米氏凯伦藻对褶皱臂尾轮虫、卤虫和黑褐新糠虾存活的影响

Effect of Karenia mikimotoi on the survival of rotifer Brachionus plicatilis,brine shrimp Artemia salina,and Neomysis awatschensis

初步研究了一株米氏凯伦藻对褶皱臂尾轮虫(Brachionus plicatilis)、卤虫(Artemia salina)幼体和黑褐新糠虾(Neomysis awatschensis)的毒性效应和机制。研究发现米氏凯伦藻(Karenia mikimotoi)在较低密度下就能明显减少轮虫的种群数量,24hEC50仅为20个/mL左右;该藻的各组分毒性比较结果显示,只有藻液和细胞重悬液有这种毒害作用,而去藻过滤液和藻细胞破碎液的影响不明显,表明这种毒害作用可能是由于活的藻细胞引起的;在米氏凯伦藻中卤虫和黑褐新糠虾的存活数量也明显下降。结果表明,米氏凯伦藻赤潮可能通过直接影响存活从而对浮游动物产生影响。

In this paper,we analyzed the distribution of blooms caused by Karenia sp.in China and the toxicity of Karenia mikimotoi to Brachionus plicatilis,Artemia salina,and Neomysis awatschensis.The population of B.plicatilis was significantly decreased when exposed to K.mikimotoi at low densities and the 24h EC50 was about 20 cells/mL.Comparison of the toxicities of different algal fractions showed that the algal culture and re-suspended algal cells had the adverse effects,but the broken cells and filtrate showed little impact,indicating that the inhibitory effect was mainly related to the active whole algal cells.The survival of A.salina or N.awatschensis was significantly decreased when exposed to K.mikimotoi.The results suggest that K.mikimotoi blooms might directly impact zooplankton survival.