以太湖流域为例探讨我国淡水生物氨氮基准

参照美国环境保护署(USEPA)《推导保护水生生物及其用途的国家水质基准的技术指南》和氨氮基准文件,结合我国水生生物区系特点,筛选出我国太湖流域和全国水域广泛存在的水生生物物种并收集相应的毒性数据,研究和推导了氨氮对我国太湖流域和全国水域淡水水生生物的毒理学基准.结果表明,25℃、pH=8时,太湖流域淡水水生生物氨氮基准最大浓度(CMC)和基准连续浓度(CCC)分别为3.20和1.79mg.L-1(以N计,下同),在4～34℃、pH为6.9～9.0的范围内,CMC和CCC的范围分别为0.24～25.78mg.L-1和0.20～4.51mg.L-1;25℃、pH=8时,国家氨氮基准值CMC和CCC分别为3.79和1.79mg.L-1,在0～30℃、pH为6～9的范围内,CMC和CCC的范围分别为0.39～42.88mg.L-1和0.26～5.11mg.L-1,与同样条件下的美国氨氮基准值相比,差异较小.太湖流域氨氮基准值与国家氨氮基准值相差很小.研究结果可为我国氨氮水质基准和标准的研究提供参考依据.

Development of aquatic water quality criteria for ammonia in freshwater ecosystem of China based on Lake Tai basin

This study aimed to develop aquatic water quality criteria for ammonia for the protection of freshwater ecosystem in China.The development of water quality was based on the Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and Their Uses(1985 Guidelines) and ammonia criteria documents issued by USEPA.After an evaluation on the characteristics of Chinese aquatic biota,the freshwater aquatic species existing widely in Lake Tai basin and in China were selected and their toxicity data were collected.The results showed that the criteria maximum concentration(CMC) and criteria continuous concentration(CCC) of ammonia in Lake Tai were 3.20 mg · L-1 and 1.79 mg · L-1,respectively.When pH ranged from 6.9 to 9.0 and temperature from 4~34 ℃,the values of acute and chronic ammonia criteria were 0.24~25.78 mg · L-1 and 0.20~4.51 mg · L-1,respectively.In comparison,the national CMC and CCC of ammonia were 3.79 mg · L-1 and 1.79 mg · L-1,respectively.When pH ranged from 6 to 9 and temperature from 0~30 ℃,the values of acute and chronic ammonia criteria were 0.39~42.88 mg · L-1and 0.26~5.11 mg · L-1,respectively.The results for the entire China were slightly higher than those of Lake Tai basin.The study provided important reference information for water quality criteria and standards for ammonia in China.