施灰田及所产蔬菜的镉汞砷铬铅和铝含量变化及影响评价

蔬菜地田间施用粉煤灰试验结果表明 ,粉煤灰中镉、汞、砷、铬及铅5种元素的含量均较对照田的高 ,但施灰田所产蔬菜中这5种元素的含量均低于国家关于食品、蔬菜的卫生标准限值。粉煤灰中的铝含量虽比对照田的高 ,但由于粉煤灰偏碱性 ,使得土壤中的铝不易被植物吸收 ,故施粉煤灰不会产生铝的危害

Variation of Contents of Cd、Hg、As、Cr、Pb and Al in the Fields Applied with Flying Ash and Produced Vegetables

Contents of five elements namely Cd、Hg、As、Cr and Pb, in flyingash are higher than those of the contrast fields, but the contents of the elements in vegetables grown in the fields applied with the flying ash were lower than the limits of official standards. It has been known that appropriate concentration of Al can promote plants to grow, but while the content is over－dosage, it will harm plants. It is believed that application of flying ash over fields would not cause harmful effects, this may be explained that because of alkalinity of flying ash, it makes plants hardly adsorb the metal in the soil. Therefore, it may be concluded that application of flying ash causes no harmful effects.