Summer and winter living coccolithophores in the Yellow Sea and the East China Sea

[摘要] This paper describes the distribution of living coccolithophores (LCs) in theYellow Sea and the East China Sea in summer and winter, and its relationshipwith environmental factors by canonical correspondence analysis (CCA). Wecarried out a series of investigations on LCs distribution in the Yellow Seaand the East China Sea in July and December 2011. 210 samples from differentdepths were collected from 44 stations in summer and 217 samples werecollected from 45 stations in winter. Totally 20 taxa belonging tococcolithophyceae were identified using a polarized microscope at the1000 × magnification. The dominant species of the two seasons wereGephyrocapsa oceanica, Emiliania huxleyi, Helicosphaera carteri, andAlgirosphaera robusta. In summer the abundance of coccolithophore cells andcoccoliths ranged 0–176.40 cells mL⁻¹, and0–2144.98 coccoliths mL⁻¹, with the average values of8.45 cells mL⁻¹, and 265.42 coccoliths mL⁻¹, respectively. Andin winter the abundance of cells and coccoliths ranged0–71.66 cells mL⁻¹, and 0–4698.99 coccoliths mL⁻¹, with theaverage values of 13.91 cells mL⁻¹ and 872.56 coccoliths mL⁻¹,respectively. In summer, the LCs in surface layer were mainly observed on thecoastal belt and southern part of the survey area. In winter, the LCs insurface layer had high value in the continental shelf area of section P. Thecomparison among section A, section F, section P and section E indicatedlower species diversity and less abundance in the Yellow Sea than those inthe East China Sea in both seasons. Temperature and the nitrate concentrationmay be the major environmental factors controlling the distribution andspecies composition of LCs in the studying area based on CCA.

Abbreviations: LCs: Living Coccolithophores; CCA: canonical correspondenceanalysis; DCM: Deep Chlorophyll Maximum

[学科分类] 地球化学与岩石