Characterization of ultraphytoplankton pigments and functional community structure in Xiangxi Bay, China, using HPLC-CHEMTAX

Abstract

To characterize the ultraphytoplankton community structure and understand its succession, we investigated photosynthetic pigment concentration and composition; algae phyla composition and abundance; and environmental factors in Xiangxi Bay (XXB) from February to December 2013. High-performance liquid chromatography (HPLC) analyses revealed eight diagnostic pigments: Fucoxanthin, Neoxanthin, Violaxanthin, Alloxanthin, Lutein, Zeaxanthin, Chlorophyll b and Chlorophyll a. The temporal differences between seven of the pigments (all excepting Neoxanthin) were significant (P 0.05). A chemical taxonomy (CHEMTAX) calculation identified seven phyla of ultraphytoplankton: cryptophytes, chlorophytes, cyanobacteria, diatoms, euglenophytes, chrysophytes, and dinoflagellates. The temporal differences between five of the phyla (except chlorophytes and euglenophytes) were significant (P 0.05). The redundancy analyses demonstrated that the key environmental factors for the succession were N-NH4+ and P-PO43–. Application of the HPLC-CHEMTAX method has provided the first analysis of ultraphytoplankton community structure in XXB, and our findings also show that environmental factors influence the succession of ultraphytoplankton over time.

Keywords

• Xiangxi Bay
• photosynthetic pigments
• ultraphytoplankton
• HPLC-CHEMTAX
• environmental factors