Harnessing native plants for sustainable heavy metal phytoremediation in crushing industry soils of Muzaffarabad

Abstract

Phytoremediation provides an environmentally sustainable and cost-effective technique to mitigating heavy metal contamination in industrial and mining regions. This study explored the phytoremediation capabilities of three indigenous plant species Rumex hastatus , Amaranthus spinosus , and Cirsium arvense in soils contaminated with heavy metals from industrial and mining sites in Muzaffarabad, Azad Kashmir. Physico-chemical analysis of soil revealed alkaline pH (8.16), high electrical conductivity (dS m ─1 ) and the presence of metals, with Fe (169.44 mg/kg) and Zn (86.28 mg/kg) being predominant. Heavy metal accumulation in plant tissues followed the pattern Fe > Zn > Cu > Mn > Ni > Hg > Cd > Cr > As > Pb, with higher metal concentrations in roots except for Fe and Pb in R. hastatus . Photosynthetic pigment analysis showed the highest chlorophyll content in R. hastatus , while carotenoids were highest in A. spinosus . Antioxidant enzyme activities indicating oxidative stress mitigation, with R. hastatus showing the highest overall activity. Gas exchange parameters revealed the highest photosynthesis and transpiration rates in R. hastatus , while stomatal conductance and internal CO 2 concentration were highest in C. arvense . Proline and total soluble were maximum in R. hastatus . Bioconcentration factor (BCF) values were greater than 1 for most metals, with R. hastatus showing hyperaccumulation potential for Fe and Pb. The findings suggest that R . hastatus is a strong hyperaccumulator for Fe and Pb, while all species show promising phytostabilization, especially for Hg. Future research using these species could enhance soil decontamination strategies and promote sustainable environmental management. • Three plant species near an industrial site were studied for pollution control. • Rumex hastatus excelled in Fe, Pb phytoextraction and heavy metal stabilization. • Photosynthesis, gas exchange, and antioxidants improved under metal stress. • Proline and soluble sugars enhanced stress tolerance and remediation.