A Novel Restoration Prioritization Approach to Save One of the Most Threatened Ecosystems on Earth
Strassburg, B. B. N., H. L. Beyer, R. Crouzeilles, A. Iribarrem, F. Barros, M. F. de Siqueira, A. Sánchez-Tapia, A. Balmford, J. B. B. Sansevero, P. H. S. Brancalion, E. N. Broadbent, R. L. Chazdon, A. O. Filho, T. A. Gardner, A. Gordon, A. Latawiec, R. Loyola, J. P. Metzger, M. Mills, H. P. Possingham, R. R. Rodrigues, C. A. d. M. Scaramuzza, F. R. Scarano, L. Tambosi, and M. Uriarte. 2019. Strategic approaches to restoring ecosystems can triple conservation gains and halve costs. Nature Ecology & Evolution 3:62-70.
There are critical areas in the world for conserving biodiversity – the so-called global hotspots for conservation priorities – which concentrate many unique species and are at higher levels of threat. Protecting the native vegetation remnants of these areas is essential, but not enough, to prevent a dramatic loss o biodiversity in the coming decades, as many native species persist as small and isolated populations that are now highly vulnerable to extinction. Expanding the area of native ecosystems and reconnecting isolated remnants through ecological restoration is fundamental to conserve biodiversity in such dramatic context, yet restoration is a difficult solution to implement.
Most areas targeted for restoration in the world are private landholdings, where farmers make their living by using the land for agriculture, cattle ranching and forestry. Replacing agro-pastoral land uses by native ecosystems can potentially be negative to farmers and local people, as well have high implementation costs, which challenge the potential to up-scale restoration in the areas with higher needs for it. Investments in restoration have to be maximized as much as possible, both in terms of the benefits and costs. As the benefits and costs of restoration are heterogeneously distributed across space, determining the priority areas for restoration is a critical challenge for research and practice.
This study used a novel restoration prioritization approach based on linear programming to identify priority areas for restoring the Brazilian Atlantic Forest, one of the top global conservation hotspots. Based on all 363 scenarios analyzed by combining different spatial configurations and outcomes for climate change mitigation, avoided extinctions and total costs, it was possible to identify a solution that , at the same time, avoids 26% of the biome’s current extinction debt of 2,864 plant and animal species (an increase of 257% compared with the baseline scenario), sequesters 1 billion tonnes of CO2-equivalent (a 105% increase), and reduces costs by US$28 billion (a 57% decrease). It was also possible to identify the impacts of economic and ecological efficiencies of scale on cost-effectiveness of restoration, which further helped to select a spatial configuration and restoration approach that maximize the benefits for carbon and biodiversity while reducing costs.
The methodological approach developed in this study may allow to optimize the limited resources available so far for ecological restoration by obtaining more benefits per unit of investment, thus making restoration more feasible and less demanding on land.
The PARTNERS Connection
The development of this complex study relied on the expertise of researchers with different skills and backgrounds, which were successfully grouped in collaboration of PARTNERS. The lead author and eight co-authors have a strong involvement in PARTNERS, and benefited from the networking of workshops to find the needed skills on the group for pushing this research forward.