da Silva M.L.M.B.,Federal University of Vales do Jequitinhonha and Mucuri |
Binoti D.H.B.,Federal University of Viçosa |
Leite H.G.,Federal University of Viçosa |
Garcia S.L.R.,Instituto Vicosence Of Ensino E Pesquisa |
da Silva A.A.L.,Engenheiro Florestal
Revista Arvore | Year: 2013
The objective of this study was to investigate the application of the Birnbaum-Saunders function with three and two parameters and using the minimum diameter as parameter for describing the location diameter structure of eucalypt stands, and propose a model for diameter distribution using the function. The function was fitted to data from the inventory of permanent plots, measured at six ages. The adhesion function of the data was confirmed by Kolmogorov-Smirnov test. The diameter distribution models proposed showed acceptable values of correlation coefficient. The graphic analysis of residues showed no bias for function of two parameters and γ = dapmin. The function with two parameters and γ = dapmin can be used to describe the diameter distribution of eucalypt plantations.
Paula R.R.,University of Sao Paulo |
Pereira M.G.,Federal Rural University of Rio de Janeiro |
Santiago R.R.,Engenheiro Florestal |
Amorim H.B.,Federal Rural University of Rio de Janeiro
Floresta e Ambiente | Year: 2012
The purpose of this study was to evaluate the influence of soil properties in the development of eucalyptus plantation. Four-year old stands of Eucalyptus urophylla S. T. BLAKE were evaluated in 'Mario Xavier' National Forest (FLONA) in topographic sequence: two Ultisol areas located in the shoulder (Upper Third) and back slope (Medium Third), and a Planossol area located in the foot slope (Lower Third). For each soil area, a study portion was established and the silvicultural aspects of the stands were evaluated; soil samples were also collected for fertility and bulk density assessment. No significant differences were observed in the chemical properties of the soil, but there were significant differences in bulk density, though, especially in the back slope (MT). Although trees presented longer survival in the foot slope (LT), it was observed that the diameter distribution was more symmetric, with trees of larger diameter and greater basal area per hectare in the shoulder (UT) and back slope (MT). Results obtained suggest the need for differential management of eucalyptus stands due to marked relief differences, once they can influence the age of harvest and final use of wood.
Effects of the reduced impact logging on natural regeneration in a terra firme dense forest in the municipality of Paragominas in Brazilian Amazonia [Efeito da exploração florestal de impacto reduzido sobre a regeneração natural em uma floresta densa de terra firme no município de Paragominas na Amazônia brasileira]
Hirai E.H.,Engenheira Ambiental |
De Carvalho C.J.R.,Pesquisador Embrapa Amazonia Oriental |
Silva J.N.M.,Engenheiro Florestal |
De Carvalho J.O.P.,Federal Rural University of Amazonia |
De Queiroz W.T.,Federal Rural University of Amazonia
Scientia Forestalis/Forest Sciences | Year: 2012
The motivation for this study was the scarcity of information on ecological sustainability of natural forests in areas affected by logging. The objective was to find out if there is any difference in regeneration between the unlogged area and the logged area; regeneration among years after logging; and to evaluate the capacity of the natural regeneration on recovery of the floristic composition and structure of the logged forest. Natural regeneration was evaluated in three areas in different occasions (2000, 2003 and 2006) over a seven-year period at Rio Capim forest management unit, in the municipality of Paragominas, Pará state. Data were collected in gaps, primary and secondary skid trials, and log decks and in the remaining forest, considering individuals from 2.5 cm to 10.0 cm diameter. Richness, abundance, diversity, evenness and floristic similarity were evaluated. Changes occurred in the floristic composition and abundance of individuals in DBH 2.5-10.0 cm, in the seven-year study period, mainly in the primary skid trials and log decks. In the remaining forest, dynamics of species and individuals was higher for shade-tolerant species, but in gaps, skid trials and log decks pioneer species were dominant. In the log decks and skid trails the abundance of individuals with DBH greater than 2.5 cm was very low. Natural regeneration in areas opened by logging showed only a few timber species with commercial value being influenced by the remaining forest. Therefore, one can suggest that seedlings (DBH < 2.5 cm) of natural regeneration of commercial species must be assisted by post-harvesting silviculture; and seedlings produced in nurseries must be planted in gaps to guarantee a reasonable stock of commercial timber species for future harvests.
Alvarenga L.H.V.,Engenheiro Florestal |
Marcio de Mello J.,Federal University of Lavras |
Carolina de Lima Guedes I.,Engenheira Florestal |
Roberto Soares Scolforo J.,Federal University of Lavras
Cerne | Year: 2012
This study verified the existence of spatial dependence in a Brazilian savanna fragment and incorporated it to the forest inventory by stratifying, compared the accuracy of systematic sampling (SS) with stratified random sampling (SRS) and verified the accuracy of SRS with reduced sampling intensity. A total of 157 sample plots (area of 1000 m2) were allocated and distributed systematically in the area. The circumference at 1.3m from the soil and the total height of all trees were measured in the plots. The volume of each plot was obtained by volume equations generated for the physiognomy. It was found that the dendrometric characteristic of volume is spatially structured. The inventory error obtained for the SS was 11.38% and 6,47% for SRS. With the sampling intensity decreased by 60%, the error for SRS was 9.93%. These results showed that even with a marked reduction in the sampling intensity, the estimates by stratified random sampling (SRS) is more accurate than the estimates of systematic sampling (SS). Therefore, the stratification based on the spatial dependence in the characteristic of interest is a very useful tool in improving the quality of forest inventory estimators even with a reduction in sampling intensity.
Viera M.,Federal University of Santa Maria |
Schumacher M.V.,Federal University of Santa Maria |
Liberalesso E.,Engenheiro Florestal |
Caldeira M.V.W.,Federal University of Espirito Santo |
Watzlawick L.F.,State University of the Central West
Floresta e Ambiente | Year: 2013
In this paper, we aimed to review the main benefits of the mixed plantation of eucalyptus with nitrogen-fixing legume trees. To this end, the ecological interactions of the species involved in the system was analyzed, as well as the space architecture used and the possible increase in productivity caused by the intercropping. On this basis, it was possible to observe that the mixed cropping of eucalyptus with nitrogen-fixing legume trees should be implemented only in locations where the processes and interactions between species will increase the growth, biomass production or quality of desired product. In general, studies indicate that mixed plantation provides an increase in productivity in eucalyptus stand. However, it is important to analyze the interactions of mixed stand until the age of rotation, so that the possible effects of atmospheric nitrogen fixation by legume trees on the productivity of eucalyptus can be verified.
de Oliveira Freire A.L.,Federal University of Campina Grande |
de Sousa Filho G.M.,Engenheiro Florestal |
de Miranda J.R.P.,Federal University of Campina Grande |
Souto P.C.,Federal University of Campina Grande |
de Araujo L.V.C.,Federal University of Campina Grande
Ciencia Florestal | Year: 2010
The objective of this study was to verify the effects of soil salinity on growth and nutrient and sodium accumulation in neem (Azadirachta indica) and cinnamomum (Melia azedarach). The experimental delineation was completely randomized in a 2 × 4 factorial arrangement, with two species (neem and cinnamomum), four salinity levels (electrical conductivity 0.49 (non saline soil), 4.15, 6.33 and 10.45 dS m -1) and four replications. Initially, plants were grown in tubes, and 60 days after emergence, they were transferred to pots containing 3 kg of substrate [soil + manure (2:1)], according to the saline treatment. After 45 days, plant height, dry matter (leaves, stem, shoot (stem + leaves), roots and total) and N, P, K, Ca, Mg, S and Na + shoot accumulation were evaluated. Salinity reduced the plant height in both species, but the effect was more pronounced in neem. Increases in soil salinity caused an increase in the accumulation of Na + and reduced the accumulation of nutrients in shoots of both species, especially in neem. The cinnamomum was more tolerant to salinity levels of soils than neem.
Alonso J.M.,Federal Rural University of Rio de Janeiro |
Dos Santos Leles P.S.,Federal Rural University of Rio de Janeiro |
Do Nascimento Ferreira L.,Engenheiro Florestal |
Da Silva Araujo Oliveira N.,Engenheiro Florestal
Ciencia Florestal | Year: 2015
This study aimed to evaluate the deposition of litter, during one year period, in forest restoration plantation, deployed at different spacings. The planting took place in November 2004, at the Thermoelectric Plant ‘Barbosa Lima Sobrinho’, in Seropédica, Rio de Janeiro state. In December 2007, nine circular collectors were installed, tied to trees with nylon, in the four studied spacings: 1 x 1 m; 1.5 x 1.5 m; 2 x 2 m; and 3 x 2 m. The collections were done monthly, until December 2008. The material was taken to the laboratory, separated into leaves, branches, reproductive and miscellaneous and after being dried in stove at 65 °C for 48 hours, it was weighed. The values found for the total deposition of litter were, from the more to the less dense spacing: 6.93; 4.48; 5.12; and 3.71 Mg ha-1. The spacing which produced a greater quantity of litter was the 1 x 1 m. The litter deposition was higher in the dry season. The seasonal pattern was similar in the different spacings. The leaf fraction was predominant in all the spacings. The litter deposition, in general, was positively correlated with canopy cover index and was not correlated with the basal area of the stand. The obtained values of the litter production in this study can be considered similar to those found in secondary forest near the study area. © 2015, Universidade Federal de Santa Maria. All rights reserved.
Lira J.M.S.,Federal University of Lavras |
Ferreira R.A.,Federal University of Sergipe |
Junior C.D.S.,Federal University of Sergipe |
Neto E.M.d.S.,Engenheiro Florestal |
Santana W.S.,Federal University of Sergipe
Ciencia Florestal | Year: 2013
In order to select species for using in the restoration of riparian forests on the banks of the Sao Francisco River, in the state of Sergipe, an experiment was conducted to evaluate the growth and gas exchange of plants Lonchocarpus sericeus (Poir.) D.C., subject to flooding conditions in the nursery. The experiment was conducted at Forest Nursery, Department of Forest Sciences, Federal University of Sergipe (UFS), the municipality of São Cristóvão, (11 ° 01 'S latitude and 37 ° 12' longitude W, altitude 20 m), state of Sergipe, Brazil, from October 2006 to January 2007 under ambient conditions. We used a completely randomized design (CRD), factorial (2x7), two treatments (control - T0, plants at field capacity and flooded - T1) and days after flooding (0, 15, 30, 45, 60, 75 and 90 days). To simulate the condition of flooding, the plants were placed in plastic pots of black color with a volume of 5 L and more substrate. Following these pots were attached to pots with a volume of 10 L, which was added water until it reaches a water depth of 5 cm above the top of the plants. The control plants kept in pots with a volume of 5 L substrate maintained at field capacity. In non-destructive variables were used four replicates per treatment evaluated every fifteen days, where each replicate consists of six plants, totaling 24. Destructive variables used were 4 replicates per treatment, determined biweekly from 15 days after flooding, where each replicate consists of a plant totaling 24 plants. Therefore, 48 plants were used per treatment. The non-destructive variables were height, diameter and number of leaves. While the destructive variables analyzed were dry weight of roots, dry weight of shoots and dry weight of root / shoot ratio. In addition, we carried out analysis of gas exchange on a monthly basis and evaluated twelve plants per treatment, with two sampling leaves, fully expanded, per plant. The biometric variables were subjected to analysis of variance and subsequently the average test (Tukey p <0.05), while the values of gas exchange were taken from the standard deviations of the mean. Thus, we observe that the flooding caused a reduction in height and dry mass of root / shoot ratio, from 30 days after treatment application. In addition, flooded plants showed morphological changes such as hypertrophy of adventitious roots and lenticels, characteristics of species tolerant to flooding. The net photosynthetic rate has been reduced by 48.20% compared to control after 60 days. However, despite reductions in growth variables and gas exchange species Lonchocarpus sericeus showed promise in the recovery of riparian vegetation, due to its morphological characteristics of species tolerant to flooding.
de Barros D.A.,Federal University of Lavras |
Guimaraes J.C.C.,Federal University of Lavras |
Pereira J.A.A.,Federal University of Lavras |
Borges L.A.C.,Federal University of Lavras |
And 2 more authors.
Revista Escola de Minas | Year: 2012
The intensive use of mineral resources brings along significant changes to the environment. The mining sector is essential for world economics, as long as it is operated on a basis that is technically coherent, socially fair and environmentally correct. This study aimed to characterize the bauxite mining of the Poços de Caldas plateau, MG, investigating its respective socio-environmental impacts. Through the overview presented, one can conclude that in most situations, the bauxite miningat the Poços de Caldas plateau mitigates its negative social and environmental impacts in a satisfactory manner in addition to generating positive social impacts; and the restoration methods of the mining-disturbed ecosystems have been continually improved and should be replicated by small-and-mediumsized companies.
Vatraz S.,Federal Rural University of Amazonia |
De Carvalho J.O.P.,Engenheiro Florestal |
Gomes J.M.,Federal Rural University of Amazonia |
Taffarel M.,Federal Rural University of Amazonia |
Ferreira J.E.R.,CKBV Florestal Ltda.
Scientia Forestalis/Forest Sciences | Year: 2012
The effects of reduced impact logging and silvicultural treatments on the growth rate of Laetia procera (Poepp.) Eichler (pau-jacaré) were evaluated on trees with DBH > 35 cm, in 700 ha of terra firme natural forest in the municipality of Paragominas, PA. Seven treatments were established, in six of which liana cutting and competing tree girdling were applied, and one of them was considered as a control. Annual diameter increment of the species was calculated from 2005 to 2009, considering also crown shape of trees, intensity of light on the crowns and presence or effect of liana on trees. Silvicultural treatments did not promote significant differences on the growth rate after five years (2005-2009) of logging and after four years of liana cutting and tree girdling.