VOLUME 13 (Supplement)

Phytoplankton composition and diversity in Lake Tikub, Tiaong, Quezon, Philippines

A study was conducted in Lake Tikub, Tiaong, Quezon, Philippines to determine its phytoplankton composition and diversity. Four abiotic parameters including chemical parameters (water pH, and dissolved oxygen) and physical parameters (surface water temperature and limit of visibility) were measured. Phytoplankton composition and diversity were assessed based on identification, cell counts and chlorophyll a determination. Trophic state index (TSI) was also computed based on the chlorophyll a content and Secchi Disk depth values. The lake was classified according to the traditional trophic state denomination based on the results for the computation of TSI. A total of 21 taxa, identified to the genus level, were observed in the euphotic zones of Lake Tikub which belonged to four major phytoplankton groups: diatoms, green algae, cyanobacteria and dinoflagellates. Among the 21 identified species, green algae were the richest group with 10 species, followed by diatoms (8 species) and cyanobacteria (2 species). Dinoflagellates had only one representative species. Diatoms and green algae were the most abundant phytoplankton groups in Lake Tikub. Algae are affected by physico-chemical parameters that could be the determining factor of their community structure in Lake Tikub. Trophic state index (TSI) of the lake in terms of water quality and chlorophyll a concentration showed a positive result classifying it as oligotrophic and mesoeutrophic. Based on the data gathered, the lake can sustain life, but further studies must be done to learn more about Tikub Lake.