255 resultados para Forest reserves.


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The objective of this work was to evaluate the use of a low-cost trap to capture Cerambycidae in different seasons in planted forests in Brazil. Thirty polyethylene-terephthalate trap bottles per hectare were used, disposed at every 50 m. The traps were red painted and contained glass flasks with a mixture of ethanol, methanol and benzaldehyde. There were soap and water at the trap bottom. The traps were checked biweekly for beetle presence. Sampling time required one minute per sample, and traps were easy to use. Total sampling cost, including materials and labor, was US$ 13.46 per sample. Six Cerambycidae species were captured along the dry and rainy seasons.

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The objective of this work was to evaluate the distribution pattern and composition of soil organic matter (SOM) and its physical pools of Leptosols periodically affected by fire over the last 100 years in South Brazil. Soil samples at 0-5, 5-10, and 10-15 cm depths were collected from the following environments: native pasture without burning in the last year and grazed with 0.5 livestock per hectare per year (1NB); native pasture without burning in the last 23 years and grazed with 2.0 livestock per hectare per year (23NB); and an Araucaria forest (AF). Physical fractionation was performed with the 0-5 and 5-10 cm soil layers. Soil C and N stocks were determined in the three depths and in the physical pools, and organic matter was characterized by infrared spectroscopy and thermogravimetry. The largest C stocks in all depths and physical pools were found under the AF. The 23NB environment showed the lowest soil C and N stocks at the 5-15 cm depth, which was related to the end of burning and to the higher grazing intensity. The SOM of the occluded light fraction showed a greater chemical recalcitrance in 1NB than in 23NB. Annual pasture burning does not affect soil C stocks up to 15 cm of depth.

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The objective of this work was to estimate the mating system parameters of a andiroba (Carapa guianensis) population using microsatellite markers and the mixed and correlated mating models. Twelve open‑pollinated progeny arrays of 15 individuals were sampled in an area with C. guianensis estimated density of 25.7 trees per hectare. Overall, the species has a mixed reproductive system, with a predominance of outcrossing. The multilocus outcrossing rate (t m = 0.862) was significantly lower than the unity, indicating that self‑pollination occurred. The rate of biparental inbreeding was substantial (t m ‑ t s = 0.134) and significantly different from zero. The correlation of selfing within progenies was high (r s = 0.635), indicating variation in the individual outcrossing rate. Consistent with this result, the estimate of the individual outcrossing rate ranged from 0.598 to 0.978. The multilocus correlation of paternity was low (r p(m) = 0.081), but significantly different from zero, suggesting that the progenies contain full‑sibs. The coancestry within progenies (Θ = 0.185) was higher and the variance effective size (Ne(v) = 2.7) was lower than expected for true half‑sib progenies (Θ = 0.125; Ne(v) = 4). These results suggest that, in order to maintain a minimum effective size of 150 individuals for breeding, genetic conservation, and environmental reforestation programs, seeds from at least 56 trees must be collected.

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The essential oils from leaves of four Cryptocarya spp endemic in the Brazilian Atlantic rain forest were obtained by hydrodistillation and shown by GC-MS analysis to contain mono and sesquiterpenes. The major components of the oil of Cryptocarya moschata were linalool (34.3%), a-terpinene (17.0%), g-terpinene (10.4%), 1,8-cineole (5.8%) and trans-ocimene (4.8%), whilst those of C. botelhensis were a-pinene (22.7%), b-pinene (9.2%), trans-verbenol (8.4%), trans-pinocarveol (5.5%) and myrtenal (5.4%). The principal compounds of C. mandioccana oil were b-caryophyllene (13.8%), spathulenol (10.2%), caryophyllene oxide (7.8%), d-cadinene (6.9%) and bicyclogermacrene (6.4%), whilst those of C. saligna were germacrene D (15.5%), bicyclogermacrene (13.8%), spathulenol (11.8%) and germacrene B (5.7%).

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We studied the adsorption of glyphosate (GPS) onto soil mineral particles, using FT-IR and Mössbauer spectroscopy. From IR measurements for samples collected under native vegetation of a forest reserve, bands at 1632 and 1407 cm-1 could be attributed to the interaction between the carboxylic group of GPS and structural Al3+ and Fe3+ on the surface of mineral particles; bands at 1075 and 1000 cm-1 were observed only for cultivated soil. Mössbauer spectra for these soils were definitely fitted using a broad central doublet in addition to the magnetic component. This multiple quadrupolar component may be attributed to all non-magnetic Fe3+ contributions, including that of the GPS/Fe3+ complex.

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This study investigated the regeneration variation of five commercially valuable tree species in relation to different intensities of felling in fourteen 4-ha plots in an area under experimental forest management. This experiment was carried out in a typical Amazonian tropical forest sample on "terra-firme," in Manaus (AM). Plots were logged 7 and 8 years (1987 and 1988), or 3 years (1993) before the study. All trees with height greater than 2 m, and diameter at breast height (DBH) smaller than 10 cm were measured. Only Aniba hostmanniana, Ocotea aciphylla, Licaria pachycarpa, Eschweilera coriacea and Goupia glabra were sufficiently common for individual analyses. These species have high timber values in the local market. Eight years after logging, the species responded differently to logging intensities. The numbers of individuals of Goupia glabra and Aniba hostmanniana were positively related to the intensity of logging, while Ocotea aciphylla, Licaria pachycarpa, and Eschweilera coriacea showed no statistically significant response. In the most recently (1993) logged areas, Goupia glabra and Aniba hostmanniana had higher numbers of individuals than the control plots.

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The characterization of different ecological groups in a forest formation/succession is unclear. To better define the different successional classes, we have to consider ecophysiological aspects, such as the capacity to use or dissipate the light energy available. The main objective of this work was to assess the chlorophyll fluorescence emission of tropical tree species growing in a gap of a semi-deciduous forest. Three species of different ecological groups were selected: Croton floribundus Spreng. (pioneer, P), Astronium graveolens Jacq. (early secondary, Si), and Esenbeckia febrifuga A. Juss. (late secondary, St). The potential (Fv/Fm) and effective (deltaF/Fm') quantum efficiency of photosystem II, apparent electron transport rate (ETR), non-photochemical (qN) and photochemical (qP) quenching of fluorescence were evaluated, using a modulated fluorometer, between 7:30 and 11:00 h. Values of Fv/Fm remained constant in St, decreasing in P and Si after 9:30 h, indicating the occurrence of photoinhibition. Concerning the measurements taken under light conditions (deltaF/Fm', ETR, qP and qN), P and Si showed better photochemical performance, i.e., values of deltaF/Fm', ETR and qP were higher than St when light intensity was increased. Values of qN indicated that P and Si had an increasing tendency of dissipating the excess of energy absorbed by the leaf, whereas the opposite was found for St. The principal component analysis (PCA), considering all evaluated parameters, showed a clear distinction between St, P and Si, with P and Si being closer. The PCA results suggest that chlorophyll fluorescence may be a potential tool to differentiate tree species from distinct successional groups.

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Termites are well -known for their capacity to damage and destroy wood and wood products of all kinds in the tropics and subtropics. A field test was undertaken to evaluate variations in wood consumption of Pinus sp. and three species of Eucalyptus by subterranean termites. The test consisted of wooden stakes of each species being initially submitted to water immersion for 0, 24, 48 and 72 h, and buried in the ground to natural infestation by subterranean termites for an exposure period of 30, 45 and 60 days. Three species of subterranean termites were identified: Heterotermes longiceps (Snyder), Coptotermes gestroi (Wasmann) (Isoptera: Rhinotermitidae), and Nasutitermes jaraguae (Holmgren) (Isoptera: Termitidae). This is the first record of occurrence of H. longiceps in the state of Rio de Janeiro. Although the wood-consumption rates were not correlated significantly with their wood densities, there was a tendency of the softwoods (E. robusta and Pinus sp.) to be more consumed by subterranean termites than the woods of intermediate hardness (E. pellita and E. urophylla). Among the eucalyptus, E. robusta showed to be more susceptible to attack by subterranean termites than E. pellita and E. urophylla

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Young nests of Acromyrmex subterraneus brunneus are characterized by refuse soil in the exterior of the nest, a single fungus chamber 11 to 20 cm deep in relation to soil surface and internal volume ranging from 0.3 to 1.5 liters. These nidification patterns are important characteristics for identifying and understanding the interactions between species and their habitats.

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The objective of the present study was to evaluate the effects of industrial solid waste (whitewash mud) on geotechnical properties considering the following engineering parameters: California Bearing Ratio (CBR), Atterberg limits and Permeability test. Seven soil samples derived from Alagoinhas, Bahia - Brazil, were classified by the Transportation Research Board (TRB) system. Two were selected as having a great geotecnical potential classified as A-3 (0) and A-2-4 (0), whitewash mud contents 10%, 15%, 20% and 25% dry weight and medium compaction effort were studied in the laboratory testing program. The results indicated the soil denominated good gravel as being the most promising one, when stabilized with whitewash mud, reaching the best results with the dosage of 20 and 25% of whitewash mud.

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The objective of this study was to investigate reserve mobilization in Caesalpinia peltophoroides seeds during germination and initial seedling growth. The variation in these compounds was analyzed from the pre-germination period (0 to 5 days after sowing - DAS) to the total cotyledon senescence and abscission at 35 DAS. For this histochemical tests were made on cotyledons fixed in FAA50 or included in glycol-metacrylate. To follow the mobilization of the main reserve compounds, sudan III was used to detect total lipids, xylidine Ponceau to detect total proteins, lugol to detect starch and polarized light to visualize the crystals. The lipids, present in a great quantity in the cotyledon, gradually decreased in the period studied. A greater quantity of starch was observed on the 10th DAS than in the previous periods and it was totally consumed by 30 DAS. The distribution pattern and the morphology of the protein material were very modified by 10 DAS, a period during which it was intensely consumed, remaining only parietally fragments distributed, that practically disappeared at 25 DAS. The calcium oxalate druses were not consumed during the period studied, there was only crystal agglutination.

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Silvicultural and ecological knowledge about tree species is basic to restoration planning, particularly in high diversity regions. Here we present a comparison of four native tree species from the middle Uruguay River basin, Brazil-Argentine frontier: Heliocarpus americanus L. (Malvaceae), Maclura tinctoria (L.) D. Don ex Steud. (Moraceae), Schinus terebinthifolius Raddi (Anacardiaceae) and Cordia trichotoma (Vell.) Arrab. ex Steud. (Boraginaceae). We obtained data on initial growth, light interception, litterfall and litter mineral contents. H. americanus presented the greatest height and the lowest value of height/crown width ratio. H. americanus and M. tinctoria presented the highest light interception rate (>94 %) and highest litterfall (879 ± 151 and 792 ± 164 g·m-2·year-1, respectively). For the set of species, the lowest litterfall occurred between July and September. H. americanus presented the highest K concentration (1.13%) in the litter, while C. trichotoma had the highest values of Ca and Mg (6.35 and 2.02 %, respectively). S. terebinthifolius had the lowest light interception rate and litter mineral content.

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The analysis of species composition and its effects on sustainability restoration processes in the Atlantic Forest with poor environmental attributes is important to improve rehabilitation techniques for disturbed ecosystems. Reforestation projects were used as Biological Measures (BM) of rehabilitation, where treatments differ in the composition of exotic species, utilized as anthropic pioneers: BM1 - 82% (73% Mimosa caesalpiniifolia Benth, 9% Eucalyptus citriodora Hook.); BM2 - 91% (9%, 82%); and BM3 - 25% (15%, 10%). The monitoring of spontaneous regeneration was evaluated in three 12-year-old reforestation sites between thr rainy season of 2004 and 2005, and compared with an approximately 100-year-old native forest fragment and a grassland: ecosystems with inertial tendency toward recuperation and degradation, respectively. It was detected that exotic species used as anthropic pioneers strongly influenced regeneration: BM1 (75%), BM2 (85%), BM3 (55%), Forest (0%) and Grassland (50%). The highest similarity of species with forest regeneration (5%) was found for treatment BM3.

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Termites are well known for their ability to damage wood and various types of wood-derived products. This study was performed in the municipality of Seropédica, Rio de Janeiro state, Brazil, with the objective of evaluating the susceptibility of the wood of five different forest species to the activity of the Asian subterranean termite, Coptotermes gestroi. Wood stakes from the following forest species were used as specimens: pine (Pinus sp., Pinaceae), Brazil nut (Bertholletia excelsa, Lecythidaceae), cabbage angelin (Andira inermis, Leguminosae-Papilionoideae), maçaranduba (Manilkara huberi, Sapotaceae) and pink ipê (Tabebuia avellanedae, Bignoniaceae). The stakes, with dimensions of 2 cm x 2 cm x 16 cm, were subjected to the activity of C. gestroi from September 2, 2006 to June 2, 2007. The experimental design consisted of randomized blocks with four replications in an 11 x 5 x 3 factorial arrangement. Twelve stakes of each of the five forest species were installed at each of eleven sites, totaling 660 stakes. Three evaluations were performed, at 90, 180 and 270 days after stake installation. The results indicated that the pine, Brazil nut and cabbage angelin stakes were more susceptible to C. gestroi attack, while the pink ipê and maçaranduba stakes suffered no significant damage from this termite. There was a significant negative correlation between the wood consumption rate and the wood density of the species studied. The woods most susceptible to C. gestroi attack presented moderate to low densities and therefore less resistance, as in the case of pine and cabbage angelin.

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Approximately 7.2% of the Atlantic rainforest remains in Brazil, with only 16% of this forest remaining in the State of Rio de Janeiro, all of it distributed in fragments. This forest fragmentation can produce biotic and abiotic differences between edges and the fragment interior. In this study, we compared the structure and richness of tree communities in three habitats - an anthropogenic edge (AE), a natural edge (NE) and the fragment interior (FI) - of a fragment of Atlantic forest in the State of Rio de Janeiro, Brazil (22°50'S and 42°28'W). One thousand and seventy-six trees with a diameter at breast height > 4.8 cm, belonging to 132 morphospecies and 39 families, were sampled in a total study area of 0.75 ha. NE had the greatest basal area and the trees in this habitat had the greatest diameter:height allometric coefficient, whereas AE had a lower richness and greater variation in the height of the first tree branch. Tree density, diameter, height and the proportion of standing dead trees did not differ among the habitats. There was marked heterogeneity among replicates within each habitat. These results indicate that the forest interior and the fragment edges (natural or anthropogenic) do not differ markedly considering the studied parameters. Other factors, such as the age from the edge, type of matrix and proximity of gaps, may play a more important role in plant community structure than the proximity from edges.