Cyanobacteria diversity in Mesat River in Lubuklinggau City South Sumatra Province, Indonesia

Mesat River, where a lot of garbage dumps from upstream residents. This study aims to provide information about the diversity of cyanobacteria microalgae in the Mesat river. This type of research is survey research, conducted in February-April 2020. Microalgae samples were taken from 3 different stations following the river flow. Based on the identification and analysis, the Cyanobacteria found in the Mesat River in Lubuklinggau City consisted of 1 class, 3 orders, 4 families, 4 genera, and 5 species. The highest diversity value was at station 1 at 0.18 and the lowest was at station 3 at 0.14. The highest dominance value at station 1 is 0.001 and the lowest is at station 2 at 0.0003. The highest uniformity value at station 1 was 0.166 and the lowest at station 3 was 0.088. Measurement of the abiotic factors in the Mesat river consisted of: an average temperature of 26.87 °C, an average oxygen level of 45.63 mg/L, an average acidity of 6.6 and an average brightness of 17.56 cm. The conclusion of this study is the diversity of the distribution of cyanobacteria microalgae in the Mesat river, the city of Lubuklinggau, in the medium category.