The initial record of phytoplankton in Hon Lao islet of Cu Lao Cham World Biosphere Reserve, Quang Nam Province.

Abstract

The study was conducted to assess the phytoplankton biodiversity in Hon Lao Islet. The investigated sitesincluded streams and lakes located on the islet. We identified 126 phytoplankton species, belonging to 62 genera, 43 families, 27 orders, 11 classes, and 6 divisions, including Cyanobacteria, Ochrophyta,Bacillariophyta, Chlorophyta, Euglenophyta, and Dinophyta. Among these groups, Chlorophyta andBacillariophyta were the most dominant in terms of species. The average cell density on Hon Lao islet was 11,347 ± 4,149 cells/liter (mean ± SE) in the dry season and 3,355 ± 2,601 cells/liter in the rainy season, respectively. The dominant species that contributed to the studied area were different in both seasons, such as Oscillatoria princeps, O. limosa, Lyngbya martensiana, Anabaena inaequalis, Botryococcus braunii, Ulnaria ulna, Gomphonema parvulum, Fragilariasp., Iconella tenera, andPhacus orbicularis from the dryseason, and species of Oscillatoriasp.,Spirogyra ionia, Radiococcus polycoccus, Fragilariasp.,Eunotiapectinalis, E. minor,andNavicula cryptocephala from the rainy season.Analysis of the Bray-Curtissimilarity index showed that phytoplankton composition differed between monitoring sites.