大气气溶胶干沉降对青岛近海水域几种微量金属的输入

TSP and PM10 samples were simultaneously collected at three sites in Qingdao area. The concentrations of several trace metals in the samples were determined by means of ICP-AES. The deposition fluxes to the Qingdao coastal waters were estimated. The morphology of aerosol particles and the existing form of metals in the samples were systematically studied. A new parameterization method was put forward based on a modified dry deposition model. The results indicated that the concentrations of TSP, PM10 and trace metals were closely related to the functionality of the locality. Obvious temporal variation of the concentrations was observed. The relative concentrations of anthropogenic metals in PM10 were clearly higher than those in TSP. During floating dust or smog period in springtime, the concentrations of TSP, PM10 and crustal metals were pronouncedly elevated, with little changes in the concentrations of anthropogenic metals. Both direct determination and indirect estimation showed that the deposition fluxes of crustal elements to the Qingdao coastal waters in springtime accounted for more than 50 percent of the annual fluxes, while those in summertime accounted for less than 10 percent. On the other hand, the temporal variation of the fluxes for anthropogenic elements was much less. The iron in aerosol samples is mainly presented in the form of Fe2O3, with a small amount of FeO mixed together. The morphology of aerosol particles is very rich. The relationship between the morphology and the composition is very complicated.

大气气溶胶干沉降是海洋中某些微量金属的重要外部来源，气溶胶的物理、化学性质对其沉降通量有很大影响。本研究以青岛近海水域为例，测定和了解气溶胶的主要物理、化学性质和控制因素；测定气溶胶干沉降向海洋输入微量金属的通量；从一个侧面了解大气气溶胶对近海水域生态环境的影响。这对海洋中微量金属循环和全球变化研究具有重大意义。