Abstract: Based on the determination of the Pb, Cu, Zn, and Cd concentrations in cedar(Cedrus deodara) needles in Luoyang urban area, this paper analyzed the distribution of these heavy metals in the atmosphere. The needle samples were collected from 10-15 years old trees (YS), fallen needles of 10-15 years old trees (YD), 20-30 years old trees (LS), and fallen needles of 20-30 years old trees (LD), and the sampling sites were at 11 different locations with different degrees of heavy metals air pollution in residential, commercial, industrial, and scenic regions. The mean values of the needles Pb, Cu, Zn, and Cd concentrations in the four regions were 1.606, 3.385, 18.151, and 0.198 mg·kg^-1, respectively. There were significant differences in the Cu and Zn concentrations, but no significant differences in the Pb and Cd concentrations among YS, YD, LS, and LD. The Pb, Cu, and Zn concentrations in the needles differed significantly with sampling sites, and decreased in the order of industrial region > commercial and residential region > scenic region, while the concentration of Cd had little difference. The spatial variability of test heavy metals in cedar needles was mainly affected by the industrial discharge of the metals, and could objectively indicate the heavy metals air pollution. It was suggested that cedar could be used as the good tree species indicating the heavy metals pollution of urban air environment.

Key words: Indica rice, Photoperiod-temperature sensitive genie male-sterile lines, Conversion of the fertility, Temperature sensitive stage, Critical temperature