选定因素下湿地基质中氨氮释放的正交试验研究  

Orthogonal Experiment on Ammonia Nitrogen Release from Wetland Substrate Under Selected Factors

作　　者：廖晓数[1,2] 贺锋[1] 成水平[1] 吴振斌[1] 

机构地区：[1]中国科学院水生生物研究所淡水生态和生物技术国家重点实验室,湖北武汉430072 [2]中国科学院研究生院,北京100039

出　　处：《农业环境科学学报》2008年第1期291-294,共4页Journal of Agro-Environment Science

基　　金：国家“十五”科技项目(2002AA601021);国家杰出青年基金项目(39925007);湖北省科技攻关重大项目(2006AA305A03)

摘　　要：通过小型静态实验,研究了成熟复合垂直流人工湿地的基质在不同影响因素正交组合条件下氨氮的释放速率和变化。在控制温度T、pH值、溶氧(DO)及有机质(COD)的情况下,监测氨氮的释放速率。结果表明,氨氮的释放速率和变化受温度影响最大,一定范围内(15～35℃)温度越高,释放速率越大;溶氧对氨氮的释放无显著影响;基质本身含有丰富的有机质,因而较低COD浓度不构成氨氮释放的限制因素;湿地基质对pH值有很强的缓冲能力,进水pH值基本不影响氨氮的释放。The selected factors that influenced the releasing rates and changes of ammonia nitrogen （NH4-N） from the substrate in an integrated vertical flow constructed wetland were studied by using small-scale static experiments. NH4-N concentration of the effluent was measured while the temperature （T）, pH value, dissolved oxygen （DO） and organic matter （COD） of the influent were set as the orthogonal combined circumstances. Through the least three parallel groups of experiments under the condition of nine different combinations of the four environmental factors, the results indicated that NH4-N releasing rate was most significantly affected by temperature, and increased with the increase of temperature at 15-35 ℃. The releasing rate at 25 ℃ was about 2.9 times of that at 15 ℃, and the releasing rate at 35 ℃ was up to about 5.6 times of that at 15 ℃. The content of inorganic nitrogen was no more than 2% of total nitrogen in soil, so the ammonia nitrogen in the effluent was released mostly from the mineralizing process of organic nitrogen in the substrate, which may contribute to the activity of ammonifying bacteria that was greatly enhanced with the increase of temperature. DO values had no obvious influences on NH4-N releasing since ammonifying bacteria might be more adaptable to low DO. Low COD concentration was not a limiting factor for NH4-N releasing for the substrate was rich in organic matters itself. The substrate of wetland had a wide buffer to pH, so the influence of pH was not remarkable.

关 键 词：湿地 基质 释放 氨氮 正交实验 

分 类 号：X703.1[环境科学与工程—环境工程]