This study focuses on the water-soluble ion concentrations in the washing solution of leaves of different roadside tree species at three sites in Iran to estimate the ionic composition of the dry deposition of ambient air particulates. All considered water-soluble ion concentrations were significantly higher next to the roads with high traffic density compared to the reference site with low traffic density. The PCA results showed that Ca²⁺, Mg²⁺, ${NO}_3^{-}$ and ${SO}_4^{2-}$ originated mainly from traffic activities and geological sources, and Na⁺, Cl⁻, K⁺ and F⁻ from sea salts. In addition to sea salt, K⁺ and F⁻ were also originated from anthropogenic sources i.e. industrial activities, biomass burning and fluorite mining. Moreover, the concentration of the water-soluble ions depended on species and site. C. lawsoniana had significantly higher ion concentrations in its leaf washing solution compared to L. japonicum and P. brutia which indicates C. lawsoniana is the most suitable species for accumulating of atmospheric dry deposition. From our results, it can be concluded that sites with similar traffic density can have different particle loads and water-soluble ion species, and that concentrations in leaf-washing solutions depend on site conditions and species-specific leaf surface characteristics.

这项研究的重点是伊朗三个地点的不同路旁树种的叶子的洗涤溶液中的水溶性离子浓度，以估算周围空气微粒干沉降的离子组成。与交通密度低的参考地点相比，交通密度高的道路旁所有考虑的水溶性离子浓度均明显更高。PCA结果表明，Ca 2 ⁺，Mg ²⁺，${ñØ}_3^{-}$ 和 ${\mathrm{小号}Ø}_4^{2-}$主要来源于交通活动和地质资源和Na ⁺，氯^-，K ⁺和F ^-从海盐。除了海盐，K ⁺和F ^-也源于人为来源，即工业活动，生物质燃烧和萤石开采。此外，水溶性离子的浓度取决于种类和位置。C. lawsoniana相比，在其叶洗涤溶液具有更高显著离子浓度L.血吸虫和P. brutia指示C. lawsoniana是最适合累积大气干沉降的物种。从我们的结果可以得出结论，具有相似交通密度的站点可以具有不同的粒子负载和水溶性离子种类，并且洗叶溶液中的浓度取决于站点条件和特定于物种的叶子表面特性。