Structure and seasonal distribution patterns of phytoplankton in a natural mountain pond of the Belezma biosphere reserve (Northern East Algeria)

The diversity of phytoplanktons serves as an ecological indicator for aquatic ecosystems due to their fast response to environmental changes. Relationship between phytoplankton distribution and 10 water physicochemical parameters was conducted in a natural pond of the Belezma biosphere reserve (Northern East of Algeria). Monthly sampling was conducted in three stations over 2 years between April 2017 and March 2019. The inventory comprising 72 samples identified 50 phytoplankton taxa from 6 phyla, 6 classes, 21 orders, and 31 families. The majority of water physicochemical parameters exhibited seasonal variability. Most of the taxa were of constant accuracy (58%); few were accessory (22%), while 10% were accidental and very accidental with five taxa each. The highest Shannon diversity index (H' = 2.70) was observed in spring 2018. The lowest value of H' (2.20) was noted in autumn 2018. The canonical correspondence analysis (CCA) showed that the abundance of phytoplankton varied with water temperature, turbidity, salinity, nitrates, and ammonium. Chlorophyceae, Dinophyceae, Zygnematophyceae, and Cyanophyceae were the most represented groups in summer, whereas Bacillariophyceae and Euglenophyceae were abundant within spring and autumn. These results enabled us to open new perspectives for the conservation and protection of the ecosystem “pond” in the protected area.