Discovery of Natural Perchlorate in the Antarctic Dry Valleys and Its Global Implications

作者：Kounaves Samuel P^*; Stroble Shannon T; Anderson Rachel M; Moore Quincy; Catling David C; Douglas Susanne; McKay Christopher P; Ming Douglas W; Smith Peter H; Tamppari Leslie K; Zent Aaron P

来源：Environmental Science & Technology, 2010, 44(7): 2360-2364.

DOI：10.1021/es9033606

In the past few years, it has become increasingly apparent that perchlorate (ClO(4)(-)) is present on all continents, except the polar regions where it had not yet been assessed, and that it may have a significant natural source. Here, we report on the discovery of perchlorate in soil and ice from several Antarctic Dry Valleys (ADVs) where concentrations reach up to 1100 mu g/kg. In the driest ADV, perchlorate correlates with atmospherically deposited nitrate. Far from anthropogenic activity, ADV perchlorate provides unambiguous evidence that natural perchlorate is ubiquitous on Earth. The discovery has significant implications for the origin of perchlorate, its global biogeochemical interactions, and possible interactions with the polar ice sheets. The results support the hypotheses that perchlorate is produced globally and continuously in the Earth's atmosphere, that it typically accumulates in hyperarid areas, and that it does not build up in oceans or other wet environments most likely because of microbial reduction on a global scale.

• 出版日期2010-4-1