Kelp_SDM_Physio_Supplementary

Le résumé fourni par la source

Large, forest-forming kelps are ecosystem engineers, dramatically influencing coastal ecosystems where they occur. Recent research has revealed that rafts of non-native kelps, including reproductively viable southern bull kelp (Durvillaea) and giant kelp (Macrocystis), are continuously arriving along Antarctica’s coastline. Environmental or biotic factors are presumed to act as current barriers to establishment. However, with warmer temperatures and reduced ice scour expected in the future, it is possible temperate / sub-Antarctic ‘ecosystem engineer’ kelp taxa will expand their range into the Antarctic. Here we conducted in vitro experimental studies on two kelp genera, Macrocystis (giant kelp) and Durvillaea (southern bull kelp), and correlative species distribution modelling, to assess their potential to establish in Antarctica. Both taxa exhibited reduced physiological performance after cold-exposure cycles, but also showed recovery potential, demonstrating resilience to extreme environmental stress. Both were also able to continue to release reproductive propagules. Models predicted that, with forecast warming, these kelps could potentially establish in parts of the Antarctic by the end of this century. Overall, high-latitude environments will become more suitable for the establishment of kelps as the climate changes. Our models also predicted a considerable loss of suitable habitat across current ranges of both taxa, where they have substantial ecological, cultural, and socioeconomic value. Indeed, localised extinctions have already been attributed to increasingly frequent heatwaves in these areas. Our findings provide important insights into the shifting distributions and thermal tolerance of these ecologically foundational kelps.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.