选用东海赤潮高发区两种典型赤潮藻种:东海原甲藻和中肋骨条藻,采用实验室一次性培养,参照东海海水的实际光照,研究了不同自然光强对两种赤潮藻生长及硝酸还原酶活性(NRA)的影响.结果表明在30~60 W.m-2光照范围内,东海原甲藻和中肋骨条藻均能正常生长,生长曲线皆为S型;而光强为9 W.m-2和0 W.m-2时,东海原甲藻和中肋骨条藻几乎无法生长.在实验设定的0~60 W.m-2范围内,两种藻的硝酸还原酶活性最大值NRAmax、最大生长速率μmax和终止生物量Bf随光照的变化趋势一致,说明光的强弱通过影响细胞硝酸还原酶活性大小间接影响藻类的生长.中肋骨条藻的最大生长速率及单位体积的NRAmax在数值上均远大于东海原甲藻,表明相对于东海原甲藻而言,中肋骨条藻能更好地利用硝酸盐.
Two typical red-tide algae,Skeletonema costatum and Prorocentrum donghaiense were selected as studied objects.The nitrate reductase activity(NRA) and the growth of the two algae under different illuminations through incubation experiment were studied.The illumination condition was consistent with in situ.Results showed that P.donghaiense and S.costatum could grow normally in the solar radiation ranged from 30-60 W.m-2,and the growth curve was"S"type.However,when solar radiation was below 9 W.m-2,the two alga could hardly grow.In the range of 0-60 W.m-2,three parameters(NRAmax,μmax,Bf) increased with the increasing of light intensity,indicating that the light intensity can influence the grow of alga indirectly through influencing the nitrate reductase activity.The μmaxand NRAmax in unite volume of Skeletonema costatum were higher than those of Prorocentrum donghaiense,indicating that Skeletonema costatum can better utilize the nitrate than Prorocentrum donghaiense.