Scientists from the University of the Witwatersrand in South Africa have produced a groundbreaking study that is changing our understanding of how to combat climate change through forest restoration. Their new research, published in Nature Communications, maps 195 million hectares globally where tree restoration will deliver maximum climate benefits without harming communities or ecosystemsThis area is roughly equivalent to the combined land area of South Africa, Namibia, Botswana and Zimbabwe.

What makes this study so important? Previous estimates of the total land available for afforestation projects were significantly higher, but often failed to take key factors into account. This new map presents 71 to 92 % decrease from previous numbersThe reason for this is the inclusion of layers that previous research did not have or ignored. For example, the study takes into account albedo effect, meaning that in some locations, tree regeneration may actually warm the Earth instead of cooling it by affecting how much sunlight is absorbed or reflected.

In addition, research excludes native grasslands and other ecosystems, where planting trees would damage biodiversity and worsen fire regimes. As Archibald from the Future Ecosystems for Africa (FEFA) programme at Wits University points out, previous studies often did not address the negative impacts of afforestation on biodiversity and human well-being, especially for poor people living in remote rural areas, which are often targeted by afforestation. Negative impacts are more likely when communities lack secure land rights and are heavily dependent on natural resources.

This distinction is particularly important for Africa. On the continent, natural grasslands and savannas are often inappropriately converted to forests, damaging biodiversity and exacerbating fire regimes. Although African countries contribute less than 5% of global carbon emissions, they face disproportionate climate impacts and have huge potential for nature-based solutions. The research directly supports the “Roadmap for Just Systems Transformations for Africa's People and Nature” initiative – a continent-wide collaboration between FEFA, Conservation International and partners, which aims to accelerate investment in natural climate solutions that benefit both mitigation and local livelihoods. Professor Forrest Fleischman, co-author of the study, stresses that policies must take into account land rights and the dependence of communities on natural resources, especially in countries where political rights are not respected. Archibald adds that “African scientists must now rise to the challenge and provide guidance on appropriate land management and restoration activities in non-forest ecosystems. This is the aim of the Africa Roadmap.”

Last but not least, this study serves as a timely reminder for policymakers ahead of the upcoming UN climate talks: Planting trees alone cannot solve climate change. Only restoring and protecting forests alongside aggressive decarbonization of industry can reforestation make meaningful progress toward safe climate limits. The study was co-funded by The Nature Conservancy and Oppenheimer Generations Research and Conservation under the FEFA program, whose mission is to prioritize Africa-informed solutions for ecosystem conservation.

This new mapping provides us with a realistic and substantial opportunity for reforestation that can truly contribute to meeting climate goals while protecting communities and ecosystems. It is a call for a smarter, more targeted and more equitable approach to restoring our planet. Spring

A study published in journal Nature Communications and drawing on 89 previous research projects