Canopy-forming macroalgae, especially those belonging to the order Fucales, are creating the so-called brown algal forests that are considered amongst the most productive assemblages in the shallow coastal area. Moreover, they are biological indicators that are used for the assessment of the status of coastal belts according to important European Directives. Along Mediterranean rocky coasts they are disappearing quickly, Cystoseira species (sensu lato) in particular, and are gradually being replaced by turf-forming smaller and persistent algae, due to multiple anthropogenic pressures. The scope of this research was to verify changes in macrophyte structure and abundance, especially canopy-forming taxa, and the loss of Cystoseira s.l. species at two reference sites for macroalgae in the northern Adriatic Sea, during the period 2007–2019. At both sites, the decline of total Cystoseira s.l. spp. coverage (%) was substantial, both in the spring and autumn samples, while some rare and sensitive species were not found during the last surveys. The results of this study should help improving the conservation status of important canopy-forming species, focusing on the revitalisation of benthic critical habitats.

形成冠层的大型藻类，特别是属于富卡斯（Fucales）阶的大型藻类，正在创造所谓的褐藻林，被认为是浅海沿海地区生产力最高的组合之一。此外，它们是根据重要的欧洲指令用于评估沿海带状况的生物学指标。在地中海多岩石的海岸上，它们迅速消失，尤其是Cystoseira物种（Sensu lato），由于多种人为压力，它们逐渐被草皮形成的较小且持久的藻类所取代。这项研究的范围是验证大型植物结构和丰度的变化，尤其是冠层形成分类群的变化，以及半胱氨酸的损失。2007-2019年期间，在亚得里亚海北部的两个大型藻类参考点捕捞的物种。在两个站点上，总Cystoseira sl spp下降。在春季和秋季的样本中，其覆盖率都很高（％），而在上次调查中未发现一些稀有和敏感的物种。这项研究的结果应有助于改善重要的树冠形成物种的保护状况，着重于底栖关键生境的恢复。