Effect of fibre and vessel biometry on wood combustibility of native Miombo tree species

Fibres and vessels represent the largest proportion of anatomical elements in hardwood tree species. They exert significant effects on various properties of the wood, which, consequently, have several implications for the use of the wood. However, the effect of these elements on wood combustion behaviour is still poorly analysed in the literature. The present study aimed to evaluate the effect of fibre and vessel biometry on wood combustibility. The length, width and cell wall thickness of fibre, diameter of the lumen, and length and width of vessels were measured from five native Miombo tree species in Mozambique, namely Brachystegia boehmii Taub., Brachystegia spiciformis Benth., Julbernardia globiflora (Benth.) Troupin, Parinari curatellifolia Planch. ex Benth. and Uapaca kirkiana Müll. Arg. The fibre quality index and cell wall thickness were determined based on fibre biometry. The flexibility coefficient and the wall fraction are inversely proportional indices and individually affected most of the combustion parameters. Wood ignition is driven by large lumen diameter and flexibility in fibres. In addition, cell wall thickness and a larger wall fraction increase wood combustion.