Fukui Prefectural University, Center for Arts and Sciences, 4-1-1 Kenjojima, Matsuoka, Eiheiji-cho, Yoshida-gun, Fukui, 910-1195, Japan.
Environ Sci Pollut Res Int. 2022 Feb;29(10):15018-15025. doi: 10.1007/s11356-021-16746-6. Epub 2021 Oct 8.
Long-range transported atmospheric pollutants (or transboundary pollutants) include trace metals with isotope ratios and compositions that vary from those of domestic pollutants, which threaten mountain ecosystems. These differences can be applied as indices to evaluate the influence of transboundary pollutants on mountain ecosystems. Mosses play important ecological functions in mountains and are sensitive to atmospheric deposition. Therefore, using these indices for moss biomonitoring can provide a more accurate indication of ecosystem health. However, studies on indices that are appropriate for moss biomonitoring are limited. Here, the effectiveness of moss biomonitoring using trace metal indices was examined to evaluate transboundary pollutants in mountainous areas in Japan. Transboundary pollutants in these areas originate from mainland Asia and are characterized by high lead isotope ratios, lead-to-zinc (Pb/Zn) ratios, and arsenic-to-vanadium (As/V) ratios. Given that the abundance of transboundary pollutants decreases with distance from mainland Asia, these three indices are also expected to vary with distance. The Pb isotope ratios were found to decrease with distance from mainland Asia; in contrast, the Pb/Zn and As/V ratios did not display any notable relationship with distance. These results are likely attributed to biological and environmental factors that affect trace metal content in moss. Thus, moss Pb isotope ratios are useful indicators of transboundary pollutants in Japan's mountains, offering an important tool for comparable moss biomonitoring studies in East Asia.
长距离传输的大气污染物（或跨境污染物）包括同位素比值和组成与国内污染物不同的痕量金属，这些污染物威胁着山区生态系统。这些差异可以作为评估跨境污染物对山区生态系统影响的指标。苔藓在山区具有重要的生态功能，对大气沉降敏感。因此，使用这些指标进行苔藓生物监测可以更准确地指示生态系统的健康状况。然而，适合苔藓生物监测的指标研究有限。在这里，我们检验了使用痕量金属指标进行苔藓生物监测的有效性，以评估日本山区的跨境污染物。这些地区的跨境污染物源自亚洲大陆，其特征是铅同位素比值、铅锌比（Pb/Zn）和砷钒比（As/V）较高。由于跨境污染物的丰度随与亚洲大陆的距离增加而降低，预计这三个指标也会随距离而变化。研究发现，苔藓中的铅同位素比值随与亚洲大陆的距离增加而降低；相比之下，铅锌比和砷钒比与距离之间没有明显的关系。这些结果可能归因于影响苔藓中痕量金属含量的生物和环境因素。因此，苔藓中的铅同位素比值是日本山区跨境污染物的有用指标，为东亚地区进行可比的苔藓生物监测研究提供了重要工具。
