阿散酸在模拟池塘水体中的降解消除规律及对水生态的影响

Degradation-elimination rules and influences on aquatic ecosystems of arsenilic acid in simulating pond

【目的】研究模拟池塘水生态系统中阿散酸在水体与底泥中的降解规律及对水生态功能的影响.【方法】设立空白猪粪添加50、150和500 mg/L阿散酸的试验池,采集不同时间池中水及2 cm深处底泥样品,采用HPLC法测定阿散酸质量浓度,HG-AFS法测定总砷含量.【结果和结论】阿散酸在水体和底泥中的降解时间随药物质量浓度的增大而延长,降解半衰期分别为3.73-16.04和35.17-61.27 d,而总砷在底泥中呈现由浅入深的沉降趋势且消减缓慢.各生态池用药后对其溶解氧（DO）、p H和初级生产力（P/R）、底泥碱性磷酸酶、过氧化氢酶以及全氮和全磷含量等指标进行定期检测.结果表明：阿散酸质量浓度≥150 mg/L对水生态系统可造成不可逆转的影响,高质量浓度阿散酸对过氧化氢酶活性产生明显的抑制作用,底泥全氮含量呈现＂抑制-促进＂变化过程,各质量浓度下全磷含量均出现下降且呈现浓度依赖性关系。

【Objective】In this paper,by simulating the pond water ecosystem,degradation rule in water and sediment and the impact on aquatic ecosystem of arsanilic acid were studied. 【Method】Four miniaquatic pond ecosystems were established; the control was added 100 g pig manure and treated with different mass concentrations of 50,150 and 500 mg / L of arsanilic acid. Samples of water and 2 cm-depthsediment were taken. Arsanilic acid was determined by HPLC and the total arsenic contents were determined by HG-AFS. 【Result and conclusion】The half-life of arsanilic acid increased with the extension of the delivery drug concentration in pond water and surface sediment,which was 3. 73 to 16. 04 d and35. 17 to 61. 27 d,respectively,and the total arsenic showed a distinguished subsidence trend in sediment and degraded slowly. The values of dissolved oxygen（ DO）,p H,primary productivity（ P / R）,activities of sediment alkaline phosphatase and catalase,and the content of total nitrogen and phosphorus indicators were regularly detected. The results showed that 500,and 150 mg / L arsanilic acid could cause irreversibly detectable effects on the ponds. High mass concentration of arsanilic acid obviously inhibited catalase activities. The total nitrogen content of sediment showed an inhibition-promotion-change process,and all mass concentrations of the total phosphorus content declined and presented a concentration dependent relationship.