The bioaccumulative potential of heavy metals in five forest species
living in mining environments in the Ecuadorian Amazon region
Abstract
Pollution caused by heavy metals in soils and ecosystems is an
environmental problematic that requires urgent attention due to the
ecological problems that it generates. Forest species can be used to
mitigate contamination because of their potential to bioaccumulate
contaminating metals. Hence, the aim of this research was to identify
tree species with good heavy metal bioaccumulating capacities that can
contribute to mitigate pollution. The bioconcentration factor for five
forest species, such as: Spanish cedar ( Cedrela odorata L.),
cutanga ( Parkia multijuga Benth.), guaba or ice cream bean (
Inga edulis Mart.), guarumo ( Cecropia ficifolia Warb. ex
Snethl.) and Amazon tree grape ( Pourouma cecropiifolia Mart.),
commonly found in the Ecuadorian Amazon was analysed, based on the
relationship between the leaves and soil concentration of the heavy
metals. For heavy metal analysis in leaves and soil samples of each
plant species, atomic absorption spectrometry was used. The results
showed that P. cecropiifolia had the highest bioconcentration
factor for lead, C. odorata for cadmium and nickel, and I.
edulis had the highest potential for iron and aluminium absorption. Any
kind of correlation between the concentration of each element in soil
and leaves was found, which shows that the bioaccumulation capacity of
the species studied does not determine the concentration of metals in
the soil.