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The Study Of Vegetables Heavy Metal Content And Accumulation Model Based On Different Production Areas In Zhejiang Province

Posted on:2018-12-29Degree:MasterType:Thesis
Country:ChinaCandidate:X BaoFull Text:PDF
GTID:2371330548981672Subject:Agricultural extension
Abstract/Summary:PDF Full Text Request
Vegetable is indispensable for daily human food consumption,which provides the necessary dietary fiber and vitamins for the human body.With the rapid development of industrialization and urbanization in Zhejiang,a representative of China economy developed province,heavy metal pollution is become more and more serious threats.The heavy metals may bioaccumulate into the human body from a variety of sources-vegetables system,that ultimate threats to human health.Therefore we should pay more attention to the environment and food safety problems caused by heavy metal pollution.So it is important to start the research of the heavy metal in vegetables of Zhejiang province.Based on it,we can guide the vegetables clean production and safety consumption,promote the healthy development of vegetable industry to supply vegetables and risk assessment of heavy metals.Three plains of Zhejiang province,northern plain,eastern plain and middle plain and 12 cities from the 3 plains were researched.Radish,lettuce,green vegetables,broccoli and tomatoes are the representative of five kinds of vegetables,root,stem,leaf,flower,fruit vegetables.The collection of the vegetables and soil samples is 498 in total.Analysis of 5 heavy metals As,Cd,Cu,Pb,Zn.The determination of soil physical and chemical properties and the state of heavy metal effectively were took at the same time.According to the relevant data,we set up five kind of vegetables for five kinds of heavy metal absorption models,25 models in total.And we put forward related solutions in order to reduce the vegetables for the absorption of heavy metals,promote the vegetable production safety.Main results and innovation points of this study are as follows:1.The average distribution of the soil heavy metal and characteristics in zhejiang province has grasped comprehensively.The average content of the 5 kinds of heavy metal As,Cd,Cu,Pb,Zn in the soil of Zhejiang province are 10.12mg/kg,0.44mg/kg,32.71mg/kg,34.10mg/kg,100.67mg/kg,.respectively.It indicates that the Cd was severe pollution accorrding to compared with the corresponding national standards,,The As and Pb was safety,Cu and Zn was light pollution.Heavy metal pollution degree is different in different areas.In the Northern Zhejiang province,the pollution of Cd was worst,and it was positively related with the economic development level,In the east area of Zhejiang province,Zn and Cu pollution problem was more outstanding compared with other areas.2.Different distribution are different for different heavy metals pollution of vegetable.About the 5 kinds of heavy metals As,Cd,Cu,Pb,Zn,the average content in radish were 0.0035mg/kg.0.0304mg/kg.0.4230mg/kg.0.0234mg/kg.3.3124mg/kg,the average content in lettuce were 0.0027mg/kg.0.0345mg/kg.0.6301mg/kg.0.0092mg/kg.1.6630mg/kg,the average content in Chinese cabbage were 0.0152mg/kg.0.0447mg/kg.1.1530mg/kg.0.1024mg/kg.6.3238mg/kg,the average content in cauliflower were 0.003 9mg/kg.0.0086mg/kg.0.8186mg/kg.0.0242mg/kg.4.4039mg/kg,the average content in tomato were 0.0035mg/kg.0.0249mg/kg.0.9544mg/kg.0.0255mg/kg.1.9294mg/kg,It is obvious that Chinese cabbage is the most easy to enrichment of heavy metals in the five kinds of vegetables.Five kinds of heavy metal,only the Cd in the case.The overproof rate of in radish,lettuce,Chinese cabbage,cauliflower were 12.8%,,14.3%,,30.9%,6.9%,and 0%,respectively..3.We study the heavy metal enrichment capability of the five kinds of vegetables.The results show that the enrichment coefficient of leaf vegetables are the highest.The strongest enrichment ability of As in five kinds of vegetables are Chinese cabbage,followed by cauliflower,radish,lettuce and tomato.The enrichment ability of Cd from strong to weak are Chinese cabbage,radish,lettuce,tomato,cauliflower.The enrichment ability of Cu from strong to weak are Chinese cabbage,cauliflower,tomato,lettuce,radish.The enrichment ability of Pb from strong to weak are Chinese cabbage,cauliflower,tomato,radish,lettuce.The enrichment ability of Zn in turn are Chinese cabbage,cauliflower,radish,tomato,lettuce.4.Vegetables heavy metal absorption model was established based on multiple regression analysis.The physical and chemical properties of the soil can affect the plant absorption of heavy metals.This study is to analyze the physical and chemical properties of soil,the soil heavy metal contents,absorbed content of vegetables.We want to establish a related vegetables for the absorption of heavy metal model,and analysis of vegetable's capacity of absorbing heavy metals from the soil.Because of the different types of vegetables and different kinds of heavy metal migration patterns has difference.This study established respectively between the five types of vegetables,five kinds of heavy metal,a total of 25 heavy metals from soil to vegetables migration model,The basic types and common heavy metal pollution could cover all kinds of vegetables.In conclusion,vegetables heavy metal content is closely related to the heavy metal content in soil and their physical and chemical properties.According to its absorption law establishing scientific planting management mode and the reasonable layout of production can effectively reduce the enrichment of heavy metals in vegetables,and ensure food safety and human health.This is the ultimate goal of this research and the value.
Keywords/Search Tags:heavy metal, soil, vegetable, enrichment, mathematical model
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