Research On Heavy Metal Pollution And Bioavailability Of Vegetable Garden Soils In Hefei City Suburbs

The environment human lived had been influenced tremendously while huge profits were brought to us along with the process of industrialization.They threaten the survival of mankind through various channels when they came into being,Heavy metal pollution is one of them.To be the important residence,city has being polluted by the heavy metals,heavy metals endangered human' healthy including direct ways,such as dust,at the same time,various indirect influence becoming seriously day by day.The soil heavy metal pollution and the vegetable pollution had caused more and more attention.This paper investigated and tested the contents of heavy metals in garden soils and vegetables on the NanFeihe river(including 32 soil samples and six varieties of vegetables),from the statistical analysis of the test data,give the description qualitatively and quantitatively,get the information of heavy metal pollution of the garden soils and the vegetables,get the statistical relationships between contents in vegetables and entire contents,available contents in soils of heavy metals,calculate the absorption coefficients and give proposals pertinently.The results were as follows:1.Compared to the contents of heavy metals to the background values of the Nation, the order is:Zn＞Pb＞Cu＞Cd＞Cr.2.Look into the synthetic pollution indexes of 32 soil samples,there have 53 percents under the safe level,nine points were in low-grade pollution level,no one found been polluted.There have four elements not been polluted,the synthetic pollution indexes of the heavy metals in the order of Cd＞Zn＞Cu＞Pb＞Cr.3.Correlation analysis indicated that entire contents of heavy metals have significant or high-significant positive correlations among each others.Only Cr has not found the significant correlation when analyzed the contents between entire contents and available contents of the five heavy metals.4.Analyzed the contents(total,available) of heavy metals between garden soil and vegetables,the available contents had more obviously significant correlation to the contents in vegetables than the total contents of heavy metals. 5.Vegetables had been polluted by Pb,Cd,Cr,rates of exceeding standard of Pb is the highest.Look at the average pollution indexes,the average pollution indexes of Pb exceed 1 only,there only one kind was below 1 among six varieties of vegetables;the pollution index of Cu is the smallest in the five indexes investigated.6.The synthetic pollution indexes of six varieties vegetables were in the order of cabbage＞shallot＞celery & eggplant＞leek＞beanstalk,the biggest is 0.78,the lowest is 0.3.7.The concentrating ratio of Cd was the highest among the five elements,the concentrating ratio of Cd of the six vegetables was in the order of leek＞celery＞shallot＞cabbage＞eggplant＞beanstalk.Through the analysis of the experiment results,there have some suggestions to vegetables cultivation in the city suburbs of Hefei:far away from sources of pollution; reduce the entrance of heavy metals in the process of vegetable cultivation;to the area polluted,change the planting mode reasonably and take the measures effectively are essentially.