近海污染物对海洋浮游植物生长及生化组成影响的比较研究

Comparison of the effects of coastal pollutants on the growth and biochemical composition of marine phytoplankton

威氏海链藻(Thalassiosira weissflogii)属沿海中心硅藻纲,是海洋硅藻的模式种之一。实验探讨氮营养盐(硝酸盐,N,c(N)分别为8.0,16.0,32.0,64.0μmol/L)、石油烃(0号柴油分散液,WAFs,c(WAFs)分别为0,0.1,0.5,1.0,5.0 mg/L)、抗生素(土霉素,c(OTC)分别为,0,1.0,3.0,5.0,10.0 mg/L)等3类近海常见污染物对威氏海链藻细胞生长及生化组成的影响。结果表明,3类近海常见污染物对藻生长(即藻细胞密度)、叶绿素a合成、蛋白质生成、藻细胞抗氧化能力(即超氧化物歧化酶活性)、脂质过氧化(即丙二醛含量)的影响程度分别为WAFs>N>OTC、N>OTC>WAFs、N>WAFs>OTC、WAFs>N>OTC、OTC>>N>WAFs;影响程度的差异,揭示了近海各污染物的毒性作用机制及靶位不同。

Thalassiosira weissflogii, a coastal centric diatom, was cultivated at different concentrations of nitrogen nutrients （nitrate, N, 8.0, 16.0, 32.0, 64.0μmol/L）, petroleum hydrocarbons （water accommodated fractions of No.0 diesel oil, WAFs, 0, 0.1, 0.5, 1.0, 5.0 mg/L）, and antibiotics （oxytetracycline, OTC, 0, 1.0, 3.0, 5.0, 10.0 rag/L）. The results showed that both cell growth and biochemical compositions were affected by N, OTC, and WAFs addition. The influence degree on the algal growth （i.e. cell density）, the synthesis of chlorophyll a and proteins, algal cell antioxidant capacity （i.e. superoxide dismutase activity）, and lipid peroxidation （i.e. malondialdehyde content） was WAFs〉N〉OTC, N〉OTC〉WAFs, N〉WAFs〉OTC, WAFs〉N〉OTC, and OTC 〉〉 N〉WAFs, respectively. According to the difference of influence degree, the toxic mechanism and target organisms of these three kinds of marine coastal pollutants were different.