摘　　要：我国正在开展系统的水质基准研究,对发达国家的水质基准理论和技术处于学习和研究阶段.物种敏感度分布分析、＂最少毒性数据需求＂以及基准的修正是水质基准推算中的若干关键技术.以氨氮水生生物基准为例,对这些关键技术进行了研究与探讨,提出在我国本土生物毒性数据缺乏的情况下可在种的水平上对水质基准进行推算.另外,可先利用全部生物的毒性数据进行物种敏感度分析,确定需重点获取的敏感生物类群的毒性数据,再用于基准推算,有望降低推算过程中对毒性数据量的需求.最后,基于中美生物物种分布的差异,借鉴美国修订国家水质基准的水效应比法,提出利用生物效应比法对美国国家水质基准进行修订以获取我国水质基准. Systematic study of water quality criteria is ongoing in China.The techniques for water quality criteria derivation used by developed countries are important references for China.Species sensitivity distribution analysis,＂minimum toxicity data requirement＂ and criteria revision are key technical issues in the calculation of water quality criteria.This study examined these issues,using the ammonia criterion for aquatic life as an example.The results suggest that,given the scarcity of toxicity data for local species in China,water quality criteria could be calculated on the species level rather than the genus level.The toxicity data requirement could also be reduced if the species sensitivity distributions for all the aquatic organisms were first analyzed,and the sensitive species which are critical for water quality criteria development were then identified.Finally,revisions to the national water quality criteria were proposed according to the water-effect ratio procedure recommended by the US EPA.Given the different characteristics between the Chinese and American biota,the present study proposed a biological effect ratio procedure to develop the water quality criteria in China by modifying the national water quality criteria of the United States.