Aix Marseille University, Université de Toulon, CNRS, IRD, MIO (Mediterranean Institute of Oceanography), UM 110, 13288, Marseille, France.
Oceans Institute and School of Biological Sciences, University of Western Australia, Crawley, WA, Australia.
Sci Rep. 2023 Jun 29;13(1):10577. doi: 10.1038/s41598-023-37110-3.
The calcified red macroalga Lithophyllum byssoides, a very common midlittoral species in the western Mediterranean Sea, is a significant ecosystem engineer capable, under exposed and dim light conditions, of building wide and solid endemic bioconstructions near the mean sea level: the L. byssoides rims or 'trottoirs à L. byssoides'. Although the growth of the species is relatively rapid for a calcified alga, the construction of a large rim requires several centuries of near stable or slowly rising sea level. As the time scale of their formation is measured in centuries, L. byssoides bioconstructions constitute valuable and sensitive sea level markers. The health status of L. byssoides rims has been studied at two sites located far apart from each other (Marseille and Corsica), both in areas heavily impacted by humans and in areas with little impact (MPAs and unprotected areas). A health index is proposed: Lithophylum byssoides Rims Health Index. The main and inevitable threat is the rise in the sea level. This ecosystem would be the first case worldwide of marine ecosystem collapse resulting, indirectly, from man-induced global change.
钙化红藻 Lithophyllum byssoides 是地中海西部潮间带非常常见的物种，是一种重要的生态系统工程师，能够在暴露和暗淡的光照条件下，在接近平均海平面的地方建造宽阔而坚固的地方性生物构造：L. byssoides 边缘或“L. byssoides 步道”。尽管该物种的生长速度对于钙化藻类来说相对较快，但要建造一个大的边缘需要几百年的近稳定或缓慢上升的海平面。由于其形成的时间尺度以世纪为单位，L. byssoides 生物构造构成了有价值且敏感的海平面标志物。在马赛和科西嘉两个相距甚远的地点（马赛和科西嘉），对 L. byssoides 边缘的健康状况进行了研究，这些地点都受到人类的严重影响，也有一些几乎没有受到影响的地区（MPA 和未保护区）。提出了一个健康指数：Lithophylum byssoides 边缘健康指数。主要且不可避免的威胁是海平面上升。这将是全球范围内第一个由于人为引起的全球变化而导致海洋生态系统崩溃的案例。
