Preliminary insights into δ¹⁵N and δ¹⁸O of nitrate in natural mosses: A new application of the denitrifier method
2012
Liu, Xue-Yan | Koba, Keisuke | Takebayashi, Yu | Liu, Cong-Qiang | Fang, Yun-Ting | Yoh, Muneoki
Natural mosses have been employed as reactive and accumulative indicators of atmospheric pollutants. Using the denitrifier method, the concentration, δ¹⁵N and δ¹⁸O of moss nitrate (NO₃ ⁻) were measured to elucidate the sources of NO₃ ⁻ trapped in natural mosses. Oven drying at 55–70 °C, not lyophilization, was recommended to dry mosses for NO₃ ⁻ analyses. An investigation from urban to mountain sites in western Tokyo suggested that moss [NO₃ ⁻] can respond to NO₃ ⁻ availability in different habitats. NO₃ ⁻ in terricolous mosses showed isotopic ratios as close to those of soil NO₃ ⁻, reflecting the utilization of soil NO₃ ⁻. Isotopic signatures of NO₃ ⁻ in corticolous and epilithic mosses elucidated atmospheric NO₃ ⁻ sources and strength from the urban (vehicle NOₓ emission) to mountain area (wet-deposition NO₃ ⁻). However, mechanisms and isotopic effects of moss NO₃ ⁻ utilization must be further verified to enable the application of moss NO₃ ⁻ isotopes for source identification.
显示更多 [+] 显示较少 [-]