[Effects of typical organic pollutants on marine dioxide carbon system in simulated experiments]

The effects of typical organic pollutants (ethanol, acetone, ON, OP) on pH and marine carbon dioxide system were investigated in laboratory simulated experiments. The results indicated that the growth of biological carbon fixed system was promoted by ethanol and acetone of low concentration (< 0.5 mmol x L(-1)) (t = 7 d). So pH increased while DIC, HCO3(-) and p(CO2) significantly decreased compared to the controls (p <0.01). The concentrations of ethanol and acetone which resulted in the maximum decrease of carbon dioxide parameters were 0.25 mmol x L(-1) and 0.1 mmol x L(-1), respectively. When the infusion of organic pollutants were higher than the "critical concentration", the carbon dioxide parameters increased and pH decreased compared to the controls with the decrease of carbon fixation strength of alga. As for ON and OP groups, when they were in the range of experimental concentration, decreasing trends of inorganic carbon in sea water were always found. The concentration changes of DIC (DeltaDIC) under the press of the four typical organic pollutants were significantly negatively correlated with the changes of dry weight of alga (p < 0.01 or p < 0.05) and the coefficient parameters were -0.902, -0.945, -0.898 and -0.918, respectively (t = 7 d). The main controlling factor to the variation of carbon dioxided system was the adaption of biological carbon fixed system to different concentration and kind of organic pollutants.