土壤中有效态镉提取条件探讨

用４种提取剂在不同温度、时间和土液比条件下，对褐土有效态镉含量分别进行提取试验。结果表明，温度对提取镉量未产生明显影响，随提取时间延长和土液比减小，提取镉量有逐渐增加趋势。提取率（提取能力）随土壤镉污染加重（ＣａＣｌ２除外）和土液比的减小，有增加趋势。对提取镉量与油菜茎叶中镉含量所作相关研究表明，选用１ｍｏｌ／ＬＮＨ４ＯＡｃ提取褐土有效态镉较为适宜

THE CONDITION OF EXTRACTING AVAILABLE Cd FROM SOIL

The available Cd in the soil was extracted by using four kinds of extracting solvent at different temperature,time and ratio of soil to solvent.It showed that the temperature had not significant effect on extracting Cd,the contents of extracted Cd increased with the extracting time prolonged and the ratio of soil to solvent cut down.The extracted ability had the increasing tendency with the Cd pollution increased (CaCl 2 was excluded)and the ratio of soil to solvent cut down.It was concluded that,l mol/L NH 4OAc was suited for extracting the available Cd from soil by comparing the extracted Cd contents with the soil and Cd contents in the stem and leaves of rapes.