Characteristics and Source Analysis of Heavy Metal Accumulation in Different Soil Types of the Yarlung Zangbo River Basin
To understand different types of soil heavy metal content,distribution,pollution degree and source analysis of Yarlung Zangbo River Basin,21 sampling points were set in farmland and woodland of Lang County-Milin,and a total of 126 soil samples were collected to analyze the soil heavy metal content,distribution,pollution degree and the difference of pollution source.The results show that the mean content of Cd elements in farmland and forest soil in the Yarlung Zangbo River Basin exceeded the background value of Tibetan soil,and the mean Cd content in farmland soil was higher than that of woodland soil,and the mean content of Cr,Co,Ni,Cu,Zn,As,Pb and Sb did not exceed the background value of Tibetan soil.There is a significant difference of Co,Ni,Zn,As,and Cd content in farmland and woodland(P＜0.05).The content of heavy metal elements in the soil of farmland and woodland shows a segmented spatial distribution pattern.The land accumulation index of Cd elements in farmland soil is higher than that of woodland soil.The potential ecological risk index results indicate that farmland and woodland are at moderate and low ecological risk levels,respectively.Cd element is the main risk factor that causes the potential ecological risk and harm of farmland and woodland.Heavy metals in farmland soil mainly come from transportation sources(43.05％),natural sources(31.32％)and mixed sources of natural and agricultural activities(25.63％).Heavy metals in woodland soil mainly come from transportation sources(44.29％),natural sources(34.79％)and mixed sourc-es of natural and domestic waste(20.92％).
Yarlung Zangbo River Basinsoilheavy metalspollution evaluationsource analysis
万方数据
维普
