Metodologia
The principles of Half-Earth are informed by biologist E.O. Wilson and ecologist Robert MacArthur’s theory of island biogeography, which builds on the first principles of population ecology and genetics to explain how distance and area combine to regulate the balance between immigration and extinction in island populations. The theory puts forth that a change in habitat area results in a change in the sustainable number of species by approximately the 4th root. As reserves grow in size, the diversity of life surviving within them also grows; as reserve area is reduced, the diversity within declines swiftly and to a mathematically predictable degree, often immediately and, for some endemic species, forever.
Quando 90 por cento de todo o habitat é removido, o número de espécies que podem persistir de forma sustentável diminui para cerca de metade. Esta é a condição actual de muitas das localidades mais ricas em espécies em todo o mundo. Nestes locais, se 10% do habitat natural restante fosse também removido, a maioria ou a totalidade das espécies residentes sobreviventes desapareceria.
Se, por outro lado, protegermos uma área suficiente, em certos locais a quantidade de espécies protegidas seria de 85% ou mais. Com cerca de metade da área da Terra protegida, a biodiversidade da Terra entra numa zona de protecção global.
The science of the Half-Earth Project aims to map and monitor biodiversity at a high-enough resolution to aid conservation decision-makers through our products, including the Half-Earth Project Map and the Species Protection Index (SPI) developed by the Map of Life at Yale University. Data sources include UNEP-WCMC, IUCN, and IPBES. The map is powered by the data storage, computational, and mapping capabilities of the Google Cloud Platform, Google Earth Engine, and Esri. Map of Life works in close collaboration with the GEO Biodiversity Observation Network (BON), E.O. Wilson Biodiversity Foundation, and in partnership with Google, Esri, NASA, the National Science Foundation, National Geographic, and other partners.
