The impact of environmental parameters on phytoplankton functional groups in northeastern China

Abstract

Phytoplankton is an important indicator of biological evaluation of water quality. However, the phytoplankton functional groups can better reflect the functions of aquatic ecosystems. The present study was carried out in the biggest tributary of Ussuri River of boundary between China and Russia. We totally identified 83 species of phytoplankton, which belonging to 17 functional groups from 28 sampling sites in spring (May), summer (July) and autumn (September) in 2017. Phytoplankton functional groups abundance and biomass varied significantly (P<0.05), both seasonally and spatially. Canonical correspondence analysis revealed that phytoplankton functional groups were mainly influenced by dissolved oxygen, permanganate index, water temperature, water depth, total nitrogen and N to P ratio in this basin. Sampling sites were divided into two groups by Non-metric multidimensional scaling analysis, and six phytoplankton species were selected as indicators of river wetland. Fragilaria virescen, Fragilaria capucina and Melosira granulata were used as monitoring indicator species in eutrophic water body. Ceratium hirundinella is the representative species of β-moderate pollution water body. Cymbella ventricosa prefer disturbed site by dredging and reservoir construction especially in the midstream. Chamydomonas ovalis can be used as the indicator of meso-eutrophic status shallow water with high mixing degree from surrounding farmlands in the downstream. The study aim is to provide a scientific basis for the biodiversity conservation and management of water quality.