Phytostabilisation in Mine Waste Dumps: The Role of Selected Tree Species in the Lignite Mines of Western Macedonia, Greece

Abstract

This study investigates the potential of selected plant species for environmental restoration and phytostabilisation in lignite mine waste dumps in Western Macedonia, Greece. Field sampling was conducted in three representative sites, where both soil and plant tissues were collected and analysed using X-ray Fluorescence (XRF). A total of six species (Pinus spp., Acacia spp., Populus spp., Cupressus spp., Cuprocyparis leylandii, and Tamarix spp.) were evaluated for their ability to grow in low-fertility substrates and their capacity to accumulate potentially toxic elements (PTEs). The findings indicate that soil chemistry is primarily influenced by geogenic factors, with elevated concentrations of Ca, Si, Mg, and K, consistent with the carbonate-rich geology of the Ptolemaida basin. Concentrations of PTE (Ni, Cr, Zn, Pb) remain below established toxicity thresholds, and Hg levels are negligible (<0.03 mg/kg). Plant tissue analysis revealed selective nutrient uptake and limited translocation of PTEs to aerial parts. Although the studied species do not exhibit hyperaccumulator characteristics necessary for phytomining, they exhibit strong phytostabilisation capacity, supporting erosion control and ecological restoration without increasing environmental risk.