Photo-physiology and morphology reveal divergent warming responses in northern and southern hemisphere seagrasses

A better understanding of species and population responses to thermal stress is critical predict changes in their distribution under warming scenarios. Seagrasses are a unique group marine plants that play fundamental roles environments provide vital ecosystem services. Nevertheless, previous studies on seagrass tolerance have focused exclusively handful species, with the majority these remaining virtually unexplored. Moreover, date, no study has compared response between northern southern hemisphere seagrasses. Here, we conducted comparative mesocosm experiments using four from (i.e. Mediterranean: Posidonia oceanica, Cymodocea nodosa) Australia: australis Zostera muelleri) as representative two different life strategies, i.e. climax (P. P. australis) pioneer (C. nodosa, Z. muelleri). Plants acclimatized conditions at ambient temperature 26 °C) during 5-week period, were exposed simulated heatwave 32 for 2 weeks. Measurements plant responses, including photo-physiology, morphology, pigment content, performed end exposure. Results showed had significant effects photosynthetic performances seagrasses while negatively impacted counterparts. Similarly, favored growth plants, but strongly inhibited development species. Furthermore, photo-physiological content results suggested dealt than Our provides more insights into field ecology yields potential implication future conservation restoration activities.