In Situ Remediation of Nickel Phytotoxicity for Different Plant Species

Abstract

Acidic nickel (Ni)-contaminated soils in the vicinity of a Ni refinery at Port Colborne (Ontario, Canada) cause Ni phytotoxicity and require remediation. Thus, a greenhouse test with 11 plant species with a wide range of susceptibility to Ni toxicity was conducted to determine if Ni phytotoxicity of all species could be ameliorated by a high rate of limestone. At the original pH of 5.2, the Welland soil (Typic Epiaquoll; 2900 mg kg⁻¹ Ni) was severely phytotoxic to all plant species tested. Toxicity symptoms in dicots included interveinal chlorosis and necrosis of leaves. In grasses, a banded chlorosis was present. Two limestone rates, 2.5 and 50 Mg ha⁻¹, were included in the test. Both liming and plant species significantly affected soil pH, and 0.01 M Sr(NO₃)₂-extractable soil Ni. Increase in pH exponentially decreased Sr(NO₃)₂-extractable soil Ni. Grass species were more resistant to Ni toxicity than dicots. Liming soil to pH of 5.9–6.3 enabled good growth of several grass species, but dicot species were still stunted or died. Making the soil calcareous (pH 7.7–7.8) ameliorated Ni toxicity of this highly contaminated soil for all species tested. Concentration of Ni in shoots associated with 25% yield reduction varied among species ranging from 9 to 122 mg kg⁻¹ dry shoots.

^#Use of names of products by the U.S. Department of Agriculture neither guarantees or warrants the standard of the product, nor implies approval of the product to the exclusion of others that may also be suitable.

Keywords:

• Smelter
• Contamination
• Metal
• Extractability
• Liming
• Wheat
• Oat
• Radish
• Bean

Acknowledgments

This study was partially supported by Viridian Resources, LLC, Houston, Texas, in cooperation with Inco Limited, Toronto, Canada. Dr. Kukier was a visiting scientist from the Institute for Soil Science and Plant Cultivation, Pulawy, Poland during this research. We gratefully acknowledge the assistance of Dr. C. E. Green, Dr. G. Siebielec, and Mr. E. P. Brewer, in conducting the experiments, and in maintaining the growth chamber and analytical equipment.

Notes

^#Use of names of products by the U.S. Department of Agriculture neither guarantees or warrants the standard of the product, nor implies approval of the product to the exclusion of others that may also be suitable.