【摘要】 通过对对照土壤和铬污染土壤的模拟酸雨土柱淋溶试验,研究了模拟酸雨作用下土壤中重金属Cr、Zn、Cu的释放特征,比较了对照土壤与铬污染土壤重金属释放特征的差异。结果表明,模拟酸雨pH值越低,3种重金属的释放量越大;两种土壤中3种重金属对酸雨的敏感性差异为Cr>Zn>Cu,对照土壤对重金属吸附能力为Cu>Zn,铬污染土壤对重金属吸附能力为ZnCr>Cu,说明金属Cr对土壤中Cu、Zn的吸附能力有一定的影响作用;土壤中Cu与Zn的累积释放量之间均存在着显著的线性关系,而在铬污染土壤中Cu与Cr的累积释放量之间呈现显著指数关系;在pH4、pH5的模拟酸雨作用下土壤中释放的Cr年平均浓度分别超标127、104倍,酸雨加速了铬污染土壤中Cr的释放,从而增加了环境中Cr对人类直接或潜在的危害性。更多还原

【Abstract】 Desorptive behavior of Cr,Zn,Cu in chromate-polluted soil was studied by contrasting normal soil with the chromate-polluted soil on the basis of simulated acid-rain column shower,and the desorptive difference between the two soils was compared.The results showed that the larger desorptive quantities of the three heavy metals release,the lower pH value of the simulated acid-rain is,the sensitive difference of the two soils for the three heavy metals was Cr>Zn>Cu,whereas adsorption capacity of contrasting soil to the heavy metals was Cu>Zn;the adsorptive capacity of chromte-polluted soil to the heavy metals was Zn>Cr>Cu.It was concluded that the occurrence of chromate in the soil had a specific effect on the adsorption of Cu,Zn heavy metals,and that distinct linear correlation occurred between accumulative and desorptive quantity for Cu,Zn species in both soils,and that accumulative and desorptive quantities for the Cu,Cr species significantly increased exponentially.The annual mean desorptive chromium-species quantities from the soils were 127 and 104 times more than those soil of National Standard at pH4 and pH5 respectively under the action of simulated acid-rain,i.e.,the acid-rain accelerated the increase of the desorptive chromium species in chromate-polluted soil,therefore more potentially hazardous effect of chromium species was developed directly or indirectly.更多还原