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使用吹扫-捕集气相色谱法于2013年11月对渤海和北黄海海水中4种常见的挥发性卤代烃(VHCs)浓度进行了分析。结果表明:秋季渤海和北黄海表层海水中CHBr2Cl、CHBr3、C2HCl3和C2Cl4的浓度平均值和变化范围分别为7.03(4.23~12.63)pmol/L、19.61(5.99~55.00)pmol/L、20.37(1.68~58.25)pmol/L和41.03(10.84~96.94)pmol/L。受生物生产、人为输入、陆地径流等因素的共同作用,4种VHCs浓度呈现出不同的空间分布特征,总体表现为渤海海域由北向南递减,北黄海海域山东半岛以北、鸭绿江口浓度较低的特点。受地理位置和水文条件的影响,不同站位VHCs浓度在垂直分布上有较大差异,但最大值均出现在真光层。周日变化研究表明:VHCs在13∶00和17∶00浓度较大,7∶00和21∶00浓度较低,说明VHCs生产释放受光照和潮汐等因素的共同影响。采用Liss和Salter双膜模型估算了CHBr2Cl、CHBr3、C2HCl3和C2Cl4的海-气通量,结果分别为36.28(0.13~109.54)nmol/m2·d、85.96(-8.9~308.61)nmol/m2·d、191.71(0.10~386.67)nmol/m2·d和285.14(0.19~914.85)nmol/m2·d,表明在调查期间渤海和北黄海是大气中CHBr2Cl、CHBr3、C2HCl3和C2Cl4的源。
In November 2013, the concentrations of four common volatile halohydrocarbons (VHCs) in the Bohai Sea and North Yellow Sea seawater were analyzed using purge-trap gas chromatography. The results showed that the mean concentrations of CHBr2Cl, CHBr3, C2HCl3 and C2Cl4 in the surface waters of Bohai Sea and North Yellow Sea in autumn were 7.03 (4.23-12.63) pmol / L, 19.61 (5.99-55.00) pmol / L and 20.37 ~ 58.25) pmol / L and 41.03 (10.84 ~ 96.94) pmol / L. Under the combined effect of biological production, man-made input and land runoff, the concentrations of the four kinds of VHCs showed different spatial distribution characteristics. The overall performance of the Bohai Sea decreased from north to south, north of the Shandong Peninsula in the northern Yellow Sea and lower in the Yalu River estuary specialty. Influenced by the geographical location and hydrological conditions, the VHCs concentrations at different stations vary greatly in vertical distribution, but the maximum values appear in the euphotic layer. Changes in the sun show that: VHCs concentration at 13:00 and 17:00, 7:00 and 21:00 lower concentrations, indicating that the release of VHCs by light and tidal and other factors together. The sea-air flux of CHBr2Cl, CHBr3, C2HCl3 and C2Cl4 was estimated by Liss and Salter bi-membrane model. The results were 36.28 (0.13-109.54) nmol / m2 · d and 85.96 (-8.9-308.61) nmol / m2 · d , 191.71 (0.10 ~ 386.67) nmol / m2 · d and 285.14 (0.19 ~ 914.85) nmol / m2 · d respectively, indicating that Bohai Sea and North Yellow Sea were the sources of CHBr2Cl, CHBr3, C2HCl3 and C2Cl4 in the atmosphere during the survey.