The Characteristic of Phytoplankton Community Structure in the Coastal Area of Tianjin

ZHANG Pengruyan; LI Deliang; DAI Yuanyuan; GAO Yan; ZHANG Jingwei; YANG Wenying; LIU Kefeng; LIU Xianbin

Abstract：Three cruises were investigated in the coastal area of Tianjin in spring (May,2014),summer (July,2014) and autumn (October,2014).Phytoplankton community structure and seasonal variations were studied.A total of 49 species of phytoplankton were identified in the studied area,which belonged to 2 phyla and 23 genera.Among these species,44 species belonging to 20 genera in Bacillariophyta and 5 species belonging to 3 genera in Pyrrhophyta.In spring,16 species belonging to 12 genera were identified,the cell abundance of phytoplankton ranged from 0.55 × 104 ～28.9 ＜ 104 cells/m3 with an average of 5.45)× 104 cells/m3.The major dominant species were Noctiluca scintillans and Guinardia delicatula.In summer,18 species belonging to 38 genera were identified,the cell abundance of pthytoplankton ranged from 2.68 × 104 ～246 × 104 cells/m3 with an average of 40.70 × 104 cells/m3.The major dominant species were Coscinodiscus asteromphalus.In autumn,23 species belonging to 13 genera were identified,which abundance ranged from 2.70 × 104 ～83.7 × 104 cells/m3 with an average of 29.56 × 104 cells/m3.The major dominant species were Noctiluca scintillans and Guinardia delicatula.In spring,Pielou eveness index (J) ranged from 0.40 to 0.92 and Shannon-Weaver diversity index (H') ranged from 0.80 to 1.87.In summer,Pielou eveness index (J) ranged from 0.14 to 0.67 and Shannon-Weaver diversity index (H') ranged from 0.46 to 2.44.In autumn,Pielou eveness index index (J) ranged from 0.20 to 0.70 and Shannon-Weaver diversity index (H') ranged from 0.51 to 2.78.Overall,the deversity index was low.