Heavy metal distribution and soil–plant transfer dynamics using Helichrysum arenarium in Bitlis (Eastern Türkiye)

This study investigates the distribution of selected heavy metals in soils and evaluates soil–plant transfer dynamics using Helichrysum arenarium in the semi-arid volcanic environment of Bitlis (Eastern Türkiye). Soil and corresponding plant samples were collected from 19 sampling sites representing roadside, agricultural, and semi-natural areas. Metal concentrations (Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, and Pb) were determined using ICP-MS following acid digestion procedures. Bioaccumulation factors (BAF) were predominantly below unity for most metals (mean range 0.08–0.70), although site-specific values exceeded 1 at certain locations. Pearson correlation analysis revealed weak to moderate relationships between soil and plant concentrations (r < 0.35 for most metals), suggesting non-linear or regulated uptake behaviour. Although localized elevations of Pb and Ni were observed in certain sites, the absence of consistent high BAF values indicates limited systematic transfer to plant tissues.Although localized elevations of Pb and Ni were observed in certain sites, low BAF values indicate restricted transfer to plant tissues. The findings demonstrate that Helichrysum arenarium exhibits metal tolerance and partial exclusion behaviour rather than strong predictive bioaccumulation-based assessment. This study provides baseline data for heavy metal distribution in the Bitlis region and contributes to understanding soil–plant interaction dynamics in semi-arid volcanic ecosystems.