中文摘要：

凹凸棒石是一种富Mg的硅酸盐粘土矿物,具有抑制土壤的Cd活性的作用。江苏拥有丰富的凹凸棒石矿产资源,在利用凹凸棒石调控土壤Cd污染方面具有资源优势。文章报道了苏南地区典型Cd污染蔬菜地和稻田添加凹凸棒石粉的现场调控试验研究成果。结果显示：（1）当土壤Cd含量为0.3～0.45 mg/kg时,每年添加750 g/m2以上的凹凸棒石粉,可以使蔬菜Cd含量平均下降30%左右,凹凸棒石的最大有效添加量为1500 g/m2;（2）当土壤Cd含量约为3 mg/kg、p H〈6.5时,每年添加2000 g/m2的凹凸棒石粉,连续施用2年可使稻米Cd含量从0.5 mg/kg以上降低至0.2 mg/kg以下,稻米Cd含量与土壤p H呈显著负相关;（3）添加凹凸棒石可适度提高土壤的p H和CEC,同时还能降低农产品Cu、Zn含量,在防治耕地Cd污染上具有广阔应用前景。

英文摘要：

Attapulgite is a kind of clay mineral of Mg-rich silicate, resources in Jiangsu Province. As a kind of chemical remediation and it also constitutes a kind of abundant non-metallic mineral or immobilization material to tackle Cd-contaminated soil, its advantage in controlling heavy metal mobility is quite obvious. On the basis of choosing typical Cd-contaminated sites from vegetable garden and paddy land, a preliminary control test was systematically conducted to treat soil pollution of heavy metals so as to apply some doses of attapulgite powder in the southern area of Jiangsu Province. The related test data and controlling effect are reported in this paper to decrease Cd content of vegetable and rice from Cd-contaminated sites. Some conclusions have been reached： （1） when Cd concentration is 0.3-0.45 mg/kg in soil of the site, Cd content of vegetable can be decreased by 30% or so by applying attapulgite powder in excess of 750 g/m^2 , and maximum effective applying dose is 1500 g/m^2 to contaminated soil annually; （2） when Cd concentration is about 3 mg/kg and pH is lower than 6.5 in soils of the site, Cd content of rice can be dramatically decreased from more than 0.5 mg/kg to less than 0.2 mg/kg after 2 years＇ application of attapulgite powder in excess of 2000 g/m^2 to polluted soil annually, and there are distinct negative correlated relationship between Cd content of rice and pH in polluted soil, with the correlation coefficient being - 0.95; （3） the significance of applying attapulgite to the above- mentioned polluted soil is obvious in elevating pH values and cation exchange capacity （CEC）, and at the same time the element concentrations of Cu and Zn can be decreased in the vegetable or rice samples. It is thus held that the prospect of applying attapulgite to soil should be relatively huge or wide in curing Cd-contaminated lands.