ABSTRACT
Microalgae are the basis of life in aquatic ecosystems. As unicellular organisms, microalgae reproduce faster and can grow in extreme conditions. This study aims to reveal the diversity of freshwater microalgae found in the Jangkok River, Lombok, Indonesia. The research was conducted descriptively by determining the sampling station based on the different characteristics of the area through which the river flows. Sampling of microalgae was carried out in April 2022, three times for each station, with an interval of one week. The samples of microalgae were observed in the laboratory using a light microscope, while the identification process was carried out by referring to books and relevant journals. Data were analyzed descriptively by first determining the Shanon–Wiener (H’) diversity index; 48 genera and 85 species were found. The diversity of microalgae is at a high level with an index (H’) = 3.163. The genera with the most species were Nitzschia, Scenedesmus, Gomphonema, and Oscillatoria, while the most abundant species is Synedra ulna.
