of carbon from the atmosphere through tree planting. In the right place, this can be an effective strategy and the idea that removing a tree through forest management might be beneficial seems counter-intuitive to people, especially given how people develop attachments to individual trees," said study co-author Mark Bradford , the E.H. Harriman Professor of Soils and Ecosystem Ecology and faculty director of the Yale Applied Science Synthesis Program (YASSP). "Yet, forest management often necessitates removing some trees for the collective benefit of the forest. As people start to become aware of forest-based agriculture, we need to get that message out that effective forest management can achieve multiple services."
The study was also co-authored by Sara Kuebbing , lecturer and research director of YASSP and research scientist at the Yale Center for Natural Carbon Capture; Marlyse Duguid , the Thomas J. Siccama Senior Lecturer in Field Ecology and Yale Forests director of research; Mark Ashton , the Morris K. Jesup Professor of Silviculture and Forest Ecology and senior associate dean of The Forest School; Joseph Orefice , lecturer and director of forest and agricultural operations at Yale Forests; Alex C. McAlvay, of the New York Botanical Garden Center for Plants, People and Culture; and John Munsell, of Virginia Tech University College of Natural Resources and Environment.
