辽东湾毒害微藻潜在风险分布及环境关联

以18S rDNA V4区作为目标基因，利用自行设计的真核浮游植物鉴定引物V4（F/R），结合高通量测序技术，对辽东湾2014年四季海水中真核藻类多样性进行了检测.结果发现了辽东湾毒害藻类共29种，曾引发赤潮或褐潮的种类有19种，可导致鱼类大规模死亡的有8种，主要为甲藻门.有18种疑似为辽东湾新记录种，其中9种在中国海域未见报道；发现麻痹性贝毒（PSP）产毒藻8种，腹泻性贝毒（DSP）产毒藻2种，产虾夷扇贝毒素（YTX）产毒藻3种，神经性贝毒（NSP）产毒藻2种，溶血毒素（hemolysin）产毒藻13种，另外还有1种褐潮产毒藻（EPS）.辽东湾检出的毒害藻类中有8种自养型、1种异养型、20种混合营养型藻类.麻痹性贝毒、虾夷扇贝毒素、溶血毒素在夏季风险较高，神经性贝毒在秋季风险较高，腹泻性贝毒在春、夏季风险均较高，辽东湾东西两岸是贝毒风险高发区.辽东湾春季水温对YTX、NSP产毒藻影响显著负相关；夏季COD、Oil、DIN、Pb、Cd对各产毒藻类影响显著正相关；秋季各环境因子对各产毒藻类影响不显著；冬季Zn、As、Oil、DIN对各产毒藻类影响显著正相关，水温对各产毒藻类影响显著负相关，各产毒藻类与环境因子关联性有待于进一步研究.

An evaluation of the risks from toxic algae and their relationships with environmental conditions in Liaodong Bay

Taking the V4region of 18S rDNA as the target gene, we designed the primer V4 (F/R) and adopted high-throughput sequencing technology to evaluate the diversity and relative abundance of the eukaryotic phytoplankton community in different seasons of the year 2014 in Liaodong Bay. The results showed that there were 29 toxic algae in Liaodong Bay, including 8kinds of paralytic shellfish poisoning (PSP) algae, 2kinds of diarrhetic shellfish poisoning (DSP) algae, 3kinds of yessotoxic (YTX) algae, 2kinds of neurotoxic shellfish poisoning (NSP) algae, 13kinds of hemolysin, and a kind of exopolysaccharide (EPS) algae. Of these, 19toxic algae were reported to have caused either red or brown tides. Eight of the toxic algae, most of which belonged to Dinophyta, were capable of causing large-scale fish deaths. We found 18algal species that had been previously undetected or unreported in Liaodong Bay, in which 9algal species even had not previously appeared in other Chinese waters. The algal species had different trophic modes, including 8kinds of autotrophs, 20kinds of mixotrophs, and a kind of heterotroph. There were high risks from PSP, YTX, and NSP in summer;high risks from NSP in autumn; high risks from DSP in spring and summer; and the eastern and western waters of Liaodong Bay were prone to shellfish toxicity disasters. During spring, the water temperature was significantly and negatively correlated with the biomass of YTX and NSP algae. During summer, some environmental factors, such as chemical oxygen demand, oil, dissolved inorganic nitrogen (DIN), lead, and cadmium, were significantly and positively correlated with toxin-producing algae, but zinc, arsenic, oil, and DIN were positively correlated with toxic algae in the winter. The environmental factors were not significantly correlated with toxic algae in the autumn. The correlations between toxic algae and environmental factors should be further explored.