{Reference Type}: Journal Article {Title}: Co-pyrolysis of chicken manure with tree bark for reduced biochar toxicity and enhanced plant growth in Arabidopsis thaliana. {Author}: Lataf A;Pecqueur I;Huybrechts M;Carleer R;Rineau F;Yperman J;Cuypers A;Vandamme D; {Journal}: Sci Rep {Volume}: 14 {Issue}: 1 {Year}: 2024 06 17 {Factor}: 4.996 {DOI}: 10.1038/s41598-024-62468-3 {Abstract}: Co-pyrolysis of chicken manure with tree bark was investigated to mitigate salinity and potentially toxic element (PTE) concentrations of chicken manure-derived biochar. The effect of tree bark addition (0, 25, 50, 75 and 100 wt%) on the biochar composition, surface functional groups, PTEs and polycyclic aromatic hydrocarbons (PAH) concentration in the biochar was evaluated. Biochar-induced toxicity was assessed using an in-house plant growth assay with Arabidopsis thaliana. This study shows that PTE concentrations can be controlled through co-pyrolysis. More than 50 wt% of tree bark must be added to chicken manure to reduce the concentrations below the European Biochar Certificate-AGRO (EBC-AGRO) threshold. However, the amount of PAH does not show a trend with tree bark addition. Furthermore, co-pyrolysis biochar promotes plant growth at different application concentrations, whereas pure application of 100 wt% tree bark or chicken manure biochar results in decreased growth compared to the reference. In addition, increased plant stress was observed for 100 wt% chicken manure biochar. These data indicate that co-pyrolysis of chicken manure and tree bark produces EBC-AGRO-compliant biochar with the potential to stimulate plant growth. Further studies need to assess the effect of these biochars in long-term growth experiments.