Areas of global importance for conserving terrestrial biodiversity, carbon and water

Recent research conducted by members of Nature Map consortium identifies which areas globally would provide the greatest benefits in jointly conserving biodiversity, carbon and water. To meet the ambitious objectives of biodiversity and climate conventions, the international community requires clarity on how these objectives can be operationalized spatially and how multiple targets can be pursued concurrently. To support goal setting and the implementation of international strategies and action plans, spatial guidance is needed to identify which land areas have the potential to generate the greatest synergies between conserving biodiversity and nature’s contributions to people. The article “Areas of global importance for conserving terrestrial biodiversity, carbon and water”, published in Nature Ecology & Evolution, compiles results from a joint optimization that minimizes the number of threatened species, maximizes carbon retention and water quality regulation, and ranks terrestrial conservation priorities globally.

Authors stress that selecting the top-ranked 30% and 50% of terrestrial land — that is, those areas with the highest priority— to achieve biodiversity conservation, storing soil and biomass carbon, and maintaining clean water quality regulation objectives simultaneously —would conserve respectively 60.7% and 85.3% of the estimated total carbon stock and 66% and 89.8% of all clean water, in addition to meeting conservation targets for 57.9% and 79% of all species considered.

The data and prioritization further suggest that adequately conserving all species considered (vertebrates and plants) would require giving conservation attention to ~70% of the terrestrial land surface. If priority was given to biodiversity only, managing 30% of optimally located land area for conservation may be sufficient to meet conservation targets for 81.3% of the terrestrial plant and vertebrate species considered. Results provide a global assessment of where land could be optimally managed for conservation. Discussion on how such a spatial prioritization framework can support the implementation of the biodiversity and climate conventions is addressed in this article.

Los resultados proporcionan una evaluación global sobre en qué lugares podría gestionarse la tierra de manera óptima para su conservación. La discusión planteada en el análisis es acerca de cómo un marco de priorización espacial de este tipo puede respaldar la implementación de los convenios sobre la diversidad biológica y el clima.

According to lead author Martin Jung, the research has collated best available data on the amount of suitable habitat for all terrestrial vertebrates, including all reptile species. As a first for global prioritizations, we also integrated distribution data of ~41% of known plant species, which changed global priorities.

The analysis carried out integrated currently best available data on above and below ground carbon and vulnerable soil carbon at risk from land-use change, and freshwater water regulation. These data were jointly prioritized together with biodiversity.

Results show how much land would be necessary to reduce species extinction risk under various assumptions, prioritising biodiversity only or together with carbon/water.  Ultimately, it was found that it would be needed about ~70% of terrestrial land area to conserve all species.

However, there are big gains possible with 10% or 30% of land in the right places. So, location really matters with regards to the range of possible species targets achieved, and carbon/water benefits can come at minimal extra cost if jointly optimized for with biodiversity.