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Nine Platanus acerifolia (Ait.) Willd. trees growing in the Nanjing Children Teacher’s School, Nanjing,China, were selected to determine the contents of 13 chemical elements both in the 1994’s growth rings,C(Z, t), and in the soils near the roots, C’(Z, t), of the trees. The results showed that the relationship between C(Z, t) and C’(Z, t) followed the logarithmic linear correlation model, lgC’(Z, t)=a(Z)+b(Z) ig C (Z, t).Based on this model the chrono-sequences of chemical element contents in the soils were reproduced from those in the tree rings; i.e., the dynamic variations in the chemical element contents of the soils at the sites were traced. In this study the chrono-sequences of the chemical elements including Cd, Ph, Mn, Co and Zn in the soils near the roots of a Platanus acerifolia tree from 1957 to 1994 were established, and the background values of Cd, Pb, Mn, Co and Zn in the soil were calculated by taking the lowest values of the chrono-sequences of the element contents as upper limits of the background values.
Nine Platanus acerifolia (Ait.) Willd. Trees growing in the Nanjing Children Teacher’s School, Nanjing, China, were selected to determine the contents of 13 chemical elements both in the 1994’s growth rings, C (Z, t), and in the soils (Z, t) and C ’(Z, t) followed the logarithmic linear correlation model, lgC’ (Z, t based on this model the chrono-sequences of chemical element contents in the soils were reproduced from those in the tree rings; ie, the dynamic variations in the chemical element contents of the soils at the sites were traced. In this study the chrono-sequences of the chemical elements including Cd, Ph, Mn, Co and Zn in the soils near the roots of a Platanus acerifolia tree from 1957 to 1994 were established , and the background values of Cd, Pb, Mn, Co and Zn in the soil were calculated by taking the highest values of the chrono-sequences of the element contents as upper limits of the background values.