Relationships between soil properties and toxicity of copper and nickel to bok choy and tomato in Chinese soils

National Soil Fertility and Fertilizer Effects Long-term Monitoring Network, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, China
Environmental Toxicology and Chemistry (Impact Factor: 2.83). 10/2013; 32(10). DOI: 10.1002/etc.2312
Source: PubMed

ABSTRACT The toxicity of copper (Cu) and nickel (Ni) to bok choy and tomato shoot growth was investigated in a wide range of Chinese soils with and without leaching with artificial rainwater. The results showed that the variations of Ni toxicity induced by soil properties were wider than that of Cu toxicity to both tomato and bok choy plant growth. Leaching generally decreased the toxicity of Cu and Ni added to soils, which also depended on soils, metals and test plant species. Soil factors controlling metal phytotoxicity were found to be soil pH and soil organic carbon content for Cu, and soil pH for Ni. It was also found that soil pH had stronger effects on Ni toxicity, compared to Cu toxicity. Predictive toxicity models based on these soil factors were developed. These toxicity models for Cu and Ni toxicity to tomato plant growth were validated using an independent dataset using European soils. These models could be applied to predict the Cu and Ni phytotoxicity in not only Chinese, but also European soils. Environ Toxicol Chem © 2013 SETAC.

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