川芎镉污染现状调查及原因分析

Investigation and analysis of cadmium pollution in Chuanxiong

目的:本文通过文献研究、实地调研、问卷调查及对30批川芎进行重金属镉含量测定,以评价川芎镉污染现状,并对影响川芎镉含量的因素进行分析。方法:查阅影响川芎镉污染原因的相关文献,并对四川省内3家药企、5家药材市场、10家川芎合作社、4县11镇11村开展实地调研与问卷调查,收集眉山、彭山、都江堰、什邡、彭州五地不同苓种来源的川芎药材及对应根际土壤,综合考察了土壤pH值及镉含量,以及川芎苓种类型、栽培中使用的农投品对川芎药材镉含量的影响。结果:文献表明,土壤生物及理化特性和川芎的药学特性是影响川芎中镉元素含量的主要因素;实地调研结果表明,川芎种植户及经销商对川芎镉超标问题缺乏重视;实验结果表明,传统产区的土壤镉背景值在不断增加,土壤酸化问题严重;此外,山苓种培育出的川芎镉含量低于坝苓种。结论:土壤镉总量和有效态含量是衡量镉污染川芎外部环境因素的主要指标,种质与内生菌群是决定川芎镉污染最主要的内部因素;调查地内川芎土壤镉背景值均严重超标(国家土壤二级标准≤0.30mg/kg),引发对川芎适宜生态区划的思考;下一步应对川芎富集重金属的生物机制、与镉吸收存在竞争性抑制作用的元素含量以及土壤栽培年限对川芎富集镉的影响程度深入研究。

Objective:Through literature research,field investigation,questionnaire survey and determination of heavy metal cadmium content in 30 batches of Chuanxiong,this paper evaluated the cadmium pollution status of Chuanxiong and analyzed the factors affecting the cadmium content.Method:The relevant literature on the causes of cadmium pollution in Chuanxiong were consulted.Field research and questionnaire survey were carried out in 3 pharmaceutical companies,5 medicinal materials markets,10 Chuanxiong cooperatives,4 counties,11 towns and 11 villages in Sichuan Province.The medicinal materials of Chuanxiong from different cultivars in Meishan,Pengshan,Dujiangyan,Shifang and Pengzhou were collected,and the corresponding rhizosphere soil was comprehensively investigated.The effects of soil pH value,cadmium content,species type of Chuanxiong and agricultural products used in cultivation on cadmium content of Chuanxiong were investigated comprehensively.Result:The literature showed that the biological and physicochemical properties of soil and the pharmaceutical properties of Chuanxiong were the main factors affecting the content of cadmium in chuanxiong.The results of field investigation showed that farmers and dealers did not pay much attention to the problem of cadmium exceeding the standard of Chuanxiong.The experimental results showed that the background value of cadmium in soil in traditional producing areas was increasing,and the problem of soil acidification was serious.In addition,the cadmium content in Chuanxiong cultivated in mountain was lower than that of flat-growing.Conclusion:The total amount and available content of cadmium in soil are the main indexes to measure the external environmental factors of Chuanxiong.The germplasm and endophytic bacteria are the main internal factors to determine the cadmium pollution of Chuanxiong.The background value of cadmium in the cultivation soil of Chuanxiong exceed the standard of the second level of the national soil standard(≤0.30mg/kg),which lead to the consideration of the appropriate ecological regionalization of Chuanxiong.The next step should be to further study the biological mechanism of heavy metal enrichment in Chuanxiong,the content of elements that have competitive inhibiting effect on cadmium absorption and the degree of influence of soil cultivation years on the enrichment of cadmium in Chuanxiong.