| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 4440390 | Atmospheric Environment | 2010 | 7 Pages |
Boron (B) concentrations and isotopic compositions were measured in the precipitations of Guiyang, China for one year. Most precipitation samples have boron concentrations of from 2.1 to 4.8 ng ml−1, and δ11B values of from +2.0‰ to +30.0‰. Boron concentrations and δ11B values of heavy rain samples are generally higher than those of light rain and snow samples. Anthropogenic inputs provided most of the SO42− and NO3−, which were predominant ions in the precipitation. The major cation Ca2+ in the precipitation was mainly originated from local dust.The total boron in precipitation from Guiyang is explained by the mixing model of three boron sources. Assuming a δ11B value of +45‰ for the seawater component, contributions of marine source, organic matter and biomass combustion, and coal combustion were estimated to be 32%, 49%, and 19%, respectively to the total boron in Guiyang precipitations. The coal combustion and biomass (and/or organic matter) combustion showed different contributions of boron to the rainwaters in different seasons, the former in cold season while the latter in summer season had a more marked influence on the chemical and isotopic composition of the rainwater. The largest contribution of seawater-originated boron was observed for the heavy rain samples, which was up to 68%. This study indicates that the atmospheric environment of Guiyang city was strongly influenced by human activities, and boron isotopic composition is of great sensitivity to anthropogenic sources and can be a powerful technique to trace various sources of atmospheric emissions and even their origins.
