910 resultados para forest of trees
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The palm Euterpe edulis is one of the most exploited due the intense illegal extraction, which is very harmful because this species dies right after the cutting process. This study aimed to assess the palms' development as an enrichment plant in a forest fragment belonging to a Preservation Area and the Biosphere Reserve of the Green Belt of Sao Paulo State, in Embu das Artes city. The seeds were obtained from the Instituto Florestal, which follows all the regulations for seeds, in order to get seedlings with a high genetic variation. The seedlings were planted in two successional stages: secondary forest with low trees (SFLT) and secondary forest with medium trees (SFMT). The seedlings survival and growth were periodically assessed and the results were compared by the variance analysis. Both areas presented high rates of survival, which were superior comparing to other similar studies with Euterpe edulis. Despite the successional difference between the areas, the development of the seedlings did not show significant difference on the analysis of variance regarding leaf number, height growth, stem diameter and survival, except for plant height at 60 days after planting, when seedlings planted in SFLT reached higher height (21.38 cm) than when planted in SFMT (19.31 cm).
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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The rationalization of forest harvesting and minimization costs is a constant search by the managers involved in this process, making them decide practices which are economically viable to optimize that operation. This study aimed to evaluate technically and economically the performance of feller-buncher and the forest processor in stands of eucalypts in first cut. The technique analysis included time and movements, productivity, efficiency operational and mechanical availability. The economic analysis included the parameters operational cost, harvesting cost and energy consumption. Aiming the optimization the cost of forest harvesting, the system composed by feller-buncher and processor forest presented itself as a technically and economically viable alternative to harvesting eucalypt in first cut or stands that do not have bifurcated trees.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Despite the Amazon Forest being the largest tropical forest in the world, and cradle of rubber trees (Hevea brasiliensis), no studies have aimed to report the occurrence of mites associated with native trees from this ecosystem. Our survey investigates the phytoseiid mites associated with five species of native rubber trees from nine sites of the Amazon Forest, and also presents a major review of phytoseiid species from natural vegetation in Brazil. We found a total of 1305 mites, belonging to 30 species, of which seven were new to science, Amblydromalus akiri sp. nov., Amblyseius chicomendesi sp. nov., Amblyseius duckei sp. nov., Amblyseius manauara sp. nov., Iphiseiodes katukina sp. nov., Iphiseiodes raucuara sp. nov. and Typhlodromips igapo sp. nov.; beyond two new records for Brazil, Iphiseiodes kamahorae and Amblyseius martus. Our results emphasize the importance of Amazon native trees as an unexplored source of predator mites, which in turn may be further studied as biological control agents of pest mites on rubber trees. The impressive diversity, endemism and rate of new species found highlight the importance of studies on arthropod communities associated with the Amazon vegetation.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Exotic species are used to trigger facilitation in restoration plantings, but this positive effect may not be permanent and these species may have negative effects later on. Since such species can provide a marketable product (firewood), their harvest may represent an advantageous strategy to achieve both ecological and economic benefits. In this study, we looked at the effect of removal of a non-native tree species (Mimosa caesalpiniifolia) on the understory of a semideciduous forest undergoing restoration. We assessed two 14-year-old plantation systems (modified taungya agroforestry system; and mixed plantation using commercial timber and firewood tree species) established at two sites with contrasting soil properties in São Paulo state, Brazil. The experimental design included randomized blocks with split plots. The natural regeneration of woody species (height ≥0.2 m) was compared between managed (all M. caesalpiniifolia trees removed) and unmanaged plots during the first year after the intervention. The removal of M. caesalpiniifolia increased species diversity but decreased stand basal area. Nevertheless, the basal area loss was recovered after 1 year. The management treatment affected tree species regeneration differently between species groups. The results of this study suggest that removal of M. caesalpiniifolia benefited the understory and possibly accelerated the succession process. Further monitoring studies are needed to evaluate the longer term effects on stand structure and composition. The lack of negative effects of tree removal on the natural regeneration indicates that such interventions can be recommended, especially considering the expectations of economic revenues from tree harvesting in restoration plantings.
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We assessed the efficacy of three different forest intervention techniques, in terms of phytosociological and edaphic responses, that were implemented in 2007. In a farm where trees are planted and managed for cellulose production as well as set aside for environmental conservation, four stands were analysed: three of them were considered degraded and were managed using different intervention techniques (transposition, perch, and abandonment), and a fourth stand comprising pristine vegetation was considered a control (reference). Floristic and phytosociology data were collected in three 10 × 10 m plots established in each stand. Also, a total of 48 soil samples were collected to analyse physical and chemical attributes of the topsoil for the different stands. In terms of biodiversity, all the treatments showed significantly lower values when compared to the reference area. However, the soils in all the treatment and reference stands are similar in terms of physical and chemical attributes. Taking into account the specificities of each restoration technique, we verified that the integrated use of a set of management practices, constituted by the (1) abandonment of the area and (2) following a selective killing of the eucalyptus, is the most suitable and promising model to provide fast and effective restoration in terms of environmental indicators.
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This register lists the largest trees of over 80 species identified in Nebraska. The name of the owner and nominator, size and location of each tree follow each listing. Many people across Nebraska have worked hard to make this register as comprehensive and accurate as possible, but the quest to find the largest trees in Nebraska is never over. Champion trees are by nature old, and old trees diminish and die. Larger trees are newly discovered. Thus, this list continually changes as new nominations are submitted.
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Chaetomys subspinosus is the sole species within the Chaetomyinae subfamily of Caviomorph rodents. This poorly studied porcupine is restricted to the Atlantic Forest in eastern Brazil, where deforestation and habitat fragmentation threaten its survival. Data on the ranging and roosting behavior of C. subspinosus is fairly scarce as it is difficult to observe these behaviors in nature and, consequently, it is very rarely detected during field surveys. We monitored the home ranges of three radio-tagged females over the course of 1 year (2005-2006) and collected data on several aspects of their natural history including movement patterns and the use of diurnal roosts and latrines. The animals were monitored at Parque Estadual Paulo Cesar Vinha, a nature reserve dominated by restinga forests, a subtype of Atlantic Forest occurring on sandy soil. The estimated home range varied little between individuals and was relatively small (mean = 2.14 ha/individual and 1.09 ha/individual using minimum convex polygon and kernel methods, respectively). The animals travelled an average of 147 m/night (range: 21-324 m/night) between two consecutive day roosts. The day roosts were mostly located on vine and liana tangles in the canopy which also aid in connecting the canopy to adjacent trees or the forest floor. Latrines were mostly located near the ground in places heavily protected by spiny bromeliads or by other tangled vegetation. Our data suggests that C. subspinosus has the smallest range among all Neotropical Erethizontids which is likely due to its small size and strictly folivorous diet. Our data also helps explain why C. subspinosus is so difficult to observe in nature: researchers should focus on arboreal masses of tangled vegetation where individuals will normally rest during the day. (C) 2011 Deutsche Gesellschaft fur Saugetierkunde. Published by Elsevier GmbH. All rights reserved.
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Investigating tree's spatial patterns according to their size classes and according to their more abundant species can provide evidences about the structure of the vegetal community, since the spatial pattern is a key question for forestry ecology studies. The tree spatial organization patterns on the environment depend on several ecological processes and on the specific characteristics of each environment, so that the best understanding of this frame provides important elements for the knowledge on forestry formation. This paper aimed to study tree spatial patterns, according to the diameter classes and from four most abundant species in different forests, in order to provide evidences regarding to the ecology of each vegetal community. The spatial pattern description in each forestry formation was developed using Ripley's K function. The studied forestry formations were: Ombrophilous Forest, Cerradao, Seasonal Forest and Restinga Forest. In this work, a 10.24 ha plot was installed in each forestry formation, and every tree, with a circumference at breast height (CBH) larger than 15 cm were measured, georeferenced and identified. The obtained data highlights the aggregated character in tropical forests, as observed in every studied forest. The 'Cerraddo' and 'Restinga' forest trees showed close aggregate patterns. In the Ombrophilous forest, for all distance scales, the aggregate pattern was meaningful. In the seasonal forest, a random tendency was observed, although a meaningful aggregation was observed in all short distances. The spatial pattern by diameter classes was generally aggregated for trees smaller than 10 cm of diameter and between 10 and 20 cm and random for the others, proving the existence of a tendency which in young trees is more aggregated than in old ones. The spatial pattern of the dominant species is always strongly similar to the general pattern of each forestry formation. The differences between the spatial patterns of two or three coincident species, among the forestry formations, indicate that its pattern is influenced by each different environment. This stands out the importance of its self-ecology and of its ecological processes, intrinsic of each community that can explain the observed patterns.
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Metrodorea nigra (Rutaceae) is an endemic Brazilian tree of great ecological importance, frequently found in the submontane regions of ombrophilous dense and semideciduous forests. This tree is useful for reforesting degraded areas and the wood can be employed in construction. We developed 12 microsatellite markers from a genomic library enriched for GA/CA repeats, for this species. Polymorphisms were assessed in 40 trees of a highly fragmented population found in Cravinhos, State of Sao Paulo, in southeastern Brazil. Among the 12 loci, 8 were polymorphic and only one had fixed alleles in this population. The number of alleles per locus and expected heterozygosity ranged from 2 to 11 and from 0.190 to 0.889, respectively. These results revealed moderate levels of genetic variation in M. nigra population when compared to other tropical species. Additionally, transferability of the 12 primers was tested in seven other Brazilian Rutaceae tree species (endemics: M. stipularis, Galipea jasminiflora, Esenbeckia leiocarpa and non-endemics: E. febrifuga, E. grandiflora, Balfourodendron riedelianum, Zanthoxylum riedelianum). Transferability ranged among species, but at least 8 loci (similar to 67%) amplified in M. stipularis, demonstrating a high potential for transferring microsatellite markers between species of the same genus in the Rutaceae family.
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Productive and reproductive traits of beehives are influenced by climate and food availability in the region where the bees are reared or maintained, thus honey and pollen storage, egg-laying conditions of the queen as well as comb occupation are subject to seasonal variations. The present study was conducted in the apiary of the Department of Entomology and Acarology, College of Agriculture Luiz de Queiroz, ESALQ/USP, in the municipality of Piracicaba, in an area containing fruit trees, ornamental plants and a fragment of a native forest. The objective was to identify protein sources used by honeybees (Apis mellifera) over a whole year (2010-2011) in remnants of the Atlantic forest, information that can be used in the conservation and restoration of degraded areas. For sample preparation, the acetolysis method was adopted (Eredtman 1952) and the quantitative analysis was performed by counting successive samples of 900 grains per sample which were grouped by botanical species and/or pollen types. The results show that the bees used various plant types in the area, including ruderal species, to maintain their colonies. Apis mellifera seeks food sources in all plants in the surroundings of the apiary, including herbaceous, shrubs, trees, native or introduced. Eucalyptus sp. played an important role as a food source in all seasons due to its wide availability around the apiary and its high flower production. The most frequent pollen types (greater than 10% of the sample) were Anadenanthera sp., Acacia sp, Miconia sp. and Eucalyptus sp. in winter; Philodendron sp., Mikania cordifolia, Parthenium and Eucalyptus sp. in spring; Alternanthera ficoidea, Chamissoa altissima and Eucalyptus sp. in summer; Philodendron sp., Raphanus sp. and Eucalyptus sp. in autumn.
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The aim of this study was to estimate the stock of biomass and organic carbon in a montane mixed shade forest located near General Carneiro, PR. 20 plots of 12 m x 12 m were installed, in which all trees with a CBH (Circumference at Breast Height) >= 31.4 cm were felled. From these the following information was obtained: total height, commercial height (agreed as being the morphological inversion point in the natural forest and the height of the first live branch), CBH, identification and collection of herbarium specimens. For the quantification of biomass in the understory and roots, three subunits 1 m x 1 m in each sampling unit were installed (12 m x 12 m) arranged in the lower left corner, center and diagonal upper right corner. To quantify accumulated litter at random, eight samples in each sampling unit were collected (12 m x 12 m), using a metal device measuring 0.25 m x 0.25 m. The montane mixed shade forest has more than 85% of its total biomass and total organic carbon stored in above ground plant structures. The total stock of organic carbon found in this study (104.7 Mg ha(-1)) demonstrates the importance of maintaining and preserving natural ecosystems as a way of maintaining this stock of organic carbon fixed in plant biomass.