果树学报2017，Vol.34Issue(4)：473-481,9.DOI:10.13925/j.cnki.gsxb.20160180
浙江地区杨梅园土壤重金属含量变异特征与污染风险评价
Heavy metals in soils and assessment of environmental risk in Myrica rubra plantations in Zhejiang province
摘要
Abstract
[Objective]Myrica rubra is a subtropical tree grown for its sweet,crimson to dark purple-red,edible fruit,which is very populous in China.It is native to eastern Asia,mainly in south-central China,where the tree has been cultivated for at least 2 000 years.Due to the high medicinal and edible values of M.rubra,the planting area of the fruit has exceeded 5 million acres in China including 1.3 million acres in Zhejiang province.With people' s concerns about the healthiness of the diet,increasing attention is being paid upon the production environment and fruit quality and safety of M.rubra.Heavy metal content in M.rubra soil is an important parameter for the safety of the product.In this study,the contents of six heavy metals in soils sampled from orchards in Taizhou,Wenzhou,Shaoxing and other places of Zhejiang province were investigated.The aim was to provide a reference for the evaluation and management of soils and environmental quality in the traditional M.rubra producing regions in China.[Methods]Two hundred and forty-one soil samples were collected from the M.rubra producing areas in Zhejiang province from 2007 to 2013.Soils were sampled from a depth of 0-40 cm,and each sample volume was 1 kg evenly composed of soils sampled from five sites randomly selected from M.rubra orchards.The Pb,Cd,Cu,Zn and Cr contents were detected with an atomic absorption spectrophotometer and As and Hg contents were detected using an atomic fluorescence spectrometer.Correlation analysis was carried out to reveal the relationships between heavy metals.The assessment of heavy metal pollution in the orchards was conducted using single pollution index and comprehensive pollution index methods.[Results] The average contents of heavy metals in the soil samples from the M.rubra plantations were in the order of Zn＞ Cr＞ Pb＞ Cu＞ As＞ Hg＞ Cd.The contents of Hg,As,Pb and Zn in some soil samples exceeded the limits.In case of Hg,there was only one sample with 0.21 mg kg-1,which was slightly higher than the limit of 0.20 mg kg-1.The contents of As in 6 soil samples were slightly higher than the limit.The Pb contents in 18 soil samples collected mostly in 2007 and 2008 were higher than the current limit of 45 mg kg-1.In addition,20 soil samples had a Zn content that exceeded the limit value of 100 mg kg-1.The majority of heavy metals in the M.rubra soils showed a slow deceasing trend from 2007 to 2013.Correlation analysis of heavy metals and pH value in the soils showed that there was no significant correlation between Hg and other elements.The content of Cu showed significant positive correlations with As,Zn,Cd and Cr.There was a positive correlation between Pb and Cd as well as between Cr and As (P＜O.001).However,a significant negative correlation was found between pH and As and between pH and Cr.Except for Hg,As,Pb and Zn in a few of the soil samples,the heavy metal contents in most of the soil samples were lower than the limits of the soil environment quality standard.Soil samples were also assessed by means of the single factor pollution index method and the comprehensive pollution index method.The result showed that the highest single factor pollution index was found in Pb in soil samples collected in 2008,which was 0.90.For most of the years (except for 2009 and 2012),the pollution index of Zn was higher than 0.70,which was below the limit for food safety.However,the single factor pollution indexes of the heavy metals were all lower than 1.0,and so was the comprehensive pollution index.[Conclusion]Although some soil samples contained heavy metals exceeding the limits,the pollution index showed low risk of heavy metal pollution in the soils of M.rubra plantations in Zhejiang province.However,the pollution index of zn was always on the alert level,which needs to be further studied with the method of source apportionment.Policy of source control and prevention should be adopted to control heavy metal pollution in M.rubra plantations.关键词
杨梅/果园/土壤/重金属/风险评价Key words
Myrica rubra/Orchard/Soil/Heavy metal/Risk assessment分类
农业科技引用本文复制引用
吕豪豪,梁森苗,刘玉学,江波,吕爱华,钟哲科,杨生茂..浙江地区杨梅园土壤重金属含量变异特征与污染风险评价[J].果树学报,2017,34(4):473-481,9.基金项目
公益性行业(农业)科研专项(201203089) （农业）
浙江省科技计划项目(2015C03020) （2015C03020）
国家国际科技合作项目(2014DFE90040) （2014DFE90040）
