Résumé
We present here the raw data and scripts to reproduce the results presented in the preprint "Experimental approach to assessing the impact of the intensity of near-natural heatwaves on three marine phanerogam species in Mediterranean lagoon environment". Before using the scripts and associated data, we recommend reading the "readme" txt document.
Preprint abstract :
The increasing intensity, frequency, and duration of extreme climatic events (ECEs) due to climate change pose additional pressures on seagrass habitats in lagoon ecosystems. Among these ECE, this study focuses on the impact of marine heatwaves (MHWs) on seagrass species in Mediterranean coastal lagoons, i.e., the seagrasses Cymodocea nodosa, Nanozostera noltei, and Ruppia cirrhosa . Using a near-natural mesocosm, we simulated a 20 day MHW at three intensities (+2°C, +4°C, +6°C above control) during spring and summer, and assessed change in growth, respiration, and gross primary production. Species and seasonal responses varied markedly. C. nodosa showed enhanced net foliar growth in spring and stable growth in summer. N. noltei benefited from moderate warming in spring but was vulnerable to high intensity heatwaves in summer. R. cirrhosa was resilient in spring and exhibited increased growth in summer, particularly at +4°C. Hence, all three species were able to tolerate a single 20-day MHW with the species being increasingly better adapted in the following order N. noltei, R. cirrhosa, and C. nodosa. Increase of the initiation and growth of new leaves was a common phenological response observed in all three species, albeit at a lesser extent for R. cirrhosa. Our near-natural experimental approach reveals species- and season-dependent responses to MHWs, highlighting the complexity of seagrass resilience in lagoon ecosystems. These findings provide valuable insights to inform conservation strategies and improve the management of coastal habitats under future climate scenarios.