Phytoremediation Potential of Pityrogramma Calomelanos Var. Austroamericana and Pteris Vittata L. Grown at a Highly Variable Arsenic Contaminated Site

Abstract

This study examined the phytoextraction potential of two arsenic (As) hyperaccumulators, Pteris vittata L. and Pityrogramma calomelanos var. austroamericana at a historical As-contaminated cattle dip site in northern New South Wales (NSW), Australia. Total As concentration in the surface soil (0–20 cm) showed a better spatial structure than phosphate-extractable As in the surface and sub-surface soil at this site. P. calomelanos var. austroamericana produced greater frond dry biomass (mean = 130 g plant⁻¹) than P. vittata (mean = 81 g plant⁻¹) after 10 months of growth. Arsenic concentration and uptake in fronds were also significantly higher in P. calomelanos var. austroamericana (means = 887 mg kg⁻¹ and 124 mg plant⁻¹) than in P. vittata (means = 674 mg kg⁻¹and 57 mg plant⁻¹). Our results showed that under the field conditions and highly variable soil As at the site, P. calomelanos var. austroamericana performed better than P. vittata. We predict that P. calomelanos var. austroamericana would take approximately 100 years to reduce the total As to below 20 mg kg⁻¹ at the site compared to ≥ 200 years estimated for P. vittata. However, long-term data are required to confirm these observations under field conditions.

KEY WORDS:

• arsenic
• geostatistical methods
• phytoextraction
• Pityrogramma calomelanos var. austroamericana
• Pteris vittata

ACKNOWLEDGMENTS

Nabeel gratefully acknowledges the Higher Education Commission of Pakistan for the award of PhD scholarship. The project has been assisted by the NSW Government through its Environmental Trust. The authors are thankful to Dr. Thomas Bishop for his assistance in statistical analyses. We would also like to thank George Nastase, Victor Warren, Desmond, Larry Falls, Stephen Kimber, Scott Petty, and Joshua Rust at the Wollongbar Primary Industries Institute.