摘要
对贵阳地区2008年10月1日至2009年9月30日大气降水样品中的NO3-浓度和δ15N组成进行了测定.结果表明,这一年大气降水中NO3-浓度加权平均值为0.45mg·L-1,δ15N组成的变化范围为-8.0‰～28.7‰,年均值为2.3‰,且主要来源于燃煤释放的含氮物质.NO3-浓度呈现冬高夏低的变化趋势,这可能是受降水量等因素的影响.但δ15N组成的季节变化与NO3-浓度有所不同,呈现秋冬季偏正,而春夏季偏负的特征,推测可能是由生物释放氮、大气雷电固氮及NOx本身的大气行为等引起δ15N组成的季节差异.
This study analyzed the concentrations of NO3- and values of δ^15N-NO3- in precipitation taken at Guiyang throughout one year from October 1, 2008 to September 30, 2009. The results indicated that the volume - weighted average concentration of NO3- was O. 45 rag·L^-1 , and the value of δ^15 N- NO3- ranges from - 8. 0‰ to 28.7‰ with the annum average of 2. 3‰ This implied that the source of NO3- was mainly from coal combustion. Significantly higher NO3- concentration in winter than summer suggested that NO3- concentration was mainly affected by precipitation. Seasonal variation of nitrogen isotopic composition was a bit different, with positive in autumn and winter and negative in spring and summer. This suggested that δ^15N-NO3- was mainly affected by biologically-released N, atmospheric nitrogen fixation and NOx behavior in the atmosphere.
出处
《环境科学学报》
CAS
CSCD
北大核心
2012年第4期940-945,共6页
Acta Scientiae Circumstantiae
基金
国家自然科学基金资助项目(No.40573006
40721002
40373039)~~
关键词
贵阳
降水
硝酸盐
氮同位素
季节变化
Guiyang
precipitation
NO3-
nitrogen isotope
seasonal variation
