The composition and seasonal dynamics of planktonic green algae in the mouth of the kazanka river (Republic of tatarstan)

Abstract

© 2019, Dorma Journals. All rights reserved. The article presents the results of studies of the species composition and seasonal dynamics of planktonic green algae in the mouth of the Kazanka River in the city of Kazan in 2018. During the observation period, 51 taxa of green planktonic algae of Chlorophyceae and Trebouxiophyceae classes were found in the algoflora of the studied area, of which 53% of the species belong to the order Sphaeropleales spheroplei. The largest numbers of taxa belong to the families Hydrodictyaceae (13%), Scenedesmaceae (23%), Selenastraceae (10%), Chlorellaceae (14%), Oocystaceae (10%), Chlamydomonadaceae (8%). The total number and biomass range from 1.6-18.8 million cells/liter and 1.2-9.9 mg/liter. Flagellate monadic algae dominate in phytoplankton, belonging to the order Chlamydomonadales Phacotus lenticularis, Pandorina morum, Chlamydomonas sp. sp., Carteria sp. sp. The species of the spheroplei genera Scenedesmus, Pediastrum, Coelastrum, Crucigenia, Actinastrum, Dictyosphaerium, Oocystis. Mass reproduction of these algae throughout the summer and autumn indicates the extreme pollution of the waters in this part of the Kazanka River. Based on the data obtained, an assessment was made of the ecological state of water in the considered section of the river. Water quality is assessed as β-mesosaprobic (1.6-2.5) and moderately polluted; quality class III. According to trophic indices, the water in the considered area for the observation period is mostly consistent with the hypereutrophic type.