山东济宁金乡大蒜产地重金属在土壤—农作物中迁移转化特征研究

Study on Characteristics of Heavy Metal Elements in Topsoil and Crops in Jinxiang Garlic Producing Area

摘要:

基于金乡县南部地区土地质量地球化学调查与评价项目，系统采集表层土壤和大蒜样品，对As、Cd、Cr、Cu、Hg、Ni、Pb、Zn共8种重金属元素全量及形态数据进行深入分析，研究发现，土壤重金属形态除Cd、Hg外以残渣态占绝对优势；重金属生物可利用系数与SOM、pH、CEC均呈负相关；大蒜植株不同部位对元素的富集特征具有明显差异性，As、Cd、Cr、Pb、Ni、Cu、Zn表现为须根＞叶身＞假茎＞蒜头；蒜头Cd与土壤Cd全量呈显著性正相关，其余元素与对应土壤中全量相关关系不明显。

Abstract:

Based on the results of geochemical survey and evaluation of land quality，the morphological characteristics of heavy metal elements in surface soil and garlic samples have been obtained, Through in-depth analysis of the total amount and speciation data of eight heavy metal elements, including As, Cd, Cr, Cu, Hg, Ni, Pb and Zn, it is found that the residue form of soil heavy metal is the dominant form except Cd and Hg. The bioavailability coefficient of heavy metals is negatively correlated with SOM, pH and CEC; The enrichment characteristics of elements in different parts of garlic plants are obviously different. As, Cd, Cr, Pb, Ni, Cu, Zn are fibrous root>leaf body>pseudostem>garlic. There is a significant positive correlation between garlic Cd and the total amount of soil Cd, while the correlation between other elements and the total amount of corresponding soil Cd is not significant.