湛江棕囊藻对南美白对虾虾苗和多种鱼苗的毒性研究

Toxicity of Red Tide Alga Phaeoecystis globosa Scherffel from Zhanjiang against Young Penaeus vannamei Boone and Fish Fry

测定了湛江棕囊藻赤潮海水和棕囊藻(Phaeocystis globosa)对南美白对虾(Penaeus vannamei Boone)虾苗、青石斑鱼(Epinephelus awoara)、鲻鱼(Mugil cephalus)和尖吻鲈鱼(Latescal carifer)鱼苗的毒性。结果表明,棕囊藻对虾苗有一定的毒性,24 h LC50为1.0×109 cells L-1,去除囊泡液后的棕囊藻碎片对虾苗毒性较弱,细胞密度为1.0×109 cells L-1时,24 h虾苗的死亡率仅为10%,赤潮海水对虾苗无毒性;棕囊藻囊泡液对青石斑鱼有一定毒性,24 h LC50为囊泡液占海水总体积的10.9%,赤潮海水对青石斑鱼苗无毒性;棕囊藻对尖吻鲈鱼和鲻鱼鱼苗无毒性。

The toxicities of the alga of Phaeocystis globosa and the red tide seawater collected from the seaport in Zhanjiang City in April 2005, were detected. The dispersed alga colony had certain impact on the survival of young Penaeus vannamei Boone shrimps with 24 h LC50=1.0×10^9 cells L^-1. The mortality of the young shrimps was as low as 10% exposed for 24 h to 1.00×10^9 cells L^-1 of the alga colony removed of liquor. The red tide seawater had toxicity neither against the young shrimps nor against Epinephelus awoara （3 mm） fry. P. globosa exhibited no toxicity against the fry ofMugil cephalus and Latescal cclrifer. E. aWOClra fly were, however, sensitive to the alga, of which half died within 24 h in the presence of the alga colony liquor accounting for 10.9% of seawater volume.