Biodiversité

Développement économique des territoires, Le Mag de l'aménagement, du logement et de la nature

via @CelineSacca Une présentation @CBN_Bailleul @Ecologie_Gouv du programme #CarHab en avant-première de la diffusion des données le 20 avril !

Les organismes vivants et la matière organique en décomposition libèrent dans l’atmosphère une grande diversité de composés organiques créant ainsi des paysages olfactifs servant de repères aux espèces au sein de leur milieu. Mais de nos jours, les activités humaines produisent elles-aussi d’innombrables composés odorants sans que nous n’y prenions nécessairement garde du fait de notre faible utilisation de l’odorat. Ces modifications anthropiques des paysages odorants affectent-elles le fonctionnement des écosystèmes ? Le cas échéant, comment est-il possible d’y remédier ?

Fragmentation of ecosystems leads to loss of biodiversity in the remaining habitat patches, but retaining connecting corridors can reduce these losses. Using long-term data from a large, replicated experiment, Damschen et al. show quantitatively how these losses are reduced. In their pine savanna system, corridors reduced the likelihood of plant extinction in patches by about 2% per year and increased the likelihood of patch colonization by about 5% per year. These benefits continued to accrue over the course of the 18-year experiment.

A ‘Blueprint’ to save critical ecosystems and stabilize the Earth’s climate.

More than two years in development, the Global Safety Net is the first comprehensive global-scale analysis of terrestrial areas essential for biodiversity and climate resilience, totaling 50.4% of the Earth's land. The report was published in Science Advances and highlights the importance of protecting and restoring the natural world to address three converging crises -- climate change, the loss of biodiversity, and the emergence of novel viruses such as COVID-19.

Expansive development for urbanization, agriculture, and resource extraction has resulted in much of the Earth’s vegetation existing as fragmented, isolated patches. Conservation planning typically deprioritizes small, isolated patches, as they are assumed to be of relatively little ecological value, instead focusing attention on conserving large, highly connected areas. Yet, our global analysis shows that, if we gave up on small patches of vegetation, we would stand to lose many species that are confined to those environments, and biodiversity would decline as a result. We should rethink the way we prioritize conservation to recognize the critical role that small, isolated patches play in conserving the world’s biodiversity. Restoring and reconnecting small isolated vegetation patches should be an immediate conservation priority.