From Transformation\nto Life Cycle Assessment of Biochar:\nA Case Study of Wheat Straw Biochar

Biochar,\nas a carbon-rich material, exhibits significant potential\nfor industrial applications. While numerous research endeavors have\nfocused on its interactions within soil ecosystems, scant attention\nhas been given to its behavior and potential impact on aquatic environments.\nIn this study, we conducted an investigation to compare the environmental\nimplications of pristine biochar with those of aged biochar. Initially,\nwe assessed the interaction between biochar and key water quality\nindicators, revealing the release of endogenous ions (e.g., NH<sub>4</sub><sup>+</sup>, NO<sub>3</sub><sup>–</sup>, PO<sub>4</sub><sup>3–</sup>, Cu<sup>2+</sup>, and Cd<sup>2+</sup>) as well\nas organic substances (e.g., DOC) from both pristine and aged biochar\nsamples. Aged biochar released higher amounts of ions and organic\nsubstances than pristine biochar due to the change in the structure\nand properties of aged biochar. Environmental risk and toxicity of\npristine and aged biochar were subsequently evaluated using the potential\necological risk index (RI) and the impact on growth of <i>Chlorella\nvulgaris</i>, respectively. The values of RI for Cu indicated\na very low degree of environmental risk, while those for Cd were dependent\non water quality for surface water. Our study provided thorough analysis\non the environmental assessment of biochar by combining experimental\nenvironmental transformation and life cycle assessment (LCA) analysis,\nsuggesting biochar could have excellent environmental applications.