磷化氢是大气中普遍存在的一种痕量气体,它是磷的气相载体,能够在湖泊水体和大气中进行迁移转化,参与磷的生物地球化学循环,从而对湖泊的富营养化造成影响。太湖是典型的磷限制型湖泊,富营养化问题严重,为了弄清磷化氢是太湖水体的源与汇以及其对湖泊富营养化的影响,本文利用静态箱观测法对冬夏两季太湖水-气界面磷化氢释放通量的日变化和季节变化进行观测,利用柱前两次低温冷阱富集-气相色谱/氮磷检测器联用技术对样品进行分析。结果表明,磷化氢(PH3)的释放通量日变化为白天低,晚间高。极大值出现在5:00,极小值出现在11:00~14:00。不同点位间水-气界面磷化氢释放通量在(0.04±0.01)~(3.32±0.13)ng·m^-2·h^-1之间,夏季PH,释放通量要高于冬季,平均释放通量为(1.34±0.20)ng·m^-2·h^-1。太湖水体是大气中磷化氢的源。
Phosphine, a ubiquitous trace gas in the atmosphere, acts as a carrier of gasous phosphorus in the P biogeochemical cycle. It can transfer between water body and ambient air and relates to the eutrophication of lakes. In this paper, a seriously eutrophicated and phosphorus restricted lake, Taihu Lake, is chosen to investigate whether it is a possible source and sink of phosphine and the role of phosphine during the eutrophication of Taihu Lake. Stationary box method was used to study the phosphine flux across the water-air interface of Taihu Lake in winter and summer. Samples were collected and measured by GC-NPD equipped with two cryotraps. The phosphine emission flux was found to be higher at night than that at day. The maximum diurnal emission flux of PH3 was at 5:00 am, and the minimum flux at 11:00-14:00 pm. The phosphine emission fluxes varied from (0.04±0.01) to (3.32±0.13)ng·m^-2·h^-1 at the different sampling sites of Taihu Lake. The average flux of phosphine in summer were (1.34±0.20)ng·m^-2·h^-1, higher than those in winter. Taihu Lake is an important source of phosphine to atmosphere.