Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, Key Laboratory of Plant-Soil Interactions of the Ministry of Education, College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, People's Republic of China.
Institute of Landscape and Plant Ecology, University of Hohenheim, 70599, Stuttgart, Germany.
Environ Pollut. 2021 Apr 15;275:116623. doi: 10.1016/j.envpol.2021.116623. Epub 2021 Feb 2.
The cadmium (Cd) activity in soil has been widely studied. However, the interactive effects of soil properties (e.g. soil pH, CEC, and SOM) on Cd transfer from soil to grain are generally overlooked. In total 325 datasets including soil pH, CEC, SOM, and soil Cd content were used in this study. The descriptive statistics indicated that Cd content in wheat and maize soils ranged from 0.05 to 10.31 mg/kg and 0.02-13.68 mg/kg, with mean values of 0.87 and 1.14 mg/kg, respectively. Cd contents in wheat and maize grains were 0.01-1.36 mg/kg and 0.001-1.08 mg/kg with average values of 0.15 and 0.10 mg/kg, respectively. The results of SEM demonstrated that the interactive effects of soil properties contributed more to Cd transfer from soil to wheat grain than the soil Cd content. Subsequently, CITs-MLR indicated that the critical factors, including soil pH and total soil Cd content, could mask the contribution of other soil properties on Cd accumulation in grain; soil CEC may prevent Cd from leaching and therefore improve grain Cd level of wheat especially at acidic soil condition. The result of derived Cd thresholds revealed that current Cd thresholds are not completely suitable to wheat and maize grain at different soil conditions. This study provides a new model for further investigation on relationships between soil properties, soil Cd content and grain Cd level.
土壤中镉（Cd）的活性已得到广泛研究。然而，土壤性质（如土壤 pH 值、CEC 和 SOM）对 Cd 从土壤向谷物转移的相互作用影响通常被忽视。本研究共使用了 325 组包括土壤 pH 值、CEC、SOM 和土壤 Cd 含量的数据。描述性统计数据表明，小麦和玉米土壤中的 Cd 含量范围分别为 0.05-10.31mg/kg 和 0.02-13.68mg/kg，平均值分别为 0.87mg/kg 和 1.14mg/kg。小麦和玉米籽粒中的 Cd 含量分别为 0.01-1.36mg/kg 和 0.001-1.08mg/kg，平均值分别为 0.15mg/kg 和 0.10mg/kg。SEM 结果表明，土壤性质的相互作用对 Cd 从土壤向小麦籽粒转移的影响大于土壤 Cd 含量。随后，CITs-MLR 表明，包括土壤 pH 值和土壤总 Cd 含量在内的关键因素可能掩盖了其他土壤性质对籽粒 Cd 积累的贡献；土壤 CEC 可能会阻止 Cd 淋失，从而提高小麦特别是在酸性土壤条件下的籽粒 Cd 水平。衍生 Cd 阈值的结果表明，目前的 Cd 阈值不完全适用于不同土壤条件下的小麦和玉米籽粒。本研究为进一步研究土壤性质、土壤 Cd 含量和籽粒 Cd 水平之间的关系提供了一种新的模型。
