INTERACTION OF COPPER AND HERBICIDE IN CONTAMINATED SOIL UNDER REMEDIATION

摘要

A vegetative experiment was carried out to determine the consequences of phytotoxicity and results of the remediation of soil contaminated with excess copper and residue of the herbicide metazachlor. The remediation treatments consisted of the soil enrichment with organic matter in the form of peat or earthworm humus, separately or in combination with CaCO_3. The test plant was oat. When no remediation was conducted, copper contamination at the level of 360 mg Cu-kg~(-1)reduced oat yield by 95% versus the yield obtained on natural (unpolluted) soil. It has been found out that combined presence of the metal and herbicide in soil compounded the negative effect of these pollutants compared to their separate effect. When copper concentration in soil was elevated, the decomposition of metazachlor in soil was slowed down. The best remediation effect such as improved yields of oat and depressed Cu concentration in plants was obtained by introducing to soil a combination of 3% by weight of soil dry matter of the earthworm humus and CaCO_3 in a doze according to 1.5 hydrolytic acidity.