Investigating the Absorption Behavior of Plants Selected from Darreh-Zereshk Copper Mine for Phytoremediation purposes

The purpose of this research was to study various plant species  and to model the absorption behavior  thereof in relation to the various elements in and around of Darreh Zereshk Copper Mine to find the most suitable indigenous species for phytoremediation study. The goal is reducing the impacts and environmental pollution of the pollutant elements. For this purpose, 36 plant samples (including 17 different species) and 32 soil samples (in two different size fractions) were taken. After preparation and application of different digestion methods, the samples were analyzed by atomic absorption method for copper, iron and lead elements. By using four different solvent extraction methods, the absorption behavior of the plants was modeled and the best method was identified as extracted by organic solvent EDTA. This solvent could better detect the absorption behavior of the plants and distinguish contaminated areas from virgin and non-contaminated areas. The soil with smaller size fraction is more enriched of the metals and the copper presented in this fraction is absorbed by the solvent at higher concentrations. This suggests that the fine particles of the soil scavenged a higher content of metal by absorption property. By calculating the bioconcentration factor, the absorption behavior of different plant species was compared in contaminated and non-contaminated areas, and accordingly, the species of “Hertia Angustifolia” , “Glycyrrhiza Globra” and “Euphorbia” were identified as accumulator species and “Tamarix”, “Alhagi”, “Astragalus” and”Artemisia Sieberi Besser” determined as hyper-excluder species. “Hertia Angustifolia” species has a fairly good abundance in the region, therefore it can be introduced and used as an indigenous indicator species for the purpose of phytoremediation.