海洋气溶胶采样、提取方法对痕量元素溶解度的影响

The effects of sampling and extraction methods on the solubility of trace elements in marine aerosols

海洋气溶胶中痕量元素的溶解度对于精确评估大气输送量及痕量元素的生物地球化学行为具有重要的意义。目前文献报道的气溶胶中痕量元素溶解度的变化范围很大,除气溶胶自身的物理化学性质及其在迁移过程中受大气过程的影响外,不同的采样和提取方法对结果引入的差异不容忽视。对于痕量元素含量较低的海洋气溶胶,这一问题更为突出,不仅影响各研究结果之间的可比性,也不利于数据的解读。为此,“痕量元素及其同位素的海洋生物地球化学研究”(GEOTRACES)国际海洋研究计划在2008年发起了国际气溶胶采样及分析方法的互校实验。根据互校实验结果展开综述,从海洋气溶胶的采样器、采样膜、淋溶和消解方法等方面进行比较,并给出海洋气溶胶采样和提取的最优方法建议。

The solubility of trace elements in marine aerosols plays an important role in precisely assessing the atmospheric flux and the biogeochemical behavior of trace elements in the ocean.The previous studies showed that there existed significant difference in the solubility of trace elements in the aerosols.In addition to the impact of its own physical and chemical properties and the effect of atmospheric process during its migration,the difference derived from different sampling and extraction methods may be the crucial reason for this phenomenon.This problem is more prominent for the marine aerosol with low trace element content.These systematic errors may not only affect the comparability of previous studies,but also not conducive to the interpretation of data.Therefore,an international science plan,named as“An International Study of Marine Biogeochemical Cycles of Trace Elements and their Isotopes(GEOTRACES)”in 2008 launched marine aerosol international inter-calibration experiments.This article reviews the results from the 2008 GEOTRACES aerosol inter-calibration experiments,compares the samplers,filters,leaching and digestion methods of marine aerosol,and thereby providing suggestions on the most optimized methods of sampling and extracting marine aerosols.