摘要
【目的】探索土壤环境中不同污染浓度的重金属镉(Cd)、汞(Hg)、铜(Cu)和铅(Pb)对荸荠生长的影响及空间分布规律,为荸荠的安全种植及合理布局提供理论支持。【方法】以广西主要荸荠品种桂蹄2号为研究对象,分别进行不同污染浓度的镉、汞、铜和铅的盆栽试验,设0、0.25、1、1.75、2.5 T(T为每个重金属土壤环境限量值)5个添加量浓度,土壤中重金属浓度为添加量浓度+试验土壤本底浓度。在荸荠成熟后,分析荸荠果肉、皮和茎叶中各元素分布及富集积累规律。【结果】荸荠在不同浓度的各重金属处理下均能正常生长,吸收重金属元素特征分别为:铜、铅和镉在不同部位含量分布为:茎叶>皮>果肉;汞分布为:皮>果>茎叶。荸荠中不同部位重金属的含量随着土壤中重金属含量的增加而增加。在0.25 T汞处理下和2.5 T铅处理下,荸荠果肉中汞和铅的含量分别超过《食品安全国家标准食品中污染物限量》(GB2762-2017)中新鲜蔬菜水果的限量值。【结论】低浓度重金属的处理会促进荸荠产量的提高,荸荠各部位对重金属吸收累积具有显著的分布规律:镉、铅和铜元素地上茎叶植株吸收多,块茎吸收少,汞则相反;荸荠对铅和镉耐受性强,在土壤达到环境限量值时,荸荠果肉中铅和镉含量符合标准要求;汞容易被荸荠吸收,在有汞污染风险的区域建议不要种植。
【Objective】To provide the theory reference for safe planting and layout of water chestnut,the influence of different contents of heavy metal Cu,Pb,Cd and Hg on the growth of water chestnut and its spatial distribution law in soil environment were explored.【Method】Based on the main growing varieties of water chestnut in Guangxi province,the pot experiment of different pollution levels of heavy metal including Cu,Pb,Cd and Hg were carried out.Five levels 0,0.25,1,1.75 and 2.5 T(T stands for the limit of Cu,Pb,Cd and Hg in soil environmental)were set respectively.So the concentration of heavy metals in the soil is equal to the sum of adding concentration and background concentration.The distribution and accumulation of four heavy metal elements in flesh,peel and stem leaves were analyzed after water chestnuts matured.【Results】The water chestnuts grew normally under heavy metal contamination,the absorption characteristics of Cu,Cd and Pb were stem leaf>peel>pulp.The distribution of Hg in water chestnut was peel>pulp>stem leaf.The concentration of elements of Cu,Pb,and Hg in all parts of the water chestnut increased with the concentration of heavy metal elements in the soil.Under the treatments of 2.5 T of Pb and 0.25 T of Hg,the edible part of water chestnut exceeded the limit value of fresh fruits and vegetables according to the GB2762-2017.【Conclusion】The low concentration of heavy metal will promote the increase of the production of water chestnut.There were significant laws for distribution of heavy metal in various parts of water chestnut,the contents of Cu,Pb,and Cd of the stem and leaf were higher than the tuber in the water chestnut,but the content of Hg was the opposite.Water chestnut had a strong tolerance to Pb and Cd.In the condition of the environmental limit of Pb and Cd in the soil,the contents of Pb and Cd in the pulp met the standard requirements.Hg was easily absorbed by the water chestnut and it is advised not to be planted in areas where there is a risk of Hg pollution.
作者
谢丽萍
李焘
蒋翠文
王彦力
牙禹
韦宇宁
何洁
闫飞燕
XIE Li-ping;LI Tao;JIANG Cui-wen;WANG Yan-li;YA Yu;WEI Yu-ning;HE Jie;YAN Fei-yan(Institute for Agricultural Product Quality Safety and Testing Technology,Guangxi Academy of Agricultural Sciences,Guangxi Nanning 530007,China)
出处
《西南农业学报》
CSCD
北大核心
2018年第8期1712-1716,共5页
Southwest China Journal of Agricultural Sciences
基金
广西农科院优势学科团队项目(桂农科2015YT94)
广西农业科学院科技发展基金项目(桂农科2017JM57)
广西农业科学院科技发展基金项目(桂农科2017JM63)
关键词
荸荠
重金属
富集
质量安全
Water chestnut
Heavy metals
Enrichment
Quality and safety
