洱海水中氨氮含量和化学耗氧量检测分析

Detection and Analysis of the Content of Ammonia-nitration and Chemical Oxygen Demand in the Water of Erhai Lake

目的:了解洱海水质情况。方法:采集洱海17个点的水样进行氨氮含量和化学耗氧量检测,分别采用纳氏比色法、高锰酸钾草酸滴定法进行测定,结果按照《地表水环境质量标准》进行评价。结果:洱海水中氨氮含量和化学耗氧量平均含量分别为(0.71±0.12)和(5.25±0.57)mg/L。水样氨氮含量均未超过Ⅲ类水标准,且南、北部含量差别有统计学意义,北部>南部;化学耗氧量均未超过Ⅰ类水标准,南、北部差别无统计学意义。结论:洱海北部污染较南部严重,主要为农业生产和人畜粪便污染所致。建议增强居民的环保意识,加强人畜粪便的无害化管理。

Objective：To investigate the water quality in Erhai Lake.Methods：Water samples from 17 sampling points in Erhai Lake were collected,Nessless colorimetric determination was applied to test the content of ammonia-nitration;and potassium permanganate oxalic acid titration was performed to test the chemical oxygen demand.The result was evaluated by ＂Surface Water Environmental Quality Standard＂.Result：The average content of ammonia-nitration and chemical oxygen demand in Erhai Lake were 0.71 ±0.12 mg/L and 5.25 ±0.57 mg/L respectively.The content of ammonia-nitration in the water samples did not exceed class Ⅲ water standards;and the ammonia-nitration content in the north part of Erhai Lake was more than that in the south part with statistic significance.While chemical oxygen demand did not exceed class I water standards.Besides,chemical oxygen demand in the north part of Erhai Lake had no statistic differences from that in the south part.Conclusion：Water pollution in the north part of Erhai Lake was more serious than that in the south part due to agricultural production and human and animal fecal pollution.Environmental awareness should be enhanced,and decontamination of feces should be strengthened.