Plankton Community Structure in Naruebodindrachinta Reservoir, Prachinburi Province

Abstract

This study aimed to analyze the structure of the plankton community in the Naruebodindrachinda Reservoir, Prachin Buri Province. Samples were collected from 9 stations in October 2021, January 2022, and May 2022. Phytoplankton samples were collected with a 20-micrometer net by filtering 10 liters of water, while zooplankton samples were collected using a 175-micrometer net dragged vertically for 5 meters. A total of 6 divisions and 44 genera of phytoplankton were found, including the division Chlorophyta (green algae) with 22 genera, Cyanophyta (blue-green algae) with 11 genera, Euglenophyta (euglenoids) with 3 genera, Pyrrhophyta (dinoflagellates) with 3 genera, Chrysophyta (chrysophytes) with 3 genera, and Bacillariophyta (diatoms) with 2 genera. The Chlorophyta division was the dominant group with the highest number of genera (22 genera), and an average density of 344,460–371,293 cells per liter. As for the zooplankton, 3 phyla and 5 groups were found: the phylum Arthropoda (Copepod, Cladocera, and Ostracod groups), the phylum Protozoa (Vorticella group), and the phylum Rotifera (Rotifer group). Cladocera was the dominant group, with an average density of 12,476–23,486 individuals per cubic meter. The diversity and density of plankton tended to vary with the seasons, reflecting the influence of changing environmental factors over time.