The work focuses on the screening of
Polyalthia longifolia
and
Aloe vera
for
their phytoextractability of heavy metal in soil of the Niger Delta. 5kg of soil was polluted
with 100 mg of Zn, Fe and Pb each replicated 9 times. Each set was separated into 3
subgroups. The subgroups were phytoextracted with
Polyalthia longifolia and
Aloe vera
alongside a control (no phytoextraction) respectively. After 12 weeks, the concentration of
Lead, Iron and Zinc in soils, roots and shoots was determined. Results showed that the two
plants have phytoextraction ability with reductions in Zn, Fe, and Pb in the phytoextraction
soil . Metal transfer factor was PB:
Aloe vera (0.881) >
P. longifolia (0.315); Zn:
P. longifolia
(0.614) >
Aloe vera (0.606); Fe:
Aloe vera (0.812) >
P. longifolia (0.774). Translocation
factors for the two plants were in the order:
Zn: P. longifolia (0.79) >
Aloe vera (0.36);
Fe:
P. longifolia (0.63) >
Aloe vera (0.05);
Pb: P. longifolia (0.57) >
Aloe vera (0.23). Since the
translocation factors were < 1, the plants can be classified as non- hyperaccumulators for
these metals.
