Benthic macrofauna biodiversity on the East Coast of Algeria

This stu dy investigated the spatial and temporal variations in macrobenthic communities across three sites on the eastern coast of Algeria, El-Kala, Annaba, and Skikda, in 2021. These sites were selected to assess the impact of varying levels of human activity on marine biodiversity, with El-Kala experiencing minimal disturbance, while Annaba and Skikda were significantly affected by industrial and urban activities. Monthly sampling was conducted on both rocky and sandy substrates to capture a comprehensive picture of the biodiversity within these ecosystems. Water physicochemical parameters, including temperature, pH, salinity, and dissolved oxygen, were measured to evaluate the environmental conditions at each site. The results revealed a significant spatial variability in biodiversity among the sites. El-Kala exhibited the highest biodiversity, reflected in a Shannon-Wiener index of 2.51, followed by Annaba (2.06), and Skikda (1.89). Principal Component Analysis (PCA) was conducted to elucidate the relationships between the physicochemical parameters and ecological indices across the three sites. PCA revealed that higher salinity levels were strongly associated with Skikda, which was affected by industrial runoff. In contrast, temperature, dissolved oxygen, and pH were positively correlated with the ecological indices in El-Kala, indicating a healthier ecosystem with more stable environmental conditions. These findings highlight the urgent need for ongoing monitoring and conservation strategies to mitigate the adverse effects of anthropogenic activities on coastal marine ecosystems. This study highlights the critical importance of env i ronmental management in regions fac ing significant industrial pressure, such as Skikda, in preserving biodiversity and maintaining ecological balance.