光照对焦化废水植物毒性的影响

INFLUENCE OF ILLUMINATION ON THE PHOTOTOXICITY OF COKING PLANT EFFLUENT

利用植物毒性试验的方法,研究了不同光照条件下,焦化废水对黍和黄瓜种子发芽率、根长、根重、芽重的影响,结果表明,在光照条件下用焦化废水对植物进行培养,其毒性较在黑暗培养明显增强,将焦化废水在同样的光照条件下进行预处理后,其荧光光谱发生变化,用光预处理后的焦化废水在黑暗中对植物进行培养,其毒性随光预处理时间的增加而减弱,结果表明,光照培养条件下焦化废水植物毒性的增强,可能与光敏化作用或光照下形成寿命较短的毒物有关。

Using the method of phototoxicity testing and in the conditions of light or dark, the influenceof coking plant effluent on the monocotyledon——millet and dicotyledon——cucumber seeds havebeen studied by determining seeds germination percentage, roots length, roots weight and shoots weight. The results showed that when the plant seeds were cultured with coking plant effluent in the light condition, the toxicity increase significantly compared with the plant seeds were cultured in the dark. Pretreatment the coking plant effluent in the same light condition, the change of the fluorescence spectrum can been found, but the toxicity was weaken as the prolong of the pretreatment time when the plant seeds were cultrued in the dark. The results showed that the toxicity increase to coking plant effluent in the light condition may be brought by photosensitization of some compounds or the short-time toxicants formed in the process of illumination.