Abstract: Principal component analysis(PCA) and ordination analysis(OA)on sulphur and heavy metal contents of 10 woody species in Chengde show that components Z₁ and Z₂ can mainly represent most of information reflected by 7 elements analysed,with an accumulative rate of >98%.Sulphur has a largest contribution to Z₁,while Fe,Zn,Mn and Pb have a stronger influence to Z₂.It is indicated that in the urban area of Chengde,sulphur pollution is most remarkable.Among heavy metals,Zn,Fe,Mn and Ph are serious pollutants, while Cu and Ni are not.In different parts of woody species,bark is most seriously polluted,twig is the second,and leaf is the lowest.

Key words: Woody species, Sulphur and heavy metals, Pollutant content, PCA, Chengde, precipitation pattern, winter wheat yield, fertilizer contribution rate, precipitation use efficiency, stepwise regression analysis