摘要
为了解施用不同种类改良剂对降低矿区土壤重金属移动性的长期效果,进行为期6年的模拟试验,用化学提取方法评价磷灰石、农用石灰、坡缕石、钙镁磷肥、沸石、猪粪和水稻秸秆7种常用改良剂对降低土壤重金属溶解性的影响。结果表明,农用石灰、钙镁磷肥、磷灰石、坡缕石和沸石对降低矿区土壤水溶态重金属均有良好的效果,但猪粪和水稻秸秆有机物改良剂的效果较差。降低土壤水溶态Cd的效果以钙镁磷肥为最佳(平均可降至29%),降低土壤水溶态Cu的效果以坡缕石为最佳(平均可降至65%),降低土壤水溶态Pb的效果以磷灰石、石灰和钙镁磷肥3种改良剂为佳(平均可降至27%左右);降低土壤水溶态Zn的效果以钙镁磷肥为最佳(平均可降至48%)。磷灰石和沸石对土壤重金属的稳定性有较长的作用效果,坡缕石、石灰和钙镁磷肥对土壤重金属稳定性随试验时间增加有明显的下降;有机物类改良剂对土壤重金属的稳定效果较差,且随有机物质的降解,其稳定效果显著下降。
The use of seven amendments as potential immobilizers of heavy metals in a mine contaminated soil has been studied by monitering water solublity of the heavy metals for six years.The 0.01 mol/L calcium chloride extractions was applied to measure the solubility of heavy metals in the soil.The tested amendments were agricultural limestone,rock phosphate,palygorskite,calcium magnesium phosphate,zeolite,pig manure,and straw.Treatments of 5 mineral materials,including agricultural limestone,rock phosphate,palygorskite,calcium magnesium phosphate,and zeolite,reduced greatly the water soluble metals in the soil,whereas treatments of pig manure and straw were less effective in reducing the water soluble heavy metals in the soil.The most suitable amendments in decreasing water solublity of the metals in the soil were calcium magnesium phosphate for Cd,palygorskite for Cu,calcium magnesium phosphate for Zn,agricultural limestone,rock phosphate and palygorskite for Pb.Both rock phosphate and zeolite were long-term effective amendments for reducing the solubility of soil heavy metals.The long-term effects of agricultural limestone,palygorskite,and calcium magnesium phosphate in reducing the solubility of heavy metals in the soil were less than those of rock phosphate and zeolite,and the effects decreased with the increase of experiment time.The effects for organic amendments were comparatively weak and decreased gradually with increasing decomposition of the added organic matter.
出处
《水土保持学报》
CSCD
北大核心
2012年第5期144-148,共5页
Journal of Soil and Water Conservation
基金
国家自然科学基金项目(40771090,40471064)
关键词
矿区污染土壤
重金属
改良剂
水溶性
mine contaminated soil
heavy metals
amendment
water solubility
