No abstract

No abstract

Metal(loid) soil contamination is a widespread issue and its remediation a priority.Phytoremediation involves the use of plants to stabilize/extract metal(loid)s and prevent spreading of contaminants. Salicaceae are fast growing trees that can tolerate and accumulate metal(loid)s. Amendments may be needed to facilitate plant growth on the contaminated substrate. Biochar, the solid product of pyrolysis, can ameliorate soil properties and reduce metal(loid) bioavailability but showed low affinity toward arsenic. Redmud, a waste product, can immobilize arsenic and other metal(loid)s and improve soil conditions. To evaluate the potential of those amendments to immobilize metal(loid)s and facilitate the establishment of a cover vegetation with willow (Salix dasyclados Wimm.), a pot experiment was conducted using several carbonbased materials (biochar and activated carbon) and redmuds. Two carbon-based materials and two redmuds were selected for the pot experiment based on characteristics and sorption tests. A former mining soil was amended with these products and Salix dasyclados cuttings were planted. Biochar and one redmud improved growth of Salix dasyclados Wimm. Redmud, which is cheaper than biochar, performed equally well as the biochar at a lower application rate. It can therefore be concluded that the application of redmud, associated to Salix dasyclados, could be an option for the phytoremediation of an As and Pb contaminated soil. However, these results need to be evaluated on a bigger scale to assess the gain brought by the combination of redmud and Salix dasyclados on the contaminated area.

Highlights Severity of surface transformation after aging was high in low temperature wheat straw biochar compared to biochar produced at higher temperatures  Aged wheat straw biochars performed better than the fresh biochars at 500 °C and 600 °C production temperatures while fresh wheat straw biochar performed better than the aged form only at 400 °C  Alkalinity and surface functionality in wheat straw biochar played an important role in immobilization of

Highlights Sawmill byproduct was used to produce biochar  Addition of biochar increased the pH, EC and nutrient content in the medium  The inclusion of biochar in 25% to 50% volume ratio improved plant growth parameters compared to peat-only media  Higher biochar proportions in the medium diminish the physico-chemical properties and plant growth parameters