Extraction method influences dissolved organic matter from invasive Japanese knotweed-derived biochar and environmental implications

Valorization of invasive plant biomass through pyrolysis into biochar offers opportunities for waste management and resource recovery. However, the release of biochar-derived dissolved organic matter (BDOM), which influences carbon dynamics and pollutant mobility, remains poorly understood. This study investigated BDOM from Japanese knotweed biochar (500 °C) using seven extraction methods, covering mild aqueous conditions (water and CaCl2), salt effects (NaCl), standardized acidic leaching tests