Evaluation of Water Quality by Environmental Factors and Phytoplankton Community in the Yongjiang River, China

Abstract

Objective: Environmental factors were monitored annually at 13 sections in the Yongjiang river, Ningbo and China, the structures characteristics and the seasonal changes of the phytoplankton community from the sections were studied by using four different indexes. Methodology: The study showed there were 114 phytoplanktons species belonging to 6 phyla, 41 families and 80 genus. The phytoplankton community was dominated by the species of green algae and diatoms in the river. The 1st dominant species was Oscillatoria sp. and followed by Melosira sp. The peak of the abundance presented in spring in most cases. Results: There was a significant difference among the sections in phytoplankton community compositions and among the seasons at each section according , to the two-way ANOSIM similarity analysis. The combination of environmental factor, which affected the water quality mainly was CODCr TP and TN/TP. Conclusion: Both species diversity index and total pollution indexes in phytoplankton communities displayed that the Yongjiang river was polluted.