Key Species of Phytoplankton in Eastern Part of Segara Anakan Indonesia Based on Season

Abstract

Phytoplankton blooms are a problem that often occurs in estuarine and coastal ecosystems. Changes in phytoplankton community species composition, diversity, biomass, and distribution were caused by conditions of seasonal and temporal variation. The immediate location of the estuary ecosystem is near cities, rapid economic growth and human activity which tends to increase pressure on the environment there. The purposes of this research were to evaluate the seasonal and temporal variation and to determine the key species of phytoplankton in the eastern part of Segara Anakan which can cause a bloom based on season. The samples of phytoplankton were taken from 6 sites during April - September 2019 when the highest tide occurred during dry and rainy seasons. The community structure were performed using primer software Ver 5 to find the similarity and / or differences of community structure of phytoplankton based on season. Simper analysis was used to determine key species (phytoplankton species) based on season and location. The community structure of phytoplankton in Segara chicks were composed by 5 divisions. During dry season was dominated by 82% of Bacillariophyta, whereas during rainy season were dominated by Bacillariophyta (43%) and Chlorophyta (31%) and Cyanophyta (25%). This study shows that the phytoplankton community structure in this estuary presents environment conditions during the rainy season that increase the abundance of phytoplankton especially of that may thrive into blooms. The most key species was Oscillatoria limosa that had the highest percentage of contribution.

Keywords

• phytoplankton
• segara anakan
• spatial and temporal variation