0#柴油和原油的水溶性成分对小球藻(Chlorella vulgaris)生长的影响

采用室内培养方法,研究了不同浓度0#柴油和原油的水溶性成分(Water accommodated fraction,WAF)对小球藻(Chlorella vulgaris)的生长影响及其差异.结果显示,低浓度的0#柴油WAF(0.30、0.10 mg/L)和原油WAF(1.17、0.58 mg/L)能够促进小球藻的生长,且0#柴油WAF的0.10 mg/L实验组和原油WAF的0.58 mg/L实验组在96h时,小球藻细胞密度显著高于对照组(P＜0.05);而高浓度的0#柴油WAF(8.10、2.70、0.90 mg/L)和原油WAF(9.36、4.68、2.34 mg/L)会抑制小球藻的生长.0#柴油和原油WAF对小球藻的96 h-EC50分别为3.34、6.54 mg/L,NOEC分别为0.30、1.71 mg/L,LOEC分别为0.90、2.34 mg/L.0#柴油WAF的毒性高于原油WAF,0#柴油和原油水溶性成分的组分差异是影响二者毒性强弱的主要因素.

Effects of Water Accommodated Fraction of No.0 Fuel Oil and Crude Oilon the Growth of Chlorella vulgaris

We performed 96 h growth tests in a batch-culture system to study the effects of water accommodated fraction (WAF) of No.0 fuel oil and the crude oil on the growth of Chlorella vulgaris. The results showed that the growth of algal cells was inhibited by WAF of No.0 fuel oil at the concentrations of 8.10 mg/L, 2.70 mg/L and 0.90 mg/L. As for WAF of the crude oil, the inhibiting concentrations were 9.36 mg/L, 4.68 mg/L, and 2.34 mg/L. After 96 h, the densities of algal cells in the 0.10 mg/L No.0 fuel oil group and the 0.58 mg/L crude oil group were significantly higher than that in the control groups. In the contrast, the growth of algal cells was promoted by WAF of No.0 fuel oil at 0.30 mg/L and 0.10 mg/L, and by WAF of the crude oil at 1.17 mg/L and 0.58 mg/L. The 96 h median effect concentrations (EC50) of WAFs of No.0 fuel oil and the crude oil were 3.34 mg/L and 6.54 mg/L respectively. The no observed effect concentrations (NOECs) of WAFs of No.0 fuel oil and crude oil were 0.30 mg/L and 1.71 mg/L respectively. The lowest observed effect concentrations (LOECs) of the two were 0.90 mg/L and 2.34 mg/L respectively. The toxicity of WAF of No.0 fuel oil was higher than that of the crude oil, which mainly resulted from the differences in the components of the two WAFs.