Preliminary aquatic life criteria development and ecological risk assessment of ammonia in seven major river basins in China

七大流域氨氮水生生物水质基准与生态风险评估初探（英文）

Ammonia is one of the basin indices which are nation-controlled in the waterenvironmental management. In order to assess the differences of ammonia criteria indifferent basins, 7 major basins are used for the study object, including Songhua River,Liaohe River, Haihe River, Yellow River, Huaihe River, Yangtze River and ZhujiangRiver, referring the water environmental criteria technology of the United StatesEnvironmental Protection Agency, based on the effects of water characteristics on theecotoxicity of ammonia, and in summer and non-summer situation, aquatic life criteriais derived for ammonia. The results showed that: (a) The differences between thecriteria values in different basins and different seasons were significant. The differencesbetween the criteria values in different basins were greater than 6 times, while those indifferent seasons in the same basin were greater than 2 times. (b) The summer acuteand chronic criteria for Huaihe River were 0.37 mg/L and 0.06 mg/L while thenon-summer values were 0.81 mg/L and 0.15 mg/L. Both the summer and thenon-summer values were lowest in all of the seven basins. (c) The preliminaryassessment of Ammonia exposure ecological risk indicated that was the lowest inZhujiang River, and it was much lower in Songhua River, Liaohe River and YangtzeRiver, and was higher in Yellow River, and the highest in both Haihe River and HuaiheRiver. Haihe River has 7 sections while 2 in high risk, and Huaihe River has 27 sectionswhile sixteen in high risk. According to the differences of the criteria values for ammoniain seven basins in different seasons and difference of ammonia ecological riskassessment, it is suggested that it should be managed by different policies.

氨氮是我国流域水环境管理的国控指标之一,为评估不同流域的氨氮基准差异性,以七大流域(松花江流域、辽河流域、海河流域、黄河流域、淮河流域、长江流域和珠江流域)为研究对象,基于水质参数对氨氮毒性的影响,借鉴US EPA(美国国家环境保护局局)水环境基准技术方法,分夏季和非夏季2种情况推算了各流域氨氮水生生物基准值.结果显示:a)流域和季节的不同导致氨氮基准值的差异均很明显,不同流域的氨氮基准值差异可超过6倍,同一流域不同季节的氨氮基准值差异可超过2倍。b)淮河流域夏季和非夏季氨氮基准值均为最低,夏季氨氮急、慢性基准值分别为0.37和0.06 mg/L,非夏季分别为0.81和0.15 mg/L。c)氨氮暴露生态风险初步评估结果表明,珠江流域风险较小;松花江流域、辽河流域、长江流域次之;黄河流域风险较大;海河流域和淮河流域风险最大,海河7个断面中有2个存在高风险,淮河27个断面中16个存在高风险.根据各流域不同季节氨氮基准值及氨氮暴露生态风险的差异,建议对不同流域、不同季节实行差异化管理。