ABSTRACT Background: The fibres dimensions vary along a tree trunk, and these variations are related to the apical meristem and vascular cambium activities; understanding these variations would guide the best use of wood. There have been studies on the pattern of fibres dimensions variation along the tree trunk in the radial and longitudinal directions; however, the vast majority do not take into account the structure of the annual growth rings. Hence, this study aimed to obtain the pattern of fibres dimensions variation and their quality indexes along the tree trunk take into account the structure of the annual growth rings. Two Eucalyptus urophylla x Eucalyptus grandis hybrid clones were used in the study. Ten-year-old trees were selected and discs were removed from 13 longitudinal positions. The disks were prepared and the growth rings were subsequently identified and the samples used for maceration were collected. Twenty fibres were measured in the annual growth rings present in each longitudinal position. Results: In the longitudinal direction, within the annual growth rings, the fibre dimensions and their quality indices did not show a well-defined pattern of variation. In the radial direction, the length, cell wall thickness, wall fraction, and Runkel ratio of the fibres tended to increase following the pith-bark direction, while the lumen diameter and flexibility coefficient decreased. Conclusion: Nevertheless, the fibre width and fibre slenderness index did not present a well-defined pattern of variation in the radial direction.

To overcome the negative impacts of unsustainable exploitation of forest resources, the Mozambican government has been trying to regulate the supply and demand of biomass, the main source of energy for the majo rity of the population. This paper reviews policies implemented in Mozambique aimed at increasing domestic energy production while promoting a sustainable use of biomass. Despite the efforts to reduce the level of biomass energy use, it remains the most attractive to local populations and, therefore, still has great importance in the national energy mix. Thus, rather than looking at woodfuels as an environmental problem, regulations should also recognise the dependence of local communities on these resources. Firewood remains the main energy source in rural areas, and approximately 0.36% of the forest in Mozambique is lost every year. The replacement of firewood and charcoal by other renewable sources of energy is still far from reality. Charcoal production continues to be carried out in traditional low-yield ovens and the levels of forest degradation are still alarming. As such, improvements to the existing regulation framework are still needed. HIGHLIGHTS: • Woody biomass remains the most attractive energy source in Mozambique. • The government implemented policies to address unsustainable use of biomass. • The policies did not lead to a sustainable use of biomass. • Policy design should consider both technical and socio-cultural aspects.