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Amazon forest management plans have a variety of effects on carbon emissions, both positive and negative. All of these effects need to be quantified to assess the role of this land use in climate change. Here, we contribute to this effort by evaluating the carbon stocks in logs and timber products from an area under forest management in the southeastern portion of Acre State, Brazil. One hundred and thirty-six trees of 12 species had DBH ranging from 50.9 cm to 149.9 cm. Basic wood density ranged from 0.3 cm−3 to 0.8 g cm−3 with an average of 0.6 g cm−3. The logs had a total volume of 925.2 m3, biomass of 564 Mg, and carbon stock of 484.2 MgC. The average volumetric yield coefficient (VYC) was 52.3% and the carbon yield coefficient (CYC) was 53.2% for logs of the 12 species. The sawn-wood products had a total volume of 484.2 m3, biomass of 302.6 Mg, and carbon stock of 149.9 MgC. Contributions of the different species to the total carbon stored in sawn-wood products ranged from 2.2% to 21.0%. Means and standard deviations for carbon transferred to sawn-wood products per-species from the 1252.8-ha harvested area ranged from 0.4 ± 1.1 MgC to 2.9 ± 0.4 MgC, with the largest percentages of the total carbon stored in wood products being from Dipteryx odorata (21.0%), Apuleia leiocarpa (18.7%), and Eschweilera grandiflora (11.7%). A total of 44,783 pieces of sawn lumber (such as rafters, planks, boards, battens, beams, and small beams) was obtained from logs derived from these trees. Lumber production was highest for boards (54.6% of volume, 47.4% of carbon) and lowest for small beams (1.9% of volume, 2.3% of carbon). The conversion factor for transforming log volume into carbon stored in sawn-wood products was 16.2%. Our results also show that species that retain low amounts of carbon should be allowed to remain in the forest, thereby avoiding low sawmill yield (and consequent generation of waste) and allowing these trees to continue fulfilling environmental functions.

Tropical forest management has both positive and negative effects on climate change, and quantifying these effects is important both to avoid or minimize negative impacts and to reward net positive effects. This study contributes to this effort by estimating the aboveground volume and carbon present in commercial tree species in a managed forest in the forest harvest stage in Brazil’s state of Acre. A total of 12,794 trees of commercial species were measured. Trees were categorized and quantified as: “harvested trees” (“harvest or cut”), which were felled in the harvest stage, and “remaining trees” (“future cutting,” “trees in permanent protection areas or APPs,” “seed trees,” “rare trees” and “trees protected by law”) that remained standing in the forest post-harvest. Aboveground volume and carbon stocks of the 81 commercial species (diameter at breast height [DBH] ≥ 10 cm) totaled 79.19 m³ ha−1 and 21.54 MgC ha−1, respectively. The category “harvested trees” represents 44.48% and “remaining trees” 55.49% of the aboveground volume stocks. In the managed area, the category “harvested trees” is felled; this is composed of the commercial bole that is removed (19.25 m³ ha−1 and 5.32 MgC ha−1) and the stump and crown that remain in the forest as decomposing organic material (15.97 m³ ha−1 and 4.41 MgC ha−1). We can infer that the 21.54 MgC ha−1 carbon stock of standing commercial trees (DBH ≥ 10 cm) represents 13.20% of the total aboveground carbon in the managed area. The commercial boles removed directly from the forest represent 3.26% of the total aboveground carbon, and the stumps and crowns of the harvested trees represent the loss of an additional 2.70%. For sustainability of the management system in terms of carbon balance, growth in the 35-year management cycle must be sufficient to replace not only these amounts (0.27 MgC ha−1 year−1) but also losses to collateral damage and to additional logging-related effects from increased vulnerability to forest fires. Financial viability of future management cycles will depend on replenishment of commercial trees of harvestable size (DBH ≥ 50 cm).

Forest restoration in Brazil has gained relevance in the country’s environmental agenda, due to the need for forest recovery of large liabilities of existing forests and participation in several international vegetation restoration agreements. However, forest restoration management faces challenges, it being necessary to create a database of species-level performances to increase the success of these projects. The objective was to evaluate the survival and growth of five Atlantic Forest native species (Anadenanthera macrocarpa; Ceiba speciosa; Cytharexyllum myrianthum; Hymenaea courbaril; and Peltophorum dubium) in plastic bags (1177 cm3) and tubes (180 cm3). Ninety seedlings (18 of each species) were planted per container. Plant performance in the field consisted of evaluating the increase in the diameter and height of seedlings of the native forest species. Diameter at soil level (DSL) and plant height (H) were measured at 42 months after transplanting, and the monthly periodic increments (MPI) of the DSL and H were calculated. Plant survival (SV) of seedlings was affected by the type of container, registering the highest SV rates in those planted in plastic bags. Cytharexyllum myrianthum and H. courbaril presented high SV rates in tubes. The growth rate of the species at 42 months differed according to the containers tested. Cytharexyllum myrianthum presented the lowest SV rates (16.7–27.8%), regardless of the container used in this experiment. Ceiba speciosa was sensitive to the reduction in size of the container, showing low SV in tubes (27%) compared with plastic bags (61%); i.e., this species did not tolerate conditions with root growth restriction. Anadenathera macrocarpa and H. courbaril showed no differences in SV, regardless of the container used. The results assist the production of native species of the Atlantic Forest, reinforcing the need to understand performances in the field at the species level.

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Gilbués é o maior núcleo de desertificação dos quatro existentes no Brasil, com intensa degradação ambiental. Por meio deste estudo objetivou-se mapear as áreas prioritárias a conservação em função da declividade do terreno no núcleo de desertificação de Gilbués, Piauí, ponderando-se que o fator declividade é considerado sítio geomorfologicamente frágil, sobretudo sob pressão antrópica no uso dos recursos destes espaços. A delimitação das áreas de encostas prioritárias a conservação, conforme o Novo Código Florestal Brasileiro, foi realizada com auxílio do Software ArcGIS 10.0, utilizando-se de imagens da base SRTM no formato raster para compor o Modelo Digital de Elevação Hidrologicamente Consistente (MDEHC) e de planos de informações de hipsometria, declividade do terreno, classes de solos, índice de vegetação, geologia, além de análise de imagens de satélite. Quantificou-se 19,5 km² de sítios classificados como Áreas de Uso Restrito (AUR). Não foram constatadas áreas do tipo APP de encostas de morros (>45°).

RESUMO Objetivou-se avaliar a sobrevivência e o crescimento de espécies nativas, no período de 20 meses, em plantio de recuperação de uma área degradada em Viçosa, Minas Gerais. O estudo foi conduzido na área denominada Espaço Aberto de Eventos da Universidade Federal de Viçosa (UFV), em Viçosa, Minas Gerais. O plantio foi realizado em dezembro de 2013, em uma área de 0,25 ha, com combinação de espécies florestais nativas da Mata Atlântica. Foram plantadas 500 mudas, no espaçamento 2 m x 2 m, em Delineamento em Blocos Casualizados (DBC), sendo cada bloco constituído de 25 espécies. Foram mensuradas a altura e o diâmetro ao nível do solo. Observou-se um índice geral de sobrevivência de 50,4%. Dentre as espécies analisadas, a Schinus terebinthifolius, Sapindus saponaria, Plathymenia reticulata, Cassia grandis e Senna multijuga são recomendadas para plantios mistos de recuperação de áreas degradadas em situações similares à do experimento. As espécies Plathymenia reticulata e Senna multijuga, além do sucesso de sobrevivência, tiveram destaque nos parâmetros de crescimento. Assim, o estudo possibilita inferir a respeito da potencialidade e restrição de espécies florestais no plantio de recuperação da área degradada na Mata Atlântica.