【摘要】 为探索裸土起尘颗粒物中铅、镉的化学形态与矿物的赋存关系,通过采用铅、镉元素对土壤样品进行模拟污染并老化处理,在一定风速条件下进行实验,对模拟污染土壤的吹前表层土、总悬浮颗粒物(TSP)、吹后表层土中矿物组成、含量与重金属铅、镉的化学形态进行分析,同时重点探讨颗粒物中铅、镉的化学形态与矿物的关系。结果表明:裸土起尘颗粒物中铅的碳酸盐结合态所占比例最高,在44.28%～53.05%之间,镉的可交换态所占比例最高,在59.07%～75.9%之间;不同类型尘中矿物组成基本相同,其中黏土矿物(伊利石和绿泥石)所占比例较大,吹前表层土中为66.3%,起尘后的悬浮颗粒物中为85.1%;不同类型尘中碳酸盐结合态铅、可交换态镉含量与黏土矿物含量变化规律呈正相关。黏土矿物含量变化可能是导致裸土起尘颗粒物中铅、镉化学形态变化的主要因素。更多还原

【Abstract】 In order to explore the relationship between the chemical morphology of lead and cadmium in dust particles of bare soil and the occurrence of minerals,the soil samples were subjected to pollution simulation and aging treatment by using lead and cadmium,and the experiment was carried out under a certain wind speed.The mineral composition and content of the surface soil before blowing,total suspended particulate matter(TSP),and the heavy metals lead and cadmium in the surface soil after blowing were analyzed.The relationship between the chemical forms of lead and cadmium in particulate matter and minerals was discussed.The results showed that proportion of lead carbonate binding state in the dust particles of bare soil is the highest,between 44.28% and 53.05% and that of cadmium exchangeable state was the highest,between 59.07% and 75.9%.The mineral composition of different types of dust is basically the same,among which clay minerals(illite and chlorite)account for a large proportion,66.3% in the topsoil before blowing,and 85.1% in the suspended particles after dusting.The content of carbonate bonded lead and exchangeable cadmium in different types of dust is positively correlated with the content of clay minerals.The changes of clay minerals may be the main factors leading to the changes of chemical forms of lead and cadmium in the dust particles of bare soil.更多还原