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New Publication Highlights
2025 Summary Now Available!
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Brazilian Eucalyptus and Pinus forests are the most productive forests worldwide. The growth rates of these intensively managed plantations depend strongly on environmental conditions and matching genotypes to local environments. Changing climates underscore the value of understanding the intricacies of how these plantations can fix high amounts of carbon (C) and grow so much wood. We measured the full C budgets of Eucalyptus and Pinus forests across climate gradients in Brazil, focusing on the rates of C uptake, the allocation of C to belowground roots and mycorrhizae, and stem growth. We found that gross primary production (GPP) varied more than sixfold across the climate conditions in Brazil. Maximum temperature was the main climatic driver of productivity, where extreme temperatures reduced fluxes to stem production while increasing fluxes to root production. Net ecosystem production varied with management and age across the sites. The ecophysiological investigation presented in this work is fundamental for understanding C partitioning behavior under extreme temperature conditions. In this way, our results provide tools for forest managers to support their decision-making processes as well as starting points for strategies to be implemented in projects aimed at mitigating the effects of climate change.
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Fernanda Leite Cunha:
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Cunha FL, Campoe OC, de Souza CR, Leite e Lopes I, Nouvellon YN, Albaugh T, Carter DR, Rubilar R, Deliberari I, Cook R, Guillemot J, Le Maire G, Laclau JP, Stape JL, Alvares CA. 2026. Carbon fluxes and partitioning in Eucalyptus and Pinus plantations across a climatic gradient in Brazil. Agricultural and Forest Meteorology. 378: 110977. DOI: https://doi.org/10.1016/j.agrformet.2025.110977
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Gross primary production
Carbon sequestration
Carbon allocation
Belowground allocation
Wood productivity
Thermal stress
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Pinus taeda is a species native to southeastern regions of the United State (USA), but plantations with the highest productivity are found in the southern region of Brazil (BRA). The objective of our study was to determine the higher (Light Use Efficiency) LUE and absorbed photosynthetically active radiation (APAR) of P. taeda genotypes with different spacings in order to evaluate potential strategies that could increase the productivity of intensively managed stands in Brazil and the United States. The experiment was designed as a split-split-plot, and evaluations included 81 trees in BRA and 63 trees in the USA, two genotypes (clone C3 vs. open pollination (OP)) and two spacings (BRA – 2.4 × 6.8 m, 613 trees/ha; USA – 3.66 × 4.42 m, 618 trees/ha) and narrow spacing (BRA – 2.4 × 2.2 m, 1894 trees/ha; USA – 3.66 × 1.47 m, 1853 trees/ha). Individual tree calculations of LUE were made at both locations for each tree by dividing its current annual stem increment (WNPPi) by APAR estimated from MAESTRA, a process-based model. The parameterization of this model included the use of forest inventory data, meteorological data, crown characteristics (average crown radius, height, diameter, and leaf area), leaf area density distribution, leaf transmittance, and leaf and soil reflectance. Results showed that trees growing in Brazil had greater leaf area (32%) and stem biomass growth (5%) and absorbed more light (49%) than trees in the USA. The genotype C3 was more efficient than OP in light use at both locations. Narrow spacing resulted in higher LUE values (0,8 g MJ-1). APAR explain 80% and 65% of WNPP in BRA and USA, respective. Our results suggest that LUE explained the growth differences between sites, genotypes, and spacings, while APAR provided a better differentiation of WNPP between the sites.
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Lorena Oliveira Barbosa:
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Barbosa LO, Campoe OC, Scolforo JRS, Scolforo HF, Albaugh TJ, Cook R, Rubilar R, Santos JA. 2026. APAR is a better predictor than LUE of the stem growth differences found between Loblolly pine grown in the United Stated and Brazil. Agricultural and Forest Meteorology. 378: 110964. DOI: https://doi.org/10.1016/j.agrformet.2025.110964
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Process-based models
MAESTRA
Production ecology
Net primary productivity
Pinus taeda
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Absorbed photosynthetically active radiation explains differences in juvenile Pinus taeda growth.
Genotypes and spacing influences the amount of photosynthetically active radiation absorbed by trees.
Light use efficiency does not explain the difference between the growth of native and exotic Pinus taeda.
Trees with wide spacing had greater leaf area, greater light absorption and greater stem biomass.
The clonal genotype was more efficient in light use at the narrow spacing than the open-pollinated variety in Brazil.
