清水河地段黄河悬沙表层沉积物中重金属本底值测定

DETERMINATION OF HEAVY METAL BACKGROUND VALUE IN THE SUPERFICIAL COAT SEDIMENT OF THE YELLOW RIVER SECTION IN QINGSHUIHE AREA

按不同浓度盐酸、不同浸取时间来解吸不同粒度的黄河悬沙表层沉积物中的重金属，并用原子吸收分光光度计测定铜、锌、铅、镉的吸附量．实验表明：镉极少吸附于表层沉积物中；铅的吸附本底值不随沉积物粒度变化而改变；铜、锌被吸附的本底值随沉积物粒度变小而增大．此外，浸取酸度和浸取时间对重金属的解吸影响很小．

Hydrochloric acid of different concentration has been used for different leaching time to desorb heavy metals from the superficial coat sediment with different granularity of the Yellow River suspended solid.An atomic absorption spectrophotometer has been used to determine the absorption of Cu,Zn,Pb and Cd.Tests show that little Cd is absorbed in the superficial coat sediment,and the background value of Pb does not vary with the granularity of the sediment.However,that of Cu and Zn increases with the reduction of sediment granularity.Besides,it has been shown that the leaching acidity and time exert quite a small influence on the desorption of heavy metals.This paper will help to understand the diversion and destination of heavy metals in the Yellow River.