PHYTOEXTRACTION OF SELECTED METALS BY THE FIRST AND SECOND GROWTH SEASONS OF Spartina Alterniflora

Abstract

Continued studies on the use of the plant Spartina alterniflora for the removal of selected metals (copper, chromium, iron, lead, and zinc) in soils are presented. Results showed that at a second harvest, at approximately 11 months after a first harvest, there was a definite trend with increased time in the accumulation of the metals both in the roots, e.g., in the control from 3.30 (first harvest) to 9.8 ppm (second harvest), for lead, spiked from 21 (first harvest) to 87 ppm (second harvest) for chromium, and 6969 (first harvest) for 8228 ppm (second harvest) for iron in the real soil of Bayou d'Inde in southwest Louisiana and in the above portion of the plant, e.g., in the control from 2.67 (first harvest) to 5.5 ppm (second harvest), for lead, spiked from 5 (first harvest) to 35 ppm (second harvest) for chromium, 13 (first harvest) for 23 ppm (second harvest) for copper in the real soil of Bayou d'Inde. It was also noted that the amount or concentration of metal in soil (control, spiked, and real soil from Bayou d'Inde in southwest Louisiana), decreased with time from initial studies and a first harvest, and was attributed to a more even or homogeneous distribution of metals in the soil with time. Phytoextraction rates of the five metals ranged from 10.1 (chromium) to 908.7 (iron) mg/m² yr in the above ground plant.

Keywords:

• metals
• phytoextraction
• Spartina alterniflora
• soils

Notes

First harvest results were taken from Ref. [6].

Metal content = metal concentration (µg/g) * biomass (g).