Navegando por Assunto "Dom Eliseu - PA"

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Acesso aberto (Open Access)
Comportamento silvicultural e dinâmica de serapilheira em plantios de duas espécies florestais na Amazônia oriental brasileira
(Universidade Federal do Pará, 2011) SOUSA, Vanesa Gomes de; BRIENZA JÚNIOR, Silvio; http://lattes.cnpq.br/1750852376922258
The deforestation in the Brazilian Amazonia has already altered about 750 million hectares and of this total, 20% are found with some level of degradation. The reincorporation to the productive process of the areas altered with the reforestation of tropical species of commercial value, it is an alternative to minimize the environmental impacts, with ecological benefits, increase of the wood offer and decrease of the pressure on the remaining natural forests. However, one of the great difficulties for the reforestation is the lack of scientific knowledge on the growth of native and exotic species. This work had as objective evaluates the efficiency of different systems of plantings with native and exotic forest species for recovery of altered land. The work was accomplished in Dom Eliseu city, state of the Pará, in three systems of land use: pure planting (Schizolobium parahyba var. amazonicum and Khaya ivorensis), mix of two forests species (S. parahyba var. amazonicum and K. ivorensis) and agroforestry system (S. amazonicum and Musa sp). To The forty months of age, in planting pure, S. parahyba var. amazonicum showed larger growth in height and dbh in the spacing 4 m x 3 m and K. ivorensis in the spacing 4 m x 4 m. However, the S. parahyba var. amazonicum presented better performance in the system mixed planting and agroforest system. The best performance of K. ivorensis was in the mixed system of species. Among the planting systems studied (mix of species and agroforest system), the litterfall was more in the mix of species with 3.737,5 kg ha-1, and the largest contribution of biomass was of the S. parahyba var. amazonicum. The largest biomass reduction was observed in the agroforest systems. Was evidence correlation negative between litterfall and rainfall to S. parahyba var. amazonicum and positive for K. ivorensis. The obtained results showed that the forest model of consortium of species was shown promising and it can be an alternative for recovery of altered areas, in way to offer different wood options and at the same time, to join positive factors in relation to biomass production and physicchemistry aspects of the soil.
Acesso aberto (Open Access)
Equações alométricas para estimar a biomassa acima do solo em floresta plantada com tachi-branco (Tachigali vulgaris), Dom Eliseu/ Pará.
(Universidade Federal do Pará, 2019-07-24) CERVEIRA, Suzane Serrano; CATTANIO, José Henrique; http://lattes.cnpq.br/1518769773387350
The biomass study in tropical FORESTS has played a major role in relation to the contribution of ecosystems to the global carbon cycle. Many articles suggest planting Tachigali vulgaris (Taxi-White) for carbon capture projects in the Amazon and the generation of carbon credits. However little is known how to estimate the biomass increment and how different spacing interferes with the local microclimate. The present study was conducted at Genesis farm in Dom Eliseu city, Pará State, aimed to determine allometric curves for accumulation of aboveground biomass using destructive methods, and the carbon in the biomass and consequent micrometeorological variations in Taxi-White in spacing 4mx2m, 4mx3m and 4mx4m, with population density ranging from 208 to 403 plants per plot. For the equations used a database of 54 trees of a single species, in which were measured variables total height, diameter at breast height (DBH), each sample tree was felled and split the trunk components, branches, and leaves. The fresh weight of each component was obtained in place, and green samples were collected, weighed and brought to the laboratory in Bethlehem to oven drying to constant weight. 17 models of regression equations were used commonly used in the literature, being chosen equations with a higher coefficient of determination (R²). The stock biomass and shoot carbon were observed in the denser spacing, ie, 4mx4m, focusing mainly on the tree trunk. The distribution of the moisture content of classes was: leaves > branches > trunk. The trunk segment is divided according to their height into steps (BASE, DAP, 25%, 50%, 75% and 100% of the total stem height, DAP had a higher moisture content than the other compartments. The temperature was greater spacing with lower density (4mx4m) and the relative humidity had its highest values for spacing with higher densities (4mx2m). The months of September and October showed higher temperature and lower relative humidity, however, the months of November and December, showed lower temperature and higher relative moisture.
Acesso aberto (Open Access)
Estoques e fluxos de carbono em plantações florestais jovens de Acacia mangium e Schizolobium parahyba var. Amazonicum na Amazônia Oriental
(Universidade Federal do Pará, 2010) FREITAS, Jorge Fernando Barros de; VASCONCELOS, Steel Silva; http://lattes.cnpq.br/0719395243841543
Forest plantations are considered as an alternative land use to mitigate the effects of climate change due to their potential for carbon sequestration in tree species. However, there is little information about carbon stocks and fluxes in forest plantations commonly used in the tropics, especially in the Amazon. The aim of this study was to quantify aboveground carbon stock and soil carbon dioxide (CO2) efflux in Acacia mangium Willd and Schizolobium parahyba var. amazonicum at different spacings. The study was conducted in Dom Eliseu, Pará, whose climate has a mean annual temperature around 25 ºC, annual rainfall varies from 2250 to 2500 mm; predominant soil is A moderate typic dystrophic Oxisol loamy soil. In this study we selected two species (A. mangium and S. parahyba var. Amazonicum) at two spacings (4.0 x 2.0 m and 4.0 x 3.0 m) with two replications, resulting in 4 treatments and 8 plots studied for a period of one year, from 2.5 to 3.5 years old. The plots measured 48 m x 60 m. We measured: height, diameter at breast height, soil CO2 flux, and estimated aboveground carbon stock. Mean soil CO2 efflux in plantations of A. mangium was 5.61 ± 1.30 Mg C ha-1 yr-1, and for S. parahyba the overall average was 7.07 ± 1.50 Mg C ha-1 yr-1. Annual accumulation of carbon in above-ground biomass A. mangium was 16.41 ± 1.16 and 14.03 ± 0.82 Mg C ha-1 yr-1 in 4.0 x 2.0 m and 4.0 x 3.0 m and 3.0 m, respectively. In S. parahyba the annual accumulation rate was 8.93 ± 1.87 Mg C ha-1 yr-1. A. mangium plantations accumulated more carbon in aboveground biomass than S. parahyba, with lower annual soil CO2 efflux smaller in relation to S. parahyba in both spacings. Overall A. mangium plantations in the 4.0 x 2.0 m spacing are recommended for carbon sequestration projects. In relation to S. parahyba, the 4.0 x 3.0 m would be recommended due to the same efficiency in carbon sequestration with lower requirement of inputs (seedlings) compared to 4.0 x 2.0 m. Continuos monitoring of the studied plantations would be very suitable to better understand the carbon dynamics.
Acesso aberto (Open Access)
Recuperação de áreas de reserva legal: influência da densidade nos indicadores ambientais do plantio de Sclerolobium paniculatum Vogel
(Universidade Federal do Pará, 2014-06-30) NARDUCCI, Tainah Silva; BRIENZA JÚNIOR, Silvio; http://lattes.cnpq.br/1750852376922258
The legal reserve is an area located within farm, provided the Brazilian Forest Code, which must be protected and present covered by natural vegetation, necessary for the conservation, protection of fauna and flora and rehabilitation of ecological processes, and serve as for ecological corridors for the gene flow species. Many properties have these deforested areas, altered and in advanced stages of degradation, making it important to study the behavior of plantations of fast-growing species in order to accelerate the restoration of natural vegetation and propose more effective techniques to recover these areas. This study aimed to evaluate the influence of homogeneous density planting Sclerolobium paniculatum Vogel, at seven and a half years old, as a catalyst effect of the regeneration process. The experiment is located in Genesis Farm, Dom Eliseu, Pará. Avaluated the growth and investigate that precipitation interferes with the diametric growth of the trees, it was installed in blocks, random plots with four replicates per treatment. To characterize the floristic composition, richness, diversity and similarity of natural regeneration under plantation were installed in each treatment (spacing), plots with eight repetitions for three classes of evaluation of regeneration. And to characterize the floristic composition, richness, diversity and similarity of the soil seed bank were installed randomly eight points of the soil collect with four replications for each treatment, were collect four composite samples from eight and taken to the greenhouse at Embrapa - CPATU which were placed in plastic trays and watered daily, this experiment was a period of four months and every thirty days the germinated seedlings were counted and identified by a botanical. The trees were higher in the 4m x 2m spacing, larger diameter in the spacing 4m x 3m, greater survival in 4m x 4m spacing. Natural regeneration showed a greater similarity in floristic composition between spacings 4m x 2m and 4m x 3m, the values of Shannon diversity index were high and did not differ statistically between the spacings. The seed bank showed greater richness of seedlings in the spacing 4m x 3m, greater similarity in composition between spacings 4m x 2m and 4m x 4m. The species diversity at level 5% of significance did not differ between the spacings. The results demonstrated that the areas have been recovered and that some techniques may be applied seeking to reduce costs and through appropriate management will can accelerate the ecological processes of natural regeneration.