INVESTIGATION OF TOXIC LEVEL OF SOIL LEAD POLLUTION BY PHYTOTOXICITY METHOD

Heavy metal pollution in soils is one of the most important environmental problems. Heavy metal accumulation in soils has an important influence. It is not only on the fertility of soils and functions of ecosystem but also on the health of animals and human beings via food chains. Heavy metals have important causes in plant structure decreases the crop quality and yield due to inhibition of plant physiological activity, decreasing fertility and killing plants. Tolerance of plant to heavy metal toxicity depends on plant variety, element type, time of stress, plant tissue and organ. Therefore, knowing like a lead heavy metal quantity, and as well as damage formation process is important for plant growth and development. In present investigation Ailanthus altissima and Lepidium sativum L. plans were tested to measure toxicity of lead concentration in soil and aqueous solution. Seedling of the plant seeds was completely inhibited. There were increasing tolerances to lead concentration by Ailanthus altissima.