PHYTOREMEDIATION OF INDUSTRIALLY- CONTAMINATED SITES USING TREES

摘要

Phytoextraction of Cd using Salix is likely to be suitable only for urban and agricultural soils with low- level contamination; unrealistically long time scales make this unsuitable for mine spoils or heavily contaminated Industrial sites. Under short-rotation coppice, willows can be expected to have a productive lifecycle of about 30 years. After this period the root bole could be relatively easily removed. It would also be important to harvest foliage. Short-rotation coppice systems in northern Europe generally rely on harvesting the trees during winter, often when the ground is frozen to provide easier access for agricultural machinery. However, in terms of metal removal, a substantial proportion of Cd is relocated to the foliage; leaf fall in autumn may actually increase the concentration and availability of the metal in the surface and would require earlier harvesting along with the woody stems.