Tropical forests differ widely in floristic composition, stand structure, standing volume, and carbon storage, yet comparative evidence across contrasting tropical forest types remains limited. This study examined whether variation in standing volume and carbon stocks among contrasting tropical forests was more closely associated with structural attributes or with diversity-related patterns. Two tropical wet forests in Colombia and one tropical semi-deciduous forest in Mexico were evaluated using 40 circular plots of 500 m² established within a 100 ha reference area in each forest, where all trees with DBH > 10 cm were measured. Floristic composition, ecological dominance, diversity, dendrometric attributes, standing volume, biomass, and carbon stocks were estimated using a common analytical framework. The two wet forests showed higher effective diversity, broader taxonomic dominance, greater basal area, mean height, standing volume, biomass, and carbon stocks than the tropical semi-deciduous forest. In contrast, the semi-deciduous forest showed stronger dominance concentrated in fewer taxa, especially Euphorbiaceae, a pattern that may reflect the ecological suitability of this family under more seasonal and water-limited conditions. At the family level, standing volume, biomass, and carbon were distributed more evenly among dominant families in the wet forests, whereas they were more concentrated in fewer lineages in the semi-deciduous forest. Basal area showed the strongest association with standing volume, total biomass, and total carbon, followed by mean height and mean DBH. Overall, the results indicate that, under the conditions evaluated, structural organization was more closely associated with standing volume and carbon storage than diversity alone, while diversity acted as a complementary correlate.

Forest restoration depends on producing seedlings able to convert nursery inputs into functional traits that persist after outplanting. This study evaluated whether contrasting nursery resource-management profiles, derived from container volume, fertilization, and irrigation, shaped seedling quality and field establishment of Pinus devoniana. Seedlings were conditioned for six months under eight profiles and validated during one year under field conditions. Nursery evaluation included morphology, biomass allocation, Dickson Quality Index (DQI), nutrient status, and proline; field validation included survival, growth, ectomycorrhization, stomatal density, and lignification. Profiles differed significantly in root collar diameter, height, root biomass, total biomass, root–shoot ratio, and DQI. The 5 L fertilized and irrigated profile produced the highest integrated quality, with 140.9% more root biomass than the weakest root profile and 144.3% higher DQI than the lowest-quality profile. Nitrogen- and proline-separated nutrient and stress responses showed that higher nutrient status did not always imply lower stress. Field survival reached its highest value under the 5 L fertilized and irrigated profile, exceeding several 1 L profiles by 74.8%. DQI was positively associated with field survival (r = 0.71, p = 0.048), supporting a nursery-to-field carry-over effect. The findings highlight rooting space as a leverage point for improving reforestation outcomes.

Teak plantations are widely promoted as productive forest systems with potential contributions to carbon storage and climate-oriented land management. However, plantation carbon estimates often rely on generic biomass-to-carbon conversion factors, which may overlook variation in carbon concentration among tree components. This study refined carbon estimates in tropical teak plantations in Nayarit, western Mexico, by combining pantropical allometry with measured carbon fractions. Carbon concentration was determined in leaves, branches, stem, roots, and total biomass, and carbon stocks were compared using the generic 0.47 factor and measured total biomass carbon fractions. Carbon concentration differed among biomass components, with leaves and branches remaining below 47%, while stem, roots, and total biomass exceeded this value. The measured total biomass carbon fraction averaged 48.24%, producing refined carbon estimates that were consistently higher than those obtained with the generic factor. Across plantation-age records, the refined approach increased carbon estimates by 1.33 Mg C ha⁻¹, equivalent to a mean relative adjustment of 2.67%. When projected as an illustrative scenario, this difference represented 133, 665, and 1330 Mg C over 100, 500, and 1000 ha, respectively. These findings show that measured carbon fractions can reduce one source of conversion-related uncertainty and refine plantation-level carbon estimates. Broader regional application would require larger and more representative plantation inventories.

This study examined the floristic composition, structural attributes, productivity, biomass, and conservation value of a tropical rainforest (TRF) in the Colombian Pacific region. A complete inventory of trees with DBH (Diameter at Breast Height) ≥ 10 cm was conducted, and analyses included diversity indices, species accumulation and rarefaction curves, structural parameters, productivity indices, and estimates of aboveground biomass and C (carbon) stocks. Multivariate analyses were also applied to evaluate beta diversity and flo-ristic dissimilarity among plots. The forest showed high species richness, with 45 species belonging to 26 families, and diversity indices confirmed a heterogeneous and balanced community. Structural analyses revealed a dense and complex stand with continuous re-generation, a reverse-J diameter distribution, and stratification dominated by lower and middle layers. Productivity indices highlighted the dual contribution of abundant small stems and a smaller number of dominant trees. Aboveground biomass reached very high values, corresponding to substantial C storage, with most of the pool concentrated in a few dominant taxa. Conservation analysis revealed that while most species were classified as Least Concern, four taxa were identified as threatened or vulnerable, and several remained unevaluated. Overall, the results confirm the dual role of TRFs as biodiversity hotspots and critical C reservoirs, underscoring the need for integrated conservation strategies.

Alluvial gold mining can alter Amazonian tree communities, but its association with medicinal tree diversity, structure, and carbon stocks remains poorly documented. We compared four 1-ha forest plots in Boca Colorado, Madre de Dios, Peru: two with greater evidence of mining intervention and two less-impacted plots. All medicinal trees with DBH ≥ 10 cm were inventoried, and taxon richness, Hill diversity, rarefaction, floristic dissimilarity, dominance, structural attributes, and biomass carbon were evaluated. A total of 1344 individuals representing 203 taxa were recorded. Mean plot-level richness was higher in less-impacted forests than in impacted forests (135.5 vs. 95.5 taxa), as were diversity of orders q = 1 (79.9 vs. 48.1) and q = 2 (38.7 vs. 23.6). Richness therefore showed a scale-dependent pattern: less-impacted plots were richer individually, whereas impacted forests accumulated more taxa when plots were pooled (172 vs. 143), reflecting greater among-plot differentiation. Turnover accounted for 79.5% of Jaccard dissimilarity. Less-impacted forests also had 16.1% higher stem density and 47.1% higher total biomass carbon, with the carbon contrast supported by the hierarchical bootstrap analysis (p = 0.043). These findings indicate that mining intervention was associated with differences in abundance distribution, floristic composition, forest structure, and carbon stocks that were not captured by pooled richness alone.