Ecological Quality of the Macroalgal Communities Along the Algerian West Coast (South Mediterranean Sea)

Macroalgae are important elements in coastal ecosystems. Their diversity and distribution are influenced by local ecological conditions, justifying their use in coastal ecosystem assessments. This study aimed to analyze the ecological status of macroalgal communities along the Algerian west coast. Four coastal departments (Mostaganem, Oran, Ain Temouchent and Ghazaouet) with ten sites were sampled in spring 2024. The results showed that there were 82 species of macroalgae grouped into 23 orders, 38 families, 56 genus and four classes: Floridaophyceae (47.56%), Phaeophyceae and Ulvophyceae (25.60%) and Chlorophyceae (1.21 %). The structural analysis revealed a clear dominance of Florideophyceae, with 39 species identified. The highest macroalgae diversity was found at the Ain Témouchent and Mostaganem sites, with 58 and 56 species, respectively. Statistical analyses revealed significant differences between stations, indicating a non-random species distribution influenced by environmental conditions. Management of macroalgae resources is needed to maintain the sustainability of the coastal ecosystem, through a national coastal monitoring program should be established.