This paper analyses the effects of substrate
properties and environmental conditions on spontaneous
vegetation of soil and sludges from a dismantled steel plant
moderately polluted by heavy metals and polycyclic aromatic
hydrocarbons. Plant colonization was monitored in
the presence or absence of acidic peat for 5 years both
inside the degraded brownfield site and after transferral
into a nearby Oak Park environment. Overall, 57 plant
species grew healthily on the substrates, with peat
enhancing plant growth in the unfavourable brownfield
site. Most of the species were found in the park (91 %),
showing plant colonization was mainly affected by the
immediate environment rather than by substrate properties.
Restricted metal uptake and tissue accumulation by selected
plants were measured, with only
Daucus carota
showing a higher ability to translocate metals to shoots
(shoot/root metal concentration quotient >1 with peat).
Phytostabilization with native plants represents an economically
more realistic and cost-effective option than
excavation, soil washing and sludge disposal, especially for
vast industrial sites. Addition of organic matter and
planting strategically selected vegetation islands could
facilitate the spontaneous recovery of such highly degraded
environments.
