Heavy metal concentrations (Cu, Pb and Zn) in three rangeland species and adjacent soils around Kiasar Cement Factory in Northern Iran

Soil pollution by heavy metals has become an environmental problem due to their long-term sustainability and ecologically harmful effects. In soils contaminated by heavy metals, establishing plants with the ability to grow in affected areas, adapt and uptake heavy metals is both scientifically and economically beneficial. In the current study, soil and plant samples were taken using a systematic random sampling approach within a 500, 1250 and 2000 meter radius of the centre of Kiasar cement factory in Mazandaran Province. For each distance, three plant species (such as Astragalus, Artemisia and Convolvulus) and their adjacent soils were sampled in three replications resulting 54 samples (27 plant and 27 soil samples). The concentrations of Pb, Cu, and Zn in the samples were determined using an ICP-OES Device and data analyzed statistically using a randomized complete block design. Analysis of variance results in this study showed that the amount of heavy metals in the soil was higher than those obtained in plant species tissues (p ≤ 0. 05). The mean comparison of data showed that distance from factory had a significant affect on copper and lead concentrations in both soil and plant tissues (p≤ 0. 05). While the copper concentration increased in both the soils and plant tissues, the amount of lead decreased with the increasing distance. The distance had no significant effect on zinc concentration in soil samples, but there were significant differences in plant species tissues and they do not follow the regular process. The correlation of heavy elements between plant species and soils showed that Astragalus and Artemisia had a significant correlation with copper (r = 0. 7) and lead (r = 0. 5), but convolvulus only had a significantly positive correlation with Zn. Due to the high potential of Astragalus and Artemisia species in up-taking the heavy metals, these species can be used in refining contaminated areas with same ecological conditions.