藻类光合抑制法的水体综合毒性稳定测试条件研究

Conditions for Stably Detecting Comprehensive Toxicity of Water by Algal Photosynthesis Inhibition Method

藻类光合抑制法是极具潜力的水体综合毒性快速检测预警手段,并且稳定测量条件的确定对藻类光合抑制法毒性测试结果不可忽视。以蛋白核小球藻为受试藻种,根据农药敌草隆(DCMU)对藻类光合活性具有抑制作用这一特点,以α、Fv/Fm、Yield、rP 4种光合荧光参数的抑制率为分析对象,在不同质量浓度DCMU胁迫作用下,分别研究受试藻类质量浓度、藻液与样品混合体积比、反应温度这3种测试条件对水体综合毒性测量的稳定性影响。结果显示:当受试藻类在100~600μg·L^(-1)质量浓度范围内时,藻类质量浓度的变化对水体综合毒性测量没有显著影响;受试藻液与样品的混合体积比对毒性检测灵敏度有较大影响,受试藻液与样品的混合体积比为2:8时更有利于提高水体毒性检测的灵敏性;反应温度对水体综合毒性检测也有重要影响,其中20~35℃的温度范围更有利于提高水体综合毒性的检测精度。

Algal photosynthesis inhibition method is a potential method for rapid detection and early warning of comprehensive toxicity of water,and stable test conditions are critical to the toxicity test results of the algae photosynthetic inhibition method.In this paper,Chlorella pyrenoidosa is used as the test algae,and according to the characteristic that pesticide Dailon(DCMU)has an inhibitory effect on the photosynthetic activity of algae,the inhibition rates of the four photosynthetic fluorescence parameters(α,Fv/Fm,Yield,and rP)are as the analysis objects.Under the stress of different mass concentrations of DCMU,the influences of the three test conditions,including the mass concentration of the tested algae,the mixed volume ratio of the algae liquid to the sample,and the reaction temperature,on the stability of detecting the comprehensive toxicity of water has been studied separately.The results show that when the mass concentration of the tested algae is in the range of 100~600μg·L^(-1),the change of the algae mass concentration has no significant impact on the detection of comprehensive toxicity of water.However,the mixed volume ratio of the tested algae solution to the water sample has a great impact on the sensitivity of toxicity detection.When the mixed volume ratio of the tested algae solution to the water sample is 2:8,it is more conducive to improving the sensitivity of aquatic toxicity detection.In addition,the reaction temperature also has an important effect on the detection of comprehensive toxicity of water,and when the temperature is between 20℃and 35℃,it is more conducive to improving the detection accuracy of comprehensive toxicity of water.