Patrick Mutonkole Senga, Maria Prado, Damase Khasa and Tatjana Janesic Stevanovic
The use of timber in techniques of soil aggradation helps to preserve the environment by recycling sub products and residues from forestry. However, the nature of timber conditions the degradation process. The present study aimed at characterizing and comparing the chemical characteristics of wood branches, and stems of Trema orientalis and Leucaena leucocephala. By modified lignin Klason, high amounts of lignin were found in the branches than in the trunk of Trema, contradicting the results observed for Leucaena. Cellulose concentration, obtained from Kurschner and Hoffner was higher in the branches and lower in the trunk of Leucaena than in Trema. Moreover, ash contents were higher in the branches than in the trunk. C:N and lignin: N ratios, with N values significantly higher in the branches, were higher in wood trunk than in branches. Moreover, all Trema ratios were higher than those found in Leucaena. However, branches lignin/N ratio, naturally weaker, would predict a more rapid decomposition of their lignocellulose material once on the ground. Overall, pyrolysis GC-MS of branches and stems identified compounds derived mainly from lignin, followed by polysaccharides.