The dynamic structure of phytoplankton community in Segara Anak Lake: a volcanic lake in Mount Rinjani National Park

Abstract

Segara Anak is a volcanic lake located in the Mount Rinjani National Park, West Nusa Tenggara, Indonesia. It covers an area of ± 11.3 km2 with a maximum depth of 230 m at 2010 m.a.s.l. Segara Anak one of tourism object around Rinjani Mountain. The purpose of this research was to study the phytoplankton community structure and physical and nutritional factors correlation in Segara Anak spatially and temporally. The sampling technique used was a purposive sampling method. The samples were taken at five stations with an increasing depth of 1 m, 5 m, and 10 m respectively. The sample collection was started from October to December 2017. The data were analyzed using One-way ANOVA, Kruskal Wallis, Cluster Analysis and Principal Component Analysis. We identified 19 phytoplankton genera with 4 classes. The phytoplankton structure, nutrient, and physical factors are significantly different in spatial depth and temporal sampling. The abundance of phytoplankton in Segara Anak is dominated by the Cyanophyceae class.