Tracking the algal origin of the bloom in the Yellow Sea by a combination of molecular, morphological and physiological analyses

Shao Jun Pang (1) , Feng Liu (1, 2) , Ti Feng Shan (1) , Na Xu (1, 2) , Zhi Huai Zhang (1) , Su Qin Gao (1) , Thierry Chopin (3) , Song Sun (1)

1 CAS - Chinese Academy of Sciences [Beijing]
2 UCAS - Graduate University of Chinese [Beijing]
3 UNB - University of New Brunswick

In 2008, Qingdao (36°06′ N, 120°25′ E, P. R. China) experienced the world largest drifting macroalgal bloom composed of the filamentous macroalga . No convincing biological evidence regarding the algal source is available so far. A series of field collections of both sp. and waters in various sites along Jiangsu coasts were conducted in March to May of 2009. Density of microscopic germlings in the waters sampled from different sites ranged from 7 to 3140 individuals L, indicating the wide-spreading and long-term existence of the algae in the investigated region. Morphological and the nuclear ribosomal internal transcribed spacer ITS nrDNA and the chloroplast-encoded L gene comparisons of 26 algal samples revealed that the algae collected from land-based animal aquaculture ponds mostly resembled the dominating blooming alga in 2008. Mismatch of farming period with the occurrence of the green tide bloom, as well as the negative identification results of the sampled green algae from the rafts eliminated rafts as the principal and original source of the dominating blooming alga.

Mots clés: Green tide; Algal bloom; Eutrophication; ITS nrDNA

Shao Jun Pang, Feng Liu, Ti Feng Shan, Na Xu, Zhi Huai Zhang, et al.. Tracking the algal origin of the bloom in the Yellow Sea by a combination of molecular, morphological and physiological analyses. Marine Environmental Research, 2010, 69 (4), pp.207. ⟨10.1016/j.marenvres.2009.10.007⟩. ⟨hal-00564777⟩