The golden wattle, Australia’s floral emblem, is an ideal candidate for rehabilitating mine sites, according to new research from the University of South Australia.
Most planted trees and herbs remove heavy metals from the soil. But these heavy metals accumulate in the plant, spreading to the worms, birds, and other wildlife that feed off the plants.
However, wattle is different.
“Wattle trees take up very little copper. That means the majority of the on-site copper remains in the soil,” according to Ramkrishna Nirola, who worked at an abandoned copper mine to examine the suitability of 26 tree species for environmental remediation.
A small amount of copper is absorbed but it becomes bound up within the leaf structure, so it is unavailable for uptake by worms and other invertebrates.
The potential environmental impacts are significant.