西太平洋添加营养盐培养实验中挥发性卤代烃含量动态变化

于2018年10月9日~11月1日采集西太平洋表层海水,通过营养盐添加船基培养实验,研究了不同营养盐条件下浮游植物的生长及其释放挥发性卤代烃（VHCs）含量的动态变化规律.结果表明,与对照组相比,氮磷营养盐的添加对叶绿素a（Chl-a）的含量和三氯乙烯（C₂HCl₃）,四氯乙烯（C₂Cl₄）,一氯二溴甲烷（CHBr₂Cl）,三溴甲烷（CHBr₃）的释放量表现出显著促进作用,但促进程度与添加氮磷营养盐的浓度及比值密切相关.高浓度氮更有利于浮游植物的生长及C₂HCl₃和C₂Cl₄的释放.N/P比符合Redfield比值更有利于CHBr₂Cl和CHBr₃的释放.相比NO₃^--N,NH₄⁺-N的添加更有利于4种VHCs释放.

Variation of volatile halocarbon concentrations in the incubation experiments with the addition of nutrients in the western Pacific Ocean

Ship-based incubation experiments with the addition of nutrients were conducted with surface seawater of the western Pacific Ocean from October 9^th to November 1^th, 2018 to study the impact of the addition of nutrients on phytoplankton biomass and the production of volatile halocarbons (VHCs) by marine phytoplankton. The results showed that the addition of nutrients promoted the increase in the concentration of chlorophyll a (Chl-a) and the emissions of trichloroethane (C₂HCl₃), tetrachloroethylene (C₂Cl₄), chlorodibromomethane (CHBr₂Cl) and bromoform (CHBr₃) by phytoplankton, and the extent of promotion was closely related to the concentrations and ratios of nutrient addition. The maximum Chl-a, C₂HCl₃, and C₂Cl₄ concentrations occurred in the highest concentration of NO₃^--N. The ratio of N/P in accordance with the Redfield ratio could significantly increase CHBr₂ Cl and CHBr₃ concentrations. In addition, the release of four kind of VHCs with added NH₄⁺-N were higher than that of added NO₃^--N.