The influence of the degree of surface water pollution from the urban ecosystem Balti and Floresti on the planktonic algae

The study of the taxonomic structure of the planktonic algae and the chemical composition of the surface waters in the urban ecosystems of Bălţi and Floreşti, demonstrates the dependence of the diversity of the algoflora on the degree of water pollution and the amount of nutrients. It was determined that the difference in the number of species in the algoflora river Raut, upstream of the biological treatment plant (BTP) and downstream of the BTP, for both urban ecosystems (Balti and Floresti), is explained by the higher degree of water pollution downstream of the SEB. The diversity of algal flora in the studied aquatic objects differs greatly, thus, in the water of the Copaceanca tributary, in summer, 66 species of algae were identified, and in the water of the Flaminda and Dobrusa tributaries only 9 and 4 species, respectively, were identified. The floristic diversity and low frequency of algae flora in these two tributaries of the Raut river within the urban ecosystem is determined by the low concentration of nutrients, insufficient for the development of algae flora. According to the analysis, a greater diversity of algoflora is established in aquatic objects where the concentration of nutrients (N, P) attributes the quality of (III) – (IV) water, i.e. medium pollution.