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Woody plant resprouting has received considerable attention in the last two decades as human disturbances continue to encroach on terrestrial ecosystems globally. We examined the regeneration mechanisms of a Caatinga dry forest in the context of slash-and-burn agriculture and resprouting ability of the local flora. We excavated two old fields (from 32) experiencing early forest regeneration dominated by the tree Pityrocarpa moniliformis (Fabaceae) to map clonal propagation and, in parallel, submitted 260 seedlings from 13 woody plant species to experimental clipping. What seemed to be ‘seedlings’ popping up around P. moniliformis stumps and remaining adults actually were condensed sets of root suckers connected via complex networks of long, ramified shallow horizontal roots without taproots. We mapped respectively 39 and 783 connected root suckers, which summed 96 m and 910 m in root length. Regarding the seedlings, 33% resprouted across nine species with resprouting rates varying between 5–100%. Seedling height before clipping positively influenced resprouting vigour. Our preliminary results suggest that the Caatinga dry forest supports a relatively high proportion of resprouting species, some of them able to clonally propagate and playing an ecosystem-level role by responding to early forest regeneration and high abundance/biomass across both regenerating and old-growth forests.

Biometric data of fruits, such as volume and density, can be applied for different ecological and economic purposes. Non-destructive allometric models based on morphometric dimensions can be more accurate and practical in field conditions than destructive methods used in traditional growth curves. Babassu is a Brazilian native palm tree with wide distribution whose fruits are of high importance for socioeconomic and cultural purposes, in addition to having high potential for biodiesel production. The objectives of this work were to analyse morphometric and biometrically the babassu fruits and create a non-destructive allometric model to estimate their volumes and densities from their dimensions. Weight, polar and longitudinal diameters, volume and density were measured in 156 fruits. The dimensions were applied in the formula to estimate the volume of an ellipsoid object, which matches the shape of the babassu fruit. The non-destructive allometric model was created by calculating a correction factor to adjust the precision of the formula. Our model improved the accuracy of volumes and densities calculated by 24%. Strong correlations were also found between the morphometric and biometric parameters. Therefore, this allometric model can be used to assist in selecting the most suitable fruits to improve economic, propagation and conservation studies.

Seedling recruitment, community assembly, and forest regeneration, while receiving substantial attention in tropical rain forests, have received little attention in tropical dry forests. Here, we examine the structure, composition, and diversity of woody seedling assemblages across 19 forest stands in a human‐modified landscape of Caatinga dry forest, assessing the role played by rainfall, aboveground biomass, and chronic anthropogenic disturbances (i.e., livestock grazing pressure and wood extraction) as assembly forces. We quantified a large set of community‐level attributes including functional traits related to water availability, physical protection, and survival success. We recorded a total of 544 seedlings from 59 species, giving a mean density of 28.6 ± 15.8 (mean ± SD) seedlings and 7.42 ± 4.35 species per 1000 m2. The 10 most abundant species accounted for almost 80% of all individuals, whereas nearly half of the species were considered rare (i.e., less than two individuals across the 19 forest stands). Seedling assemblages differed structurally and taxonomically from adult assemblages, exhibiting lower abundance, species richness, and divergent dominant species. Moreover, the dominant species of seedlings exhibited low adult‐to‐offspring ratios. Seedling species and assemblages were functionally diverse, with community‐level attributes mostly affected by rainfall. Our results suggest that the Caatinga dry forest in sandy soils support seedling assemblages, to some extent, structured along environmental gradients, with rainfall and wood extraction acting as key community assembly forces. Although seedling assemblages are functionally diverse, they are relatively low density and taxonomically impoverished at local and landscape scales, potentially impacting successional trajectory and long‐term forest dynamics. Abstract in Portuguese is available with online material.

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