锑对甘蓝的毒性阈值研究

为丰富完善我国土壤中Sb（锑）对植物的毒理学数据并为土壤Sb生态基准的制定提供依据，参照国际标准化组织颁布的植物毒性试验的标准方法（ISO 11269-2:2013），以外源添加的方式研究了我国17种典型土壤中Sb对甘蓝早期生长生物量的影响.结果表明:①基于全量Sb推导的甘蓝的毒性阈值EC₁₀（10%抑制效应浓度）变化范围为100.55~656.65 mg/kg，表明不同土壤中Sb的毒性差异显著，但基于有效态Sb（Na₂HPO₄溶液提取）推导的不同土壤中EC₁₀的变化范围为8.28~24.05 mg/kg，其EC₁₀差异有所减小；②相关性分析表明，基于土壤全量Sb推导的EC₁₀与w（OM）（OM为有机质）、w（TN）（TN为全氮）和CEC（阳离子交换量）均呈显著正相关（相关系数为0.746~0.779），而基于有效态Sb推导的EC₁₀与w（Fe）和w（Mn）呈显著正相关（相关系数为0.479~0.615）；③多元回归分析进一步表明，土壤pH、w（OM）和CEC可以解释基于全量Sb推导的EC₁₀值74.6%的变异，w（OM）和w（Mn）可以解释基于有效态Sb推导的EC₁₀值62.6%的变异.研究显示，Sb的Na₂HPO₄提取态能在一定程度上解释不同土壤中Sb对甘蓝的毒性差异，pH、w（OM）、CEC和w（Mn）是影响Sb对植物毒性的土壤主控因子，可以较好地预测Sb的毒性阈值. 

Study on Antimony Toxicity Threshold of Cabbage

In order to enrich the toxicological data of Sb (antimony) on plants in Chinese soils and to provide a basis for the establishment of soil Sb ecological criteria, the effects of exogenous Sb on the early growth biomass of cabbage in 17 typical Chinese soils were studied by referring to the standard method of phytotoxicity testing (ISO 11269-2:2013) issued by the International Organization for Standardization. The results showed that: (1) According to the measured total Sb concentrations, the toxicity threshold EC₁₀(concentration causing 10% toxic effect) for the cabbage ranged from 100.55 to 656.65 mg/kg, indicating significant differences in toxicity in different soils. However, based on the bioavailable Sb extracted by Na₂HPO₄ solution, the EC₁₀ in different soils ranged from 8.28 to 24.05 mg/kg, and the difference in EC₁₀ was reduced. (2) Correlation analysis showed that based on the measured total Sb, EC₁₀ was significantly positively correlated with organic matter content, total nitrogen, and cation exchange capacity (correlation coefficients were 0.746-0.779). Based the bioavailable Sb, EC₁₀ was significantly positively correlated with Fe and Mn concentrations (correlation coefficients were 0.479-0.615). (3) Multiple regression analysis further showed that soil pH, organic matter content, and cation exchange capacity could explain 74.6% of the variance in EC₁₀ values based on the measured total Sb, and the organic matter and Mn concentrations could explain 62.6% of the variance in EC₁₀ values basing the bioavailable Sb. This study showed that to some extent, the Na₂HPO₄-extracted Sb could explain the differences in the toxicity of Sb to cabbage in different soils. Soil pH, organic matter content, cation exchange capacity and Mn concentrations were the main soil factors influencing phytotoxicity of Sb, and could better predict the toxicity threshold of Sb.