163 resultados para tree height growth
em Repositório Institucional UNESP - Universidade Estadual Paulista "Julio de Mesquita Filho"
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Lepidopteran pests have occurred in eucalyptus plantations in Brazil since 1948, reaching high population levels, reducing tree growth and causing considerable losses in wood production. The control of defoliating caterpillars in eucalyptus forests is complex, mainly due to the large extent of forest plantations and tree height, necessitating the aerial application of chemical or biological insecticides. Due to this complexity, alternative control methods have been proposed, for instance biological control through the use of parasitoids. Trichospilus diatraeae Cherian & Margabandhu, 1942 is a gregarious pupal parasitoid that preferentially attacks species of the order Lepidoptera. This is the first report of T. diatraeae parasitizing pupae of the eucalyptus defoliator Euselasia eucerus Hewitson in Brazil. This parasitoid offers new perspectives for the biological control programmes of this species in eucalyptus plantations in Brazil.
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Forest dynamics will depend upon the physiological performance of individual tree species under more stressful conditions caused by climate change. In order to compare the idiosyncratic responses of Mediterranean tree species (Quercus faginea, Pinus nigra, Juniperus thurifera) coexisting in forests of central Spain, we evaluated the temporal changes in secondary growth (basal area increment; BAI) and intrinsic water-use efficiency (iWUE) during the last four decades, determined how coexisting species are responding to increases in atmospheric CO2 concentrations (Ca) and drought stress, and assessed the relationship among iWUE and growth during climatically contrasting years. All species increased their iWUE (ca. +15 to +21 %) between the 1970s and the 2000s. This increase was positively related to Ca for J. thurifera and to higher Ca and drought for Q. faginea and P. nigra. During climatically favourable years the study species either increased or maintained their growth at rising iWUE, suggesting a higher CO2 uptake. However, during unfavourable climatic years Q. faginea and especially P. nigra showed sharp declines in growth at enhanced iWUE, likely caused by a reduced stomatal conductance to save water under stressful dry conditions. In contrast, J. thurifera showed enhanced growth also during unfavourable years at increased iWUE, denoting a beneficial effect of Ca even under climatically harsh conditions. Our results reveal significant inter-specific differences in growth driven by alternative physiological responses to increasing drought stress. Thus, forest composition in the Mediterranean region might be altered due to contrasting capacities of coexisting tree species to withstand increasingly stressful conditions. © 2013 Springer-Verlag Berlin Heidelberg.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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The present work aimed to evaluate the effects of simulated drift of glyphoste on Eucalyptus grandis, through the application of low doses in different parts of the plant. The experimental design was a randomized block design with five replications. The treatments were glyphosate application at 0; 30; 60; 90 e 120 g a.e. ha(-1) of the commercial formulation Scout (R). Three forms of application were used: applying on leaf, on stem, and on the entire plant (leaf + stem). For leaf application, stems were covered with plastic ribbons to protect them from the solution; the same was made with plants that were sprayed on stems, covering leaf with plastic bag. The application was carried out in an armed stationary spray tips XR 11002 VS, with 183 KPa pressure in volume of 200 L ha(-1). The eucalyptus plants receiving applications in leaves and whole plant (leaves + stem) showing effects of intoxication are more intense about the plants that received the stem applications only. However, there may be increases in height growth and total dry mass of eucalyptus plants in applications of 30 g a.e. ha(-1) glyphosate.
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As part of a larger study evaluating several silvicultural techniques for restoring tropical moist forests on abandoned agricultural lands in southeastern Brazil, direct seeding with five early-successional Atlantic forest species was tested at three degraded sites, characterized by different soil types and land-use histories, within the Environmental Protection Area at Botucatu, SP. The species used in this study were Chorisia speciosa, Croton floribundus, Enterolobium contorstisiliquum, Mimosa scabrella, and Schizolobium parahyba. Scarified seeds of each of these species were sown in prepared seed spots in replicated, 0.25 ha mixed-species plots at an initial espacement of 1 m x 1 m at each site. of the five species planted, only two, Enterolobium and Schizolobium, showed good seed germination, seedling survival, and early growth rates, averaging 4.1-4.6 cm stem diameter and 1.5-1.7 m height growth during the first 2 years after sowing. These two species constituted 88-100% of the total stand density, which ranged from 1050 to 1790 stems ha(-1) at 2 years. Despite the poor performance of the other species tested, we observed that the natural regeneration of native forest species originating from remnant forests in the general vicinity of our study sites was significantly greater within the direct-seeded plots than in unplanted control plots that were protected from fire and other disturbances. Published by Elsevier B.V. B.V.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Aboveground biomass predictive equations were developed for a highly productive 47-year-old mixed Douglas-fir and western hemlock stand in southwest Washington State to characterize the preharvest stand attributes for the Fall River Long-Term Site Productivity Study. The equations were developed using detailed biomass data taken from 31 Douglas-fir and 11 western hemlock trees within the original stand. The stand had an average of 615 live trees per hectare, with an average dbh of 35.6 cm (39.1 cm for Douglas-fir and 33.3 cm for western hemlock) and an average total tree height of 31.6 m (32.8 m for Douglas-fir and 30.2 m for western hemlock). Equations developed were of the form In Y = b(1) + b(2) In dbh, where Y = biomass in kg, dbh = diameter in cm at 1.3 m height, b(1) = intercept, and b(2) = slope of equation. Each tree part was estimated separately and also combined into total aboveground biomass. The total aboveground biomass estimation equations were In Y = -0.9950 + 2.0765 In dbh for Douglas-fir, and In Y = -1.6612 + 2.2321 In dbh for western hemlock. The estimate of the aboveground live-free biomass was of 395 Mg ha(-1) (235 Mg ha(-1) for Douglas-fir and 160 Mg ha(-1) for western hemlock), with 9.5, 29.3, 12.9, 308, and 32.7 Mg ha(-1) in the foliage, live branches, dead branches, stem wood, and stem hark, respectively. When compared with biomass estimates from six other studies, ranging in age from 22 to 110 years and from 96.3 to 636 Mg ha(-1), the biomass of the Fall River site was relatively high for its age, indicating very high productivity.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Flexibilidade anterior do tronco (FAT) é um componente importante dos exames clínico e de aptidão física utilizado como indicador da função vertebral. O teste mais utilizado para sua quantificação é o sentar-e-alcançar (TSA), que considerara como padrão de normalidade o toque das mãos nos pés, com critérios e parâmetros de análise que independem das variáveis. Neste estudo, investigou-se a FAT em adolescentes, após o pico da velocidade de crescimento em estatura, em função do sexo, da velocidade de execução e dos dados antropométricos. Os índices foram obtidos em centímetros; o peso corporal em kg. Participaram 102 adolescentes, sendo 45 mulheres e 57 homens, entre 16 e 20 anos de idade. Resultados indicam que o fator sexo, dados antropométricos e a velocidade de execução do teste influenciam os índices de flexibilidade; a avaliação da função vertebral não pode ter como critério de normalidade atingir os pés pelo TSA, e que a velocidade rápida leva a melhores resultados. em resumo, os resultados indicam que tocar os pés, é um critério que exclui da normalidade da função vertebral aproximadamente 50% dos adolescentes. Assim, o critério para tomada de decisão quanto ao encaminhamento do adolescente para recuperação de maiores índices de flexibilidade precisa ser revisto.
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Pós-graduação em Agronomia (Energia na Agricultura) - FCA
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Pós-graduação em Agronomia (Energia na Agricultura) - FCA
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Pós-graduação em Agronomia (Irrigação e Drenagem) - FCA