Background The carob tree (Ceratonia siliqua L.) is one of the most iconic tree species of the Mediterranean region, with valuable economic, ecological and cultural value. Carob has been exploited around the Mediterranean region since antiquity and has been regarded as an important component of natural habitats and traditional agroecosystems. Several studies have focused on its morphological, biochemical, and genetic diversity. However, less is known about the intraspecific variation of seed traits. In this regard, and as an overall objective, we intend to evaluate the amplitude and the expression of intraspecific variations of carob seed traits at different ecological scales ranging from individual trees to different geographical landscapes. In addition, we investigated how the climate along the study area affects the extent of carob seed variability. Using image analysis techniques, we measured seven traits related to the size and the shape of 1740 seeds collected from 18 populations of spontaneous C. siliqua distributed along a latitudinal transect in Morocco under different bioclimatic conditions. Results The morphometric analysis of carob seed showed the effectiveness of adopted approach to highlight the amount and the amplitude of intraspecific variation according to geographic and climatic factors. Seed trait analysis revealed high intraspecific variability, explained by differences between and among carob populations and geographic zones. Seed area, perimeter, length, and width showed the largest variability between geographic zones. However, circularity, aspect ratio, and seed roundness showed higher variability at the tree level. Finally, our results show that seed traits vary depending on altitude and climate condition. Conclusions Revealing the amount and the structure of intraspecific traits variability of carob seed provides interesting insights to understand the mechanisms underlying trees adaptation to various environmental and ecological conditions. Therefore, intraspecific variation of seed traits should be integrated into trait-based functional ecology to assess plant species responses to environmental changes.

Miombo is one of the most widely distributed ecosystems in Angola, with a great social and environmental value. Thus, the rural population uses the biomass as fuel and miombo provides important ecosystem services, such as its carbon sequestration capacity. The objectives of this work were (i) to assess deforestation in miombo forest in Huambo province (Angola) during the last 20 years, (ii) to evaluate carbon storage capacity of miombo, and (iii) to calculate the charcoal productive capacity of those forests. From 2000 to 2019, 359,130 ha (12.96%) were deforested in Huambo province. Thirty-six woody species were identified as major components of miombo forest, the most frequent being Albizia anthunesiana, Brachystegia spiciformis, Julbernardia paniculata, Monote spp., Brachystegia boemii, Isoberlinea angolensis, Anisophyllea boehmii, Syzygium guineense, and Erythrophleum africanum. The total biomass estimated in miombo forest was 195.05 Mg ha−1 (55.02 Mg ha−1 radical and 140.04 Mg ha−1 area), with a total wood volume of 78.57 m3 ha−1. This represents values of 91.67 Mg ha−1 of accumulated carbon and 336.13 Mg ha−1 of CO2 equivalent. The potential charcoal productivity was 15,359.9 kg ha−1, corresponding to 24.78 trees ha−1. The Annual Allowable Cutting Volume was 10.77 m3 ha−1 year−1, 14.13 m3 ha−1 year−1, 21.17 m3 ha−1, and 32.85 m3 ha−1 year−1 for rotation lengths of 55, 40, 25, and 15 years, respectively, corresponding to a potential annual charcoal productivity of 2107.08 Kg ha−1 year−1, 2762.96 Kg ha−1 year−1, 4139.21 Kg ha−1, and 422.56 Kg ha−1 year−1. However, deforestation rates in the last 19 years and low charcoal productive capacity could compromise the sustainability of the Miombo ecosystem and its value as an ecosystem service provider in the province if appropriate management strategies are not developed.