PM2.5 particles with a diameter of 2.5 μm or less are the primary pollutant in the air. In this study, PM2.5 particles were generated by aerosol generator, and absorption and distribution of NH4 and NO3- in PM2.5 in Populus euramericana seedlings were studied by using 15N tracing technique. The results showed that water-soluble inorganic components (NH4 and NO3-) in PM2.5 can be absorbed effectively by P. euramericana. Absorption rate of NH4 and NO3- in P. euramericana leaves peaked one d...