A Survey of Phytoplankton in Binosawan River and Mistika Creek, Rapu-Rapu Island, Albay, Bicol

Abstract

Phytoplankton have long been used as indicators of water quality, especially in disturbed areas. In the Philippines, freshwater ecosystems are seriously imperiled due to increasing developmental activities, as in the case of the mining activity in Rapu-Rapu Island, Albay. The study conducted a survey of the composition and abundance of phytoplankton vis-a-vis the two freshwater ecosystems, namely Binosawan River and Mistika Creek, in relation to prevailing water environmental conditions. Phytoplankton samples were collected through the bucket method using an improvised plankton net with 20 pm sieve size. Phytoplankton were identified and photographed under a compound microscope. Physico-chemical properties and heavy metal analysis of the water samples from the two freshwater ecosystems were also undertaken. Results showed that there were a total of fifteen (15) genera of phytoplankton in Binosawan River, and only four (4) genera in Mistika Creek. Diatoms like Fragilaria, Navicula, and Synedra, were the most abundant organisms in the two sites. Anabaena, Hormidium, Navicula, and Oscillatoria, possible indicators of heavy metal levels were identified. Physico-chemical properties of water and heavy metal analysis for Binosawan River and Mistika Creek were within the standards set for freshwater ecosystems.