Temporal and spatial variations and driving factors of phytoplankton in Yongjiang River estuary
To explore the temporal and spatial variations in phytoplankton community in small estuaries,we col-lected surface water samples from Yongjiang River estuary during wet,normal,and dry seasons and determined the main driving factors of phytoplankton community.A total of 358 species belonging to nine phyla and 123 genera were identified in all seasons.During wet,normal,and dry seasons,species number was 276,154 and 151,and the abundance was(170.45±225.43)×103,(51.92±30.28)×103 and(31.65±12.79)× 103 cells·L-1,respectively.Diatoms dominated the phytoplankton community,and the main dominant species were Cyclotella meneghiniana,Skeletonema costatum,and Paralia sulcata.Shannon diversity and Pielou evenness indices decreased from inside mouth to outside mouth in wet season,but there was no obvious spatial difference in normal season or dry season.Results of non-metric multidimensional scaling analysis and analysis of similarities showed that phytoplankton com-munity composition differed significantly among different regions(inside,at and outside mouth)and different sea-sons.In wet season,phytoplankton abundance was significantly positively correlated with temperature,dissolved inorganic nitrogen,and dissolved reactive phosphorus,but significantly negatively correlated with salinity.In nor-mal season,phytoplankton abundance was significantly negatively correlated with temperature.In dry season,it was not significantly correlated with environmental factors.Results of redundancy analysis showed that temperature,salinity,ammonium and dissolved reactive phosphorus explained the variations in phytoplankton community by 19.5％,11.9％,9.4％and 8.2％,respectively.These results revealed high dominance of diatoms and the main driving factors(temperature,salinity and nutrients)of phytoplankton community in Yongjiang River estuary.
Yongjiang River estuaryphytoplanktoncommunity structureenvironmental factorredundancy analysis
万方数据
维普
