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Maximizing initial aboveground woody biomass (AGB) accumulation in order to obtain early payments for carbon stocking is essential for the financial viability of reforestation programs fostered by climate mitigation efforts. Intensive silviculture, i.e., silviculture traditionally used in commercial forestry to maximize productivity and gains, has recently been advocated as a promising approach to enhance AGB accumulation in restoration plantations. However, this approach may hamper natural forest regeneration and ecological succession due to high competition between colonizing plants and planted trees. We investigated the impacts of different silvicultural treatments applied to restoration plantations with 20 native tree species on AGB accumulation and spontaneous regeneration of native woody species in an experiment set up in the Atlantic Forest of Brazil. Intensive silviculture demonstrated a remarkable potential to enhance AGB accumulation in restoration plantations by increasing up to three times the AGB of tree stands (from ~25 to 75 Mg/ha in the 12th year). Intensive fertilization/weed control enhanced AGB accumulation, while higher tree density and the proportion of pioneers did not have a significant effect on AGB over the time. In spite of higher costs (cost increase of 13–19%), the cost‐effectiveness for AGB accumulation of intensive silviculture was comparable to that of traditional silviculture applied to restoration (US$50–100/Mg AGB for 3 × 2 m spacing). Contrary to our expectations, we did not find a trade‐off between AGB accumulation by planted trees and the spontaneous regeneration of tree species, since intensive silviculture enhanced the regeneration of both planted (total of 12 species) and colonizing woody species (total of 30 species) in the plantation understory. Specifically, a strong association was found between AGB stocks and the abundance and richness of colonizing species, a vast majority of which (90% of species and 95% of individuals) were dispersed by animals. We report a case of positive correlation between AGB stocking and woody species regeneration in the restoration of the Atlantic Forest. Fostering the establishment and maintenance of restoration tree plantations can, in some cases, be a win‐win strategy for climate mitigation and biodiversity conservation in human‐modified tropical landscapes.

International forest landscape restoration commitments have promoted the restoration of millions of hectares of degraded and deforested lands globally, but few forest restoration approaches provide both ecologically‐sound and financially‐viable solutions for achieving the spatial scale proposed. One potential revenue source for restoration is selective harvesting of timber, a product for which there is a clear global market and increasing demand. The use of commercially valuable exotic trees may attract farmers to restoration, but can be a major concern for ecologists. Here, we present results collected over 7 years from experimental studies at three sites across the Brazilian Atlantic Forest to assess the impacts of incorporating exotic eucalypts as a transitional stage in tropical forest restoration on above‐ground biomass accumulation, native woody species regeneration and financial viability. Biomass accumulation was nine times greater in mixed eucalypt‐native species plantations than native only plantings due to fast eucalypt growth. Nonetheless, the growth of native non‐pioneer trees was not affected or only slightly reduced by eucalypts prior to logging. Eucalypts did not negatively affect the natural regeneration of native woody species before or after eucalypt logging. Canopy cover regrew quickly but was slightly lower a year following logging in mixed eucalypt‐native species plantations. Natural regeneration richness and planted non‐pioneer growth were similar across treatments in the post‐logging period. We found higher variation of biomass accumulation and native species regeneration among sites than between plantation types within sites. The income from eucalypt wood production offset 44%–75% of restoration implementation costs. Synthesis and applications. Many of the negative effects attributed to eucalypts on the growth and natural regeneration of native trees depend on features of the production system, landscape structure, soil, and climate in which they are grown, rather than the effects of eucalypts per se. In Brazil's Atlantic Forest region, exotic eucalypts can become important allies of tropical forest restoration, and their use and investment opportunities should be considered within the portfolio of options supported by public and private funding and policies.

One of the most intriguing questions in plant ecology is which evolutionary strategy allows widely distributed species to increase their ecological range and grow in changing environmental conditions. Phenotypic plasticity and local adaptations are major processes governing species range margins, but little is known about their relative contribution for tree species distribution in tropical forest regions. We investigated the relative role of phenotypic plasticity and local adaptation in the ecological distribution of the widespread palm Euterpe edulis in the Brazilian Atlantic Forest. Genetic sampling and experiments were performed in old‐growth remnants of two forest types with higher (Seasonal Semideciduous Forests vs. Submontane Rainforest) and lower biogeographic association and environmental similarities (Submontane Rainforest vs. Restinga Forest). We first assessed the molecular genetic differentiation among populations, focusing on the group of loci potentially under selection in each forest, using single‐nucleotide polymorphism (SNPs) outliers. Further, we looked for potential adaptive divergence among populations in a common garden experiment and in reciprocal transplants for two plant development phases: seedling establishment and sapling growth. Analysis with outlier loci indicated that all individuals from the Semideciduous Forest formed a single group, while another group was formed by overlapping individuals from Submontane Rainforest and Restinga Forest. Molecular differentiation was corroborated by reciprocal transplants, which yielded strong evidence of local adaptations for seedling establishment in the biogeographically divergent Rainforest and Semideciduous Forest, but not for Restinga Forest and Submontane Rainforest. Phenotypic plasticity for palm seedling establishment favors range expansion to biogeographically related or recently colonized forest types, while persistence in the newly colonized ecosystem may be favored by local adaptations if climatic conditions diverge over time, reducing gene flow between populations. SNPs obtained by next‐generation sequencing can help exploring adaptive genetic variation in tropical trees, which impose several challenges to the use of reciprocal transplants.

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Species Site Growth Form d' Abuta selloana rainforest Liana 0.37101959 Acacia sp rainforest Liana 0.66863964 Acacia tenuifolia rainforest Liana 0.64563236 Adenocalymma comosum rainforest Liana 0.35056997 Adenocalymma sp rainforest Liana 0.24733598 Anthodon cf decussatum rainforest Liana 0.58943397 Aristolochia paulistana rainforest Liana 0.72256301 Arrabidaea sp rainforest Liana 0.39238059 Bauhinia microstachya var microstachya rainforest Liana 0.52799252 Bauhinia surinamensis rainforest Liana 0.33653056 cf Pfaffia paniculata rainforest Liana 0.32867373 Cheiloclinium serratum rainforest Liana 0.34434195 Chondodendron platyphyllum rainforest Liana 0.23281347 Cissampelos fasciculata rainforest Liana 0.34434195 Cissus paullinifolia rainforest Liana 0.58859191 Coccoloba sp rainforest Liana 0.40974170 Condylocarpon ishtmicum rainforest Liana 0.23670242 Dalbergia frutescens rainforest Liana 0.35037888 Dalbergia lateriflora rainforest Liana 0.02131419 Dioclea sp rainforest Liana 0.50366403 Elachyptera micrantha rainforest Liana 0.38572878 Forsteronia australis rainforest Liana 0.25485972 Forsteronia refracta rainforest Liana 0.23625529 Forsteronia sp2 rainforest Liana 0.23682616 Heteropsis rigidifolia rainforest Liana 0.35450574 Heteropterys nitida rainforest Liana 0.39416773 Heteropterys sp rainforest Liana 0.09858390 Hippocratea nervosa rainforest Liana 0.76852640 Hiraea sp rainforest Liana 0.32539831 Hyperbaena domingensis rainforest Liana 0.51713840 icacinaceae sp rainforest Liana 0.58057770 Macfadyena uncata rainforest Liana 0.46678568 Machaerium declinatum rainforest Liana 0.46192651 Machaerium dimorphandrum rainforest Liana 0.59128053 Machaerium lanceolatum rainforest Liana 0.50984505 Machaerium uncinatum rainforest Liana 0.48928031 Marcgravia polyantha rainforest Liana 0.44654727 Mendoncia velloziana rainforest Liana 0.31288364 Mikania lundiana rainforest Liana 0.38490971 Mikania sp1 rainforest Liana 0.23977379 Paragonia sp rainforest Liana 0.34434195 Passiflora sidaefolia rainforest Liana 0.29853445 Paullinia bicorniculata rainforest Liana 0.57670049 Paullinia carpopodea rainforest Liana 0.29449520 Paullinia seminuda rainforest Liana 0.91045379 Paullinia spicata rainforest Liana 0.54198647 Paullinia trigonia rainforest Liana 0.23273036

Lianas play a key role in forest structure, species diversity, as well as functional aspects of tropical forests. Although the study of lianas in the tropics has increased dramatically in recent years, basic information on liana communities for the Brazilian Atlantic Forest is still scarce. To understand general patterns of liana abundance and biomass along an elevational gradient (0–1,100 m asl) of coastal Atlantic Forest, we carried out a standard census for lianas ≥1 cm in five 1‐ha plots distributed across different forest sites. On average, we found a twofold variation in liana abundance and biomass between lowland and other forest types. Large lianas (≥10 cm) accounted for 26–35% of total liana biomass at lower elevations, but they were not recorded in montane forests. Although the abundance of lianas displayed strong spatial structure at short distances, the present local forest structure played a minor role structuring liana communities at the scale of 0.01 ha. Compared to similar moist and wet Neotropical forests, lianas are slightly less abundant in the Atlantic Forest, but the total biomass is similar. Our study highlights two important points: (1) despite some studies have shown the importance of small‐scale canopy disturbance and support availability, the spatial scale of the relationships between lianas and forest structure can vary greatly among tropical forests; (2) our results add to the evidence that past canopy disturbance levels and minimum temperature variation exert influence on the structure of liana communities in tropical moist forests, particularly along short and steep elevational gradients.