Elucidation of the long distance transportation of sulfate ion from Asia Continent based on sulfur isotope

基于硫同位素阐明亚洲大陆硫酸根离子的长距离输送

• 批准号: 06640632
• 负责人: SATAKE Hiroshi
• 金额: $ 0.26万
• 依托单位: Toyama University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1995
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-06640632/
• 关键词: Non-sea salt sulfate ion; Sulfur isotope; Asia Continent; Long distance transportation

Precipitation was collected every 24 hours during Oct. 1994-Dec. 1995. Samples collected were measured their major chemical compositions and sulfur isotope ratio. Chloride ion concentration is lower than 2 ppm in May-August and increases up to 15 ppm on and after Septmber. However most of Na/Cl ratios of precipitation samples with Cl<1 ppm range 0.1-0.5 and are lower than that of sea water (0.56). This suggests that chloride ion with anthropogenic origin significantly contributes in summer. NssSO4 concentration is 0-2.5 ppm in May-August and on and after September it increased up to 5 ppm. NO3/nssSO4 ratio in ppm gradually decreases from May (0.7-1.2) to December (0.2-0.6). Delta S of nssSO4 is-1 to 3 per mill in May-July. Delta S values higher than zero suggest that even in summer season sulfate ion is transported from Asia Continent. Sulfur isotope ratio is 0-3 per mill in September and 0-7 per mill in November-December. This suggests that the contribution of SO4 with continental origin increase with the changes of seasons from fall to winter. Delta S versus NO3/nssSO4 ratio plot shows that most precipitation distribute between two end points. One end point, delta S of 5 per mill and NO3/nssSO4 of 0.2, is typical for coal fume exhausted from northern China. The other end point, delta S of-2 per mill with NO3/nssSO4 of 1.5, is common for petroleum combustion gas in Japan. This fact suggests that sulfate ion transported from Asia Continent is mixed with local sulfate ion with various ratios.

在1994年10月至1995年12月期间，每24小时收集一次降水。对采集的样品进行了主要化学成分和硫同位素比值的测定。氯离子浓度在5 - 8月低于2 ppm，9月及以后增加到15 ppm。而Cl<1 ppm的降水样品的Na/Cl比值大多在0.1-0.5之间，低于海水的Na/Cl比值（0.56）。这表明，氯离子与人为来源显着贡献在夏季。NssSO 4浓度在5月至8月为0-2.5 ppm，9月和9月之后增加到5 ppm。NO3/nssSO 4比值（ppm）从5月（0.7-1.2）到12月（0.2-0.6）逐渐降低。5 ~ 7月nssSO_4的δ S值为-1 ~3 ‰。δ S值大于零表明，即使在夏季，硫酸根离子也是从亚洲大陆输送来的。9月硫同位素比值为0-3 ‰，11 ~ 12月为0-7 ‰。这表明，从秋季到冬季的季节变化，与大陆来源的SO 4的贡献增加。δ S与NO_3/nssSO_4比值图显示降水主要分布在两个端点之间。一个终点，δ S为5/mill，NO3/nssSO 4为0.2，是典型的从中国北方排放的煤烟。另一个终点，Δ S为-2/mill，NO3/nssSO 4为1.5，在日本石油燃烧气体中很常见。这一事实表明，从亚洲大陆输入的硫酸根离子与本地硫酸根离子以不同的比例混合。