茶园土壤有效态镉的提取方法  

Extraction method of available cadmium in tea garden soil

作　　者：李海涛 杨柳 方丽[1] 倪康[1] 石元值[1] LI Haitao;YANG Liu;FANG Li;NI Kang;SHI Yuanzhi(Tea Research Institute of Chinese Academy of Agricultural Sciences,Key Laboratory for Tea Plant Biology and Resource Utilization,Ministry of Agriculture and Rural Affairs,Hangzhou 310008,China;Graduate School of Chinese Academy of Agricultural Sciences,Beijing 100081,China)

机构地区：[1]中国农业科学院茶叶研究所,农业农村部茶树生物学与资源利用重点实验室,杭州310008 [2]中国农业科学院研究生院,北京100081

出　　处：《农业环境科学学报》2022年第1期75-83,共9页Journal of Agro-Environment Science

基　　金：国家茶产业技术体系项目(CARS-19);中国农科院协同创新任务项目(CAAS-XTCX2016015);中国农业科学院科技创新工程项目(CAAS-ASTIP-2016-TRICAAS)。

摘　　要：为筛选出适合茶园土壤有效态镉提取的提取剂并对提取方法进行优化,采集云南省普洱市、浙江省丽水市及嵊州市共62份土壤样品及其对应的茶树新梢样品,分别比较了0.1 mol·L^(-1)CaCl_(2)、0.1 mol·L^(-1)HCl、1 mol·L^(-1)NH;OAc、1 mol·L^(-1)MgCl_(2)、0.005 mol·L^(-1)DTPA 5种提取剂的提取效果,并对提取剂浓度、土液比、提取时间和振荡频率4个因素进行对比优化。结果表明:不同提取剂的提取率依次为0.1 mol·L^(-1)HCl>1mol·L^(-1)MgCl_(2)>0.005 mol·L^(-1)DTPA>0.1mol·L^(-1)CaCl_(2)>1 mol·L^(-1)NH;OAc。不同提取剂提取的有效态镉含量与新梢镉含量的相关系数从高到低依次为1 mol·L^(-1)NH;OAc>0.1 mol·L^(-1)CaCl_(2)>0.1 mol·L^(-1)HCl>1 mol·L^(-1)MgCl_(2)>0.005 mol·L^(-1)DTPA。提取条件优化试验发现,提取剂浓度和提取时间对有效态镉提取率影响较大,振荡频率和土液比对有效态镉提取率影响较小。研究表明,以NH;OAc作为茶园土壤有效态镉提取剂,提取参数为提取剂浓度6 mol·L^(-1)、土液比1∶10、提取时间120 min、振荡频率180 r·min;时,提取效果最佳。Precise determination of available cadmium in tea plantation soil is of great significance for risk assessment of the cadmium content in tea shoots and remediation of contaminated soil. To select a suitable extractant for available cadmium in tea plantation soil and to optimize the extraction method, 62 soil samples and relevant tea shoot samples were collected from Pu′ er, Lishui, and Shengzhou. The extraction effects of five extractants, namely 0.1 mol·L^(-1)CaCl_(2), 0.1 mol·L^(-1)HCl, 1 mol·L^(-1)NH;OAc, 1 mol·L^(-1)MgCl_(2), and 0.005 mol·L^(-1)DTPA were compared. We then compared and optimized four factors, namely the extractant concentration, ratio of soil to solution,extraction time, and oscillation frequency. The results showed that the extraction rate of different extractants was 0.1 mol·L^(-1)HCl>1 mol·L^(-1)MgCl_(2)>0.005 mol·L^(-1)DTPA>0.1 mol·L^(-1)CaCl_(2)>1 mol·L^(-1)NH;OAc. The correlation coefficient between the available cadmium content and tea shoot cadmium content was in the order of 1 mol·L^(-1)NH;OAc>0.1 mol·L^(-1)CaCl_(2)>0.1 mol·L^(-1)HCl>1 mol·L^(-1)MgCl_(2)>0.005 mol·L^(-1)DTPA. The extractant concentration and extraction time had a significant influence on the extraction efficiency of available cadmium,whereas the oscillation frequency and ratio of soil to solution had less influence. The results showed that NH;OAc was the best extractant of available cadmium in tea plantation soil. The best extraction conditions were 6 mol·L^(-1)NH;OAC, 1∶10 ratio of soil to solution, 120 min extraction time, and 180 r·min;oscillation frequency.

关 键 词：茶 土壤 有效态镉 提取剂 方法优化 

分 类 号：X53[环境科学与工程—环境工程]