Biodiversity promotes the stability of ecosystems

The diversity of species in an ecosystem can promote its stability. This is shown by a new international study published in the journal Science and involving Onofrio Mazzarisi, a young researcher from OGS and the Abdus Salam International Centre for Theoretical Physics - ICTP.

Does the stability of ecosystems depend on the presence of high biodiversity, or does diversity have the opposite effect and lead to instability? A group of researchers including OGS and the Abdus Salam International Centre for Theoretical Physics - ICTP, together with the Max Planck Institute for Mathematics in the Sciences (Germany), McGill University (Canada), the University of Kansas (USA), Université Paris Cité (France), PSL Research University (France) and Capital Fund Management (France) have made several contributions to this long-standing debate in ecology.

In the presence of a sufficient amount of resources, organisms belonging to the most diverse taxonomic groups reproduce exponentially, but as the environment becomes denser, growth reaches saturation: This dynamic is normally described by an S-shaped curve, whereas the researchers in the study used a model that predicts a more gradual dampening of the exponential growth phase than is normally assumed in this context. The key finding of the work is that this reproductive dynamic means that in an ecosystem where different species compete for existence, an increase in species diversity brings stability, contrary to some theoretical arguments previously proposed.