Determination of phytoextraction potential of plant species for toxic elements in soils of abandoned sulphide-mining areas

Cistus salviifolius a promising species for mine wastes remediation

“…Like arsenic and lead, translocation coefficients of antimony were small (b0.48) for all the studied C. salviifolius populations. Similar values for antimony translocation coefficients were also reported for other species from São Domingos mine (Freitas et al, 2009) ( Fig. 2).…”

“…Trace elements concentrations in São Domingos soils are in the same range of other results reported for São Domingos mine (Freitas et al, 2009;Santos et al, 2009;Tavares et al, 2008). In São Domingos soils total concentrations of arsenic, antimony and lead seem to be related (r N 0.92).…”

“…This behaviour was also observed in other species from mining areas (Freitas et al, 2009), suggesting a tolerance mechanism which inhibits translocation above a certain uptake level. Similar translocation ratios were also …”

“…The similar copper concentrations in the aerial parts of this species can suggest a tolerance and homeostatic mechanisms that maintain the correct copper concentration in leaves (not reaching the toxic (20-100 mg/kg) or the deficient concentrations (2-5 mg/kg) - Adriano, 2001;Kabata-Pendias and Pendias, 2001 As zinc is an important micronutrient, like copper and manganese, for various metabolic functions, plants from all the areas transport mainly zinc from roots to the aerial parts (TranslC SD = 2.14; TranslC C = 2.72; and TranslC G = 3.19). This behavior is not standardized for all plants species growing in São Domingos (Freitas et al, 2009). The obtained results for zinc in the C. salviifolius aerial parts from São Domingos are in the same range of concentrations in leaves (226.2 mg/kg) and twigs (130.4 mg/kg) for the same species, reported by Freitas et al (2004a) for São Domingos mine areas where soils contain smallest zinc concentration (158.9 mg/kg).…”

“…This tolerance is due to the development of one or various biological, chemical or physiological adaptations. Reduction of trace elements uptake, accumulation in roots and the consequent reduction of the translocation to shoots, re-mobilization of trace elements to mature or senescent leaves, and activity of antioxidative enzymes are some tolerance mechanisms observed in plants growing in mining areas (Freitas et al, 2009;Murciego et al, 2007;Oliva et al, 2009;Santos et al, 2009). The natural succession of plants in mining areas can constitute distinctive metal/metalloid-tolerant communities (ecotypes) which have usually low diversity.…”