Study of periphyton (algae flora) community in aquatic ecosystems of Guilan province

Periphytons are the most important microorganism communities which can be found almost in all aquatic systems. Periphytons play important roles in ecological functions of an ecosystem. They are composed of multilayered consortia of photoautotrophs (e.g. unicellular and filamentous cyanobacteria, benthic diatoms and green microalgae) and heterotrophs (bacteria, fungi and protozoa). Due to the role of periphytons in the processes of nitrogen fixation and dissolution of insoluble phosphorus and potassium, Samples of sediment, water and periphytons collected and investigated from three lagoons in Fashtam, Tazesel and Qalewersel in Guilan province. Results showed that Chlorophyta, Bacillariophyta and Cyanobacteria constituted 26.24%, 56.06% and 17.69% of the periphyton components in Qalewersel lagoon, respectively. In the Fashtam lagoon, the Chlorophyta, Charophyta, Euglenozoa, Ochrophyta, Bacillariophyta, and cyanobacteria species formed 38.48%, 20.58%, 1.72%, 1.74%, 19.68% and 19.52% of the periphyton components, respectively. Also, in the Tazesel lagoon, Chlorophyta, Euglenozoa, Bacillariophyta and Cyanobacteria constituted about 13.93%, 0.56%, 51.9% and 33.6% of components of periphyton, respectively.