Abundance and composition analysis of dinoflagellates in Mayangan and Binor Coastal Area, Probolinggo, East Java, Indonesia

Abstract

Dinoflagellates are one of the phytoplankton groups that an important role as primary producers in waters. However, in very abundant conditions (blooming) it can be dangerous for ecosystems and aquatic biota. This study aims to determine the composition and abundance of harmful dinoflagellates and environmental factors that influence the presence of dinoflagellates in coastal area of Mayangan and Binor, Probolinggo Regency, East Java. The method used in this study is a survey method by determining the sample point by purposive sampling. The research was conducted in March 2022. The result showed that the abundance of dinoflagellates in Mayangan waters 255 – 1511 cells/mL consisting of 10 genera namely Alexandrium, Ceratium, Dinophysis, Gambierdiscus, Glenodinium, Gymnodinium, Ostreopsis, Peridinium, Phyrodinium, and Prorocentrum. The abundance of dinoflagellates in Binor waters 716 – 2536 cells/mL consisting of 10 genera namely Alexandrium, Amphydinium, Bysmatrum, Cochlodinium, Gambierdiscus, Glenodinium, Gymnodinium, Peridinium, Protoperidinium, and Scrippsiella. The highest genus in Mayangan waters Ceratium 18% and Binor waters Protoperidinium 21%. The abundance of dinoflagellates in the Mayangan and Binor waters has no potential for blooming, but the presence of the dinoflagellate genus in the waters can still endanger coastal ecosystems because it can produce toxins. The presence of dinoflagellates is influenced by environmental factors such as salinity, nitrate, and phosphate.