中性环境中铝盐絮凝剂对典型作物的生态毒性效应

采用种子发芽和根伸长抑制的陆生生态毒理方法，在中性条件(pH=7.0)下对铝盐絮凝剂(AlCl₃)的生态毒性效应进行了研究.结果表明，AlCl₃溶液在pH=7.0时，与其酸性条件(pH=4.0)相比对萝卜、白菜和小麦等受试作物种子发芽和根伸长均表现出抑制作用，且发芽抑制率和根伸长抑制率与铝浓度均呈极显著相关(P＜0.01).尽管在酸性条件下AlCl₃对白菜和小麦根伸长抑制效应比相同浓度中性条件更为强烈，但对萝卜根伸长的抑制程度在相同铝浓度条件下则是pH=7.0时明显大于pH=4.0时，在低浓度时萝卜发芽抑制率也是中性条件明显高于酸性条件.同时，铝盐在中性条件下对萝卜、白菜的发芽和根伸长产生明显抑制效应的起始浓度低于酸性条件(＜2.0 mg·L^-1).

Ecological toxicity of aluminum-based coagulant on representative corps in neutral environment

By the terrestrial ecotoxicological methods of seed germination and root elongation, and with aluminum-based coagulant AlCl3 which was widely used in wastewater- and water treatment as an example, this work studied the toxicological effects of aluminum-based coagulants on representative crops, including radish Raphanus sativus, cabbage Brassica chinensis and wheat Triticum aestivum, over a range of exposure concentrations under the neutral condition (pH= 7.0), with contrast to an acid condition (pH= 4.00). The results indicated that there was a significantly positive correlation between the concentration of AlCl3 and the inhibitory rate of root elongation and seed germination either under pH 7.0 or 4.0 (P < 0.01). Cabbage and wheat was more susceptive to AlCl3 toxicity under acid than under neutral condition, while radish was in adverse. The minimum inhibitory concentration of AlCl3 (< 2.0 mg x L(-1)) was lower under neutral than under acid condition.