春秋季南排河附近海域无机氮分布及变化特征探讨

Study on Distribution and Variation of Inorganic Nitrogen in the Sea Area off the Nanpaihe River in Spring and Autumn

通过对2012—2016年5a来南排河海域无机氮环境质量跟踪监测数据进行的总结对比,分析了该海域春秋季无机氮质量浓度的变化及分布特征。结果表明:该海域无机氮质量浓度2012-10变化范围为201.5~403.7μg/L,平均值为(339.1±46.5)μg/L;2014-09变化范围为167.9~287.3μg/L,平均值为(246.6±31.3)μg/L;2015-09变化范围为259.1~290.8μg/L,平均值为(275.8±7.4)μg/L;2013-04变化范围为139.8~251.5μg/L,平均值为(213.9±26.7)μg/L,2016-06变化范围为203.9~256.4μg/L,平均值为(229.5±14.0)μg/L。从季节变化上看,该海域秋季无机氮质量浓度高于春季。从分布特征来看,秋季存在明显高值中心,主要集中于调查区域的近岸一侧,向西北、东南一侧降低;春季无机氮分布较均匀。基本呈现近岸浓度高,离岸远的浓度低的规律。

The data obtained during the inorganic nitrogen environmental quality tracing and monitoring carried out in the sea area off the Nanpaihe River from 2012 to 2016 are summarized and compared,and the distribution and variation of inorganic nitrogen concentration in that area in spring and autumn are studied.The results show that the concentration of inorganic nitrogen changed from 201.5 to 403.7μg/L in October,2012,with an average of(339.1±46.5)μg/L;from 167.9 to 287.3μg/L in September,2014,with an average of(246.6±31.3)μg/L;from 259.1 to 290.8μg/L in September,2015,with an average of(275.8±7.4)μg/L;from 139.8 to 251.5μg/L in April,2013,with an average of(213.9±26.7)μg/L;and from 203.9 to 256.4μg/L in June,2016,with an average of(229.5±14.0)μg/L.From the view of seasonal changes,the concentration of inorganic nitrogen in the study area is higher in autumn than in spring.From the view of distribution characteristics,a central area in which the values of inorganic nitrogen concentration are obviously high occurs in autumn,and most of the high values occur mainly at the nearshore side of the study area.Toward northwest and southeast the concentrations of inorganic nitrogen become lower.In spring,the distribution of inorganic nitrogen is even,showing high concentration near the shore and low concentration far away from the shore.