Comparison of Phytoplankton Species Composition Between Open Water and Beneath Floating Macrophyte Mat in An Oxbow Lake of Central Kalimantan, Indonesia

Abstract

A total of 74 species of phytoplankton were found in Lake Lutan where beneath the floating macrophyte mat, IR was higher than at open water zone, OW. Euglenoids, Diatoms and Chlorophytes predominantly occurred. Density and biomass were higher at IR than OW, and chlorophyll-a was the opposite. Statistically, it was, however, no significantly different between OW and IR, even if the presence of macrophytes slightly attributed high diversity and abundance of phytoplankton in IR. Chlorophyll-a was detected higher in low than in high water period on both sites by 2-ways ANOVA. Chlorella sp1. was significant in density among abundant phytoplankton species by 3-ways ANOVA and MCA. CCA revealed water level fluctuation greatly influenced other physico-chemical factors, and by constraining physico-chemical parameters, dissolved oxygen, water level and temperature were significantly correlated with some abundant species of phytoplankton at OW and IR sites of Lake Lutan.