The goal of this study was to evaluate the soil
properties and their modifications within the rhizosphere of
spontaneous vegetation as key factors to assess the phytomanagement
of a salt marsh polluted by mining wastes.
A field survey was performed based on a plot sampling
design. The results provided by the analyses of rhizospheric
soil (pH, electrical conductivity (EC), organic
carbon, total nitrogen, etc.) and metal(loid)s’ phytoavailability
(assessed by EDTA) were discussed and related to
plant metal uptake. The averages of pH and EC values of
the bulk soil and rhizospheric samples were in the range of
neutral to slightly alkaline (pH 7–8) to saline (> 2 dS m-1
respectively. Heavy metal and As concentrations (e.g.
~600 mg kg-1
As, ~50 mg kg-1
Cd, ~11,000 mg kg-1
Pb) were higher in the rhizosphere for both total and
EDTA-extractable fraction. Phragmites australis
the highest concentrations in roots (e.g. ~66 mg kg-1
~1,770 mg kg-1
Zn) but not in shoots, for which most of
plant species showed low values for Zn (<300 mg kg-1
but not for Cd (> 0.5 mg kg-1
) or Pb (~20–40 mg kg-1
Vegetation distribution in the studied salt marsh looked to
be more affected by salinity than by metal pollution. The
free availability of water for plants and the incoming
nutrient-enriched effluents which flow through the salt
marsh may have hindered the metal(loid)s’ phytotoxicity.
The phytomanagement of these polluted areas employing
the spontaneous vegetation is a good option in order to
improve the ecological indicators and to prevent the
transport of pollutants to nearby areas.