天津城郊污染区土壤Cd的赋存形态及其对蔬菜的影响

介绍了天津城郊污染区土壤Cd元素的赋存形态,探讨了Cd的赋存形态对蔬菜的影响。研究区土壤中Cd的污染程度高,以蔬菜种植为主,水溶态、离子交换态和碳酸盐态这几种容易(或在一定条件下容易)被作物吸收的Cd含量占65.2%;而有机态结合态、铁锰氧化物结合态和残渣态等难被作物吸收的Cd含量低,仅占23.3%。污染区大白菜、芹菜和油麦菜3种蔬菜中的Cd与土壤中Cd的全量、Cd的多种形态都呈较明显的正相关。油菜、芹菜和油麦菜样品存在超标现象。

Speciations of Cd in soils in a polluted area in the suburbs of Tianjin Municipality, China

This paper introduces Cd speciations in polluted soils in the suburbs of Tianjin and discusses its influence on vegetables. Soils in the study area are heavily polluted and mostly are used for vegetable cultivation.The contents of water-soluble phase Cd, ion-exchangeable phase Cd and carbonated phase Cd,which are easily (or easily under certain conditions) absorbed by crops,account for 65.2% of the total Cd content;whereas the contents of Fe/Mn oxide phase Cd,organic matter phase Cd and residual phase Cd, which are difficultly absorbed by crops,only account for 23.3%.There are significant positive correlations between Cd in cabbage,cel- ery and romaine leaf and total Cd and its speciations in soils.The Cd contents in cabbage,celery and romaine leaf exceed the provided standards.