Biochar hydrological characteristics in related to branch wood properties

Abstract

Branch wood possesses unique properties that may affect biochar characteristics. Despite the abundance of broad studies on biochar, the correlation between feedstock properties and biochar hydrological characteristics has yet to be elucidated. Therefore, in this work the tree branch wood properties of three feedstocks (Acacia gerrardii Benth., Tamarix aphylla (L.) H. Karst., and Eucalyptus camaldulensis Dehn.) were investigated and compared with the characteristics of biochar produced by pyrolysis at 300 °C, 400 °C, and 500 °C. It was found that a higher lumen fraction resulted in a more porous structure, thus increasing the ability of biochar to absorb and retain water. Acacia gerrardii absorbed 403% and retained 73.6% water, whereas T. aphylla and E. camaldulensis held 396% and 342%, and then retained 71.5% and 68.1% water, respectively. The water holding capacity and water retention ability were lower in biochars pyrolyzed at 300 °C than 500 °C. The present findings demonstrate that fiber lumen diameter and parenchyma properties provide indicators of biochar hydrological characteristics generated from tree branch wood.