Individual tree species differ significantly in ability to transport metals from roots to shoots and to accumulate them in individual plant parts. Pulford and Watson [19] concluded that within the tree Pb, Cr, and Cu are usually immobilized in roots while Cd, Ni, and Zn are more easily transported to shoots. Figure 2 indicates opposite pattern for Cr and Ni but different soil properties of different sites and/or different sampling time and climate conditions must be taken into account in this case.

Nissen and Lepp [22] found that the concentrations of Cu and Zn varied between plant parts and between species. There was no consistent pattern of metal concentration. Copper concentrations decreased in the order twigs > leaves > wood > bark, and those of Zn in the order leaves > bark > twigs > wood indicating the low retention of Zn in the xylem tissues. Salix x sericans and Salix cinerea had high concentrations of both metals; S. purpurea had high concentrations of Zn but low concentrations of Cu, whilst Salix fragilis and Salix viminalis had low concentrations of both metals. Concentration factors for both elements in shoot tissues were consistent, despite the variations in associated metal concentrations. Concerning cadmium the willow leaves contain approximately 1.6fold higher level compared to wood representing 49% of total shoot cadmium content. Roots contained 90% of cadmium contents in shoots [23]. Distribution of arsenic within tree was leaves > branch bark > stem bark > wood, where stem position on the tree was significant for leaf arsenic content [24].

Body Detox Made Easy

Body Detox Made Easy

What exactly is a detox routine? Basically a detox routine is an all-natural method of cleansing yourbr body by giving it the time and conditions it needs to rebuild and heal from the damages of daily life and the foods you eat and other substances you intake. There are many different types of known detox routines.

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