Pan Huiyun, Li Xiaolu, Xu Xiaohua, Gao Shixiang
State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093, China.
J Environ Sci (China). 2009;21(3):307-12. doi: 10.1016/s1001-0742(08)62269-x.
The physiological effects of 4 herbicides (butachlor, quinclorac, bensulfuron-methyl and atrazine) on 3 submerged macrophytes (Ceratophyllum demersum, Vallisneria natans and Elodea nuttallii) were tested in laboratory. The variables of the relative growth rate and the photosynthetic pigment content showed that all of the tested herbicides affected the growth of the plants obviously, even at the lowest concentration (0.0001 mg/L). Except for the C. demersum treated with quinclorac at 0.005 and 0.01 mg/L, the relative growth rates of the plants were inhibited significantly (p < 0.01). Statistical analysis of chlorophyll a (Chl-a) contents was carried out with both the t-test and one-way ANOVA to determine the difference between the treatment and control. The results showed that Chl-a contents of the plants in all treatment groups were affected by herbicides significantly, except for the C. demersum treated with bensulfuron-methyl at 0.0005 mg/L. The decrease in Chl-a content was positively correlated to the dosage of the herbicides in most treatment groups. It was suggested that herbicides in water bodies might potentially affect the growth of aquatic macrophytes. Since the Chl-a content of submerged macrophytes responded to the stress of herbicides sensitively and directly, it could be used as a biomaker in environmental monitoring or in the ecological risk assessment of herbicide contamination.
在实验室中测试了4种除草剂（丁草胺、二氯喹啉酸、苄嘧磺隆和莠去津）对3种沉水植物（金鱼藻、苦草和伊乐藻）的生理影响。相对生长速率和光合色素含量等变量表明，所有测试的除草剂即使在最低浓度（0.0001 mg/L）下也明显影响植物的生长。除了用0.005和0.01 mg/L二氯喹啉酸处理的金鱼藻外，植物的相对生长速率均受到显著抑制（p < 0.01）。采用t检验和单因素方差分析对叶绿素a（Chl-a）含量进行统计分析，以确定处理组与对照组之间的差异。结果表明，除了用0.0005 mg/L苄嘧磺隆处理的金鱼藻外，所有处理组植物的Chl-a含量均受到除草剂的显著影响。在大多数处理组中，Chl-a含量的降低与除草剂的剂量呈正相关。研究表明，水体中的除草剂可能会对水生植物的生长产生潜在影响。由于沉水植物的Chl-a含量对除草剂胁迫反应敏感且直接，因此可将其用作环境监测或除草剂污染生态风险评估中的生物标志物。
