Migration and enrichment characteristics and its influencing factors of germanium in soil-tea system
A total of 1478 surface soil samples,10 groups of soil vertical profiles,130 groups of tea and root soil samples were collected from the tea garden in Xianfeng County,western Hubei Province.The contents of germanium(Ge),major oxides,organic carbon(Corg)and pH value in the soil,as well as the contents of Ge and heavy metals in the roots,stems and leaves of tea trees were measured to study the migration and transformation of Ge in soil-tea trees and its influencing factors.The results showed that the average Ge concentration in tea soil was 1.56 mg/kg,which was higher than the mean abundance of 1.30 mg/kg in China.The vertical distribution of soil content generally showed an increasing trend with the increase of depth.The average Ge content in tea was 5.56 μg/kg and ranged from 1.76 to 28.00 pg/kg.According to the Ge content and bioconcentration factor,different parts of tea plant were ranked as:roots＞stems＞old leaves＞tender leaves,and translocation factor ranked as:tender leaves＞old leaves＞stems.The correlation analysis showed that low pH and abundant organic carbon were beneficial for the enrichment of Ge in surface soil(≤ 50 cm),but had the opposite effect on deep soil(＞50 cm).There was a significant negative correlation between soil Ge and SiO2 content,and a sig-nificant positive correlation with A12O3 content,which may be affected by the adsorption of clay minerals.Weakly ba val-ue of soil and strong desilicified allitization were beneficial for the Ge enrichment of soil.Low pH,strong ba value of soil,and weak desilicified allitization were beneficial for tea plant to absorb Ge of soil in tea garden.The transfer of Ge in vari-ous parts of tea plants was highly positively correlated with arsenic.
万方数据
维普
