ABSTRACT
The Tectona grandis L.f. (teak) is an important forest species with high economy value in Asia, Africa, and Latin America. In Latin America, Brazil is one of the countries with the most cultivated areas. The cultivation of teak turns out to be challenging because of its high nutritional demand and the need for seedling production by clonal propagation that includes about 90 days in the nursery phase. The optimization of seedling production is necessary for better results in the nursery and to enhance growth in the field. In this way, the well-known advantage of using microorganisms that promote plant development appears as a potential biotechnological approach to be explored and for the implantation of new areas of wood production. In this study, the inoculation of Bacillus subtilis as plant growth-promoting rhizobacteria (PGPR) was evaluated, and Rhizophagus clarus, an arbuscular mycorrhizal fungus (AMF), and the co-inoculation of these microorganisms in the teak seedling production phase can improve the development of commercial plantations under field conditions. Experiments were carried out under greenhouse and field conditions to evaluate four treatments based on the substrate inoculation of the seedlings. Treatments consisted of a non-inoculated control, PGPR inoculation, AMF inoculation, and PGPR + AMF inoculation. The results of the biometric evaluation of seedlings in the greenhouse showed that there was a significant difference in AMF inoculation and PGPR + AMF inoculation in terms of the specific root length and root density treatments, there was also a positive correlation between these two treatments and the absorption of some nutrients, such as P, N, K, Mg, Cu, Mn, and Zn. This response led to an increase between 4.75 and 11.04% in the field growth rate.
ABSTRACT
Plantation forestry, in which trees are grown as a crop, must maintain wood production over repeated harvest cycles (rotations) to meet global wood demands on a limited land area. We analyze 33 yr of Landsat observations across the world's most productive forestry system, Eucalyptus plantations in southeastern Brazil, to assess long-term regional trends in wood production. We apply a simple algorithm to time series of the vegetation index NIRv in thousands of Eucalyptus stands to detect the starts and ends of rotations. We then estimate wood production in each identified stand and rotation, based on a statistical relationship between NIRv trajectories and inventory data from three plantation companies. We also compare Eucalyptus NIRv with that of surrounding native vegetation to assess the relative influence of management and environment on plantation productivity trends. Across more than 3,500 stands with three complete rotations between 1984 and 2016, modeled wood volume decreased significantly between the first and second rotation, but recovered at least partially in the third; mean wood volumes for the three rotations were 262, 228, and 247 m3 /ha. This nonlinear trend reflects intensifying plantation management, as rotation length decreased by an average of 15% (decreasing wood volume per rotation) and NIRv proxies of tree growth rates increased (increasing volume) between the first and third rotation. However, NIRv also increased significantly over time in unmanaged vegetation around the plantations, suggesting that environmental trends affecting all vegetation also contribute to sustaining wood production. Management inputs will likely continue to be important for maintaining wood production in future harvests.
Subject(s)
Eucalyptus , Brazil , Forestry , Trees , WoodABSTRACT
Air pollution is considered to be one of the main causes of forest decline. The cambium is responsible for increase in tree girth, and its functioning is determined by environmental pressures. This study compared cambium histology of Ceiba speciosa (A. St.-Hil.) Ravenna (Malvaceae) in polluted and preserved sites in the Atlantic Rainforest domain. Samples were obtained during periods of cambial activity and dormancy and were processed and examined according to standard light microscopy techniques. In addition to differences typically observed in cambium during periods of activity and dormancy, the fusiform initials were shorter in trees of the polluted site. Furthermore, cambial rays were shorter, but larger, in the polluted site. It should be noted that all parameters related to cambial rays showed significant differences between the study sites. This is the first report of the effects of pollution on cambial activity in a South American species. The results suggest a tolerance of C. speciosa to pollution and reveal this species to be an important biomarker for environmental monitoring studies.
Subject(s)
Cambium/anatomy & histology , Ceiba/drug effects , Environmental Pollution , Brazil , Cambium/drug effects , Ceiba/anatomy & histology , Cities , Environmental Monitoring , TreesABSTRACT
Foram avaliadas espécies florestais nativas e exóticas em duas condições de plantio: a pleno sol e em faixas de enriquecimento de capoeira, a fim de gerar tecnologias para incorporação ao processo produtivo de áreas alteradas na região amazônica para minimizar a pressão do desmatamento sobre a floresta natural. Os dados analisados (DAP, altura, volume por hectare e sobrevivência) referem-se à idade de seis anos. No plantio a pleno sol, a espécie que apresentou o melhor desempenho foi Ceiba pentandra, com médias de DAP de 19,6 cm, altura de 10,2 m e volume de 390,9 m³ ha-1. Hymenaea courbaril também apresentou crescimento satisfatório, com médias de 11,5 cm de DAP, 10,8 m de altura e 144,8 m³ ha -1 de volume. Nos plantios de enriquecimento de capoeira, a Carapa guianensis foi a espécie que apresentou o melhor desempenho, com 8,3 cm de DAP, 6,4 m de altura e volume de 54,8 m³ ha -1. Acacia mangium e Sclerolobium paniculatum apresentaram crescimento superior, mas as taxas de sobrevivência foram muito baixas nas duas condições de plantio.
This work evaluated exotic and native forest species in two plantation conditions: full sun and secondary forest enrichment strips, for generating technologies into incorporate to the productive process of degraded lands in the Amazonian region, to minimize the deforestation pressure on the natural forest. The analyzed data (DBH, height, volume per hectare and survival) refers to six years old species. In the full sun plantation, the species that presented the best performance was Ceiba pentandra, with means: DBH of 19.6 cm, height of 10.2 m and volume of 390.9 m³ ha-1. Hymenaea courbaril also presented satisfactory growth, with means: DBH of 11.5 cm, height of 10.8 m and volume of 144.8 m³ ha-1. In the secondary forest enrichment plantation, Carapa guianensis was the species that presented the best performance, with means: DBH of 8.3 cm, height of 6.4 m and volume of 54.8 m³ ha-1. Acacia mangium and Sclerolobium paniculatum presented better growth. However, the survival rates were very low in both plantations.
Subject(s)
Lumber Industry , Forests , Biomass , Ceiba , Hymenaea , Brazil , Amazonian Ecosystem , GrowthABSTRACT
This work evaluated exotic and native forest species in two plantation conditions: full sun and secondary forest enrichment strips, for generating technologies into incorporate to the productive process of degraded lands in the Amazonian region, to minimize the deforestation pressure on the natural forest. The analyzed data (DBH, height, volume per hectare and survival) refers to six years old species. In the full sun plantation, the species that presented the best performance was Ceiba pentandra, with means: DBH of 19.6 cm, height of 10.2 m and volume of 390.9 m³ ha-1. Hymenaea courbaril also presented satisfactory growth, with means: DBH of 11.5 cm, height of 10.8 m and volume of 144.8 m³ ha-1. In the secondary forest enrichment plantation, Carapa guianensis was the species that presented the best performance, with means: DBH of 8.3 cm, height of 6.4 m and volume of 54.8 m³ ha-1. Acacia mangium and Sclerolobium paniculatum presented better growth. However, the survival rates were very low in both plantations.
Foram avaliadas espécies florestais nativas e exóticas em duas condições de plantio: a pleno sol e em faixas de enriquecimento de capoeira, a fim de gerar tecnologias para incorporação ao processo produtivo de áreas alteradas na região amazônica para minimizar a pressão do desmatamento sobre a floresta natural. Os dados analisados (DAP, altura, volume por hectare e sobrevivência) referem-se à idade de seis anos. No plantio a pleno sol, a espécie que apresentou o melhor desempenho foi Ceiba pentandra, com médias de DAP de 19,6 cm, altura de 10,2 m e volume de 390,9 m³ ha-1. Hymenaea courbaril também apresentou crescimento satisfatório, com médias de 11,5 cm de DAP, 10,8 m de altura e 144,8 m³ ha -1 de volume. Nos plantios de enriquecimento de capoeira, a Carapa guianensis foi a espécie que apresentou o melhor desempenho, com 8,3 cm de DAP, 6,4 m de altura e volume de 54,8 m³ ha -1. Acacia mangium e Sclerolobium paniculatum apresentaram crescimento superior, mas as taxas de sobrevivência foram muito baixas nas duas condições de plantio.