Bamboo scraps and hardwood chips biochar derived from a cone-truncated open fire kiln for use as a nutrition medium for agricultural purposeBenya Kasantikul, Ruengsak Auttaranakon and Arun KongkeawE3S Web Conf., 187 (2020) 03003DOI: https://doi.org/10.1051/e3sconf/202018703003