Distribution of benthic macroinvertebrate communities in different kind of inland water bodies in northeastern Algeria.

Benthic macroinvertebrates are integral parts of inland waters, inhabiting a diversity of aquatic ecosystems where communities are spatially structured. Macroinvertebrates of some Mediterranean regions such as North Africa are still not well studied. Due this reason we proposed study the community structure in water bodies located in Northeastern Algeria. For this objective, we sampled 12 different kind of water bodies, two dams, three rivers, and seven streams during the period from October 2020 to September 2021. To biotic and abiotic data, a redundancy analysis (RDA) was applied with the aim of determine the role of both kind of variables for grouping the sites. Also, two types of Null models were considered: species co-occurrence and niche sharing for study the potential associations between species reported. Redundancy analysis showed that water velocity and conductivity were the main drivers of community structure of macroinvertebrates. The species co-occurrence results reveal that species associations are ramdom, except for two sites: El fadjoudj and Ain ben baida corresponding to Seybouse river. At the same time, there is no niche sharing and in consequence, there is no interspecific competition except in the two sites: Salah Salah Salah stream and Bouhamdane dam. The results revealed similarities with other similar studies for Algerian rivers and dams, and with other similar water bodies with Mediterranean climate.

Ecological structure of aquatic macroinvertebrate communities in the Hauts Plateaux of Northeast Algeria.

Aquatic macroinvertebrates are integral parts of functioning wetlands, inhabiting a diversity of aquatic ecosystems where communities are spatially structured. Macroinvertebrates of some Mediterranean regions such as North Africa are still not well studied. Here, we study the community structure of benthic macroinvertebrates in four different types of lotic and lentic wetlands in the semiarid Haut Plateaux of Northeast Algeria. Macroinvertebrates and 06 physicochemical parameters were sampled in 12 sites belonging to four types of habitats (lotic river, lentic river, dams, and sebkha [saline lentic water body]) during January-December 2021. Eventually, the character lentic-lotic was the most important variable affecting the affecting invertebrate communities in the Mediterranean region. The results revealed that sebkha and dams had a lower Shannon index than lentic and lotic rivers. Non-metric multidimensional scaling analysis showed a strong overlap between the community composition in lotic and lentic sites . Howeverin the three types of aquatic groups lentic river, dam and lotic habitats showed a strong overlap between the community whereas sebkha was markedly separated. Redundancy analysis showed that water velocity and pH, were the main drivers of community structure of macroinvertebrates, revealed a strong effect with pH (F1,8=4.15, P = 0.001) and water velocity (F1,8= 3.22, P = 0.002) , separating lotic communities from those that inhabited dams, lentic rivers, and sebkhas. As conclusion, this study contributes to the better understanding of the community structure of macroinvertebrates in semiarid North Africa where wetlands have been experiencing high anthropogenic disturbance.