The influence of the environment on the diversity of Euglena species and their abundance in the lagoon of Nador-Morocco

Abstract

The main objective of this work is to study the spatial and temporal evolution and distribution of Euglena species in the Nador lagoon. The study is based on four sampling stations and covers two specific seasons, namely spring and summer 2018. Euglenes belonging to the genus Euglena are particularly interesting and well known in the field of research, due to their great diversity in terms of pigmentation, size and morphological characteristics. Samples taken at each of the four sampling stations were carefully identified morphologically using an inverted light microscope. In total, five species belonging to the genus Euglena were identified, namely: Euglena viridis O.F. Müller 1786, Euglena Caudata Hübner 1886, Euglena Proxima P.A. Dangeard 1902, Euglena tuberculata Svirenko 1915, Euglena sp. Quantitative analysis of the species collected reveals some interesting results. The maximum cell density was recorded at station 4, located near the wastewater treatment plant, with a value of 55 cells per litre during the summer of 2019. In contrast, the minimum cell density was recorded at the same station 4, corresponding to Kariat Arekmen, with a value of 5 cells per litre during the spring period of 2019. These observations highlight significant variations in Euglenes cell density depending on geographical location and season.