Dissertações em Ciências Ambientais (Mestrado) - PPGCA/IG
URI Permanente para esta coleçãohttps://repositorio.ufpa.br/handle/2011/2855
O Mestrado Acadêmico em Ciências Ambientais teve início em 2005 e funciona no Programa de Pós-Graduação em Ciências Ambientais (PPGCA) do Instituto de Geociências (IG) da Universidade Federal do Pará (UFPA) em parceria com o Museu Paraense Emílio Goeldi (MPEG) e a Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA/Amazônia Oriental).
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Item Acesso aberto (Open Access) Comunidade de insetos bentônicos em igarapés do nordeste paraense - Amazônia Oriental(Universidade Federal do Pará, 2012-08-31) MONTELES, Josinete Sampaio; GERHARD, Pedro; http://lattes.cnpq.br/5621269098705408This study aimed to know the community of benthic insects in 17 streams in northeastern Pará, Eastern Amazonia under different land uses and investigate the variations in the abundance, richness and diversity of aquatic insect community to vegetation cover the immediate surrounding area (riparian zone) and landscape (slopes of the watershed where it enters the stream sampled). The benthic macroinvertebrates were collected between July and October 2010, the period of lowest rainfall. At each point were made to 10 Surber samples for quantitative analysis and three hand-net only qualitative character. To evaluate differences between the richness, EPT abundance and diversity, we used an ANOVA and cluster analysis to summarize the biotic data. For differences in the scales of study were then used an ANOSIM and routine SIMPER. Environmental characteristics were also evaluated searching to correlate them to the taxonomic composition and distribution of taxa by Canonical Correspondence Analysis (CCA). A total of 46,371 individuals were collected, in which 11,384 with Surber, distributed in 61 taxa with a predominance of aquatic insects. The highest abundances were observed Chironomidae, Ephemeroptera, Trichoptera and Coleoptera. Abundance, richness and EPT were greater in sections of streams to riparian vegetation and watershed predominantly of igapó anthropic forest (references). The environmental variables of greatest influence on the community were percentage of forest environment in the riparian zone, average water temperature, turbidity, percentage of coarse and fine litter, pH, flow channel and coefficient of variation of channel width. The results showed differences in community composition in relation to different land uses. Through the ecological descriptors, it was detected that the watershed with the highest percentage of anthropic forest area and successional and higher percentage of riparian vegetation surrounding (30m) showed better environmental conditions than those dominated pastures.Item 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/0719395243841543Forest 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.Item Acesso aberto (Open Access) Fluxos hidrogeoquímicos em águas fluviais de microbacias do nordeste paraense e a sua relação com o uso da terra(Universidade Federal do Pará, 2011) BARROSO, Daniel Fernandes Rodrigues; FIGUEIREDO, Ricardo de Oliveira; http://lattes.cnpq.br/2388049759708934The Northeast of Pará is characterized by the Amazonian old settlements, where the slash and burn small farming and large pastures are predominant. Its landscape is dominated by secondary vegetation at a widely succession stage and very few mature forest remnant, which are generally situated along the rivers and streams. In this context, the present study was conducted in fourteen small catchments under different land use and four other small catchments in forested areas under low anthropic impact, with the objective of evaluating the fluvial hydrogeochemistry to support two mesobasins management in the studied region. It was detected that the chemical composition of the evaluated small stream waters is being affected by the agriculture practices adopted in their drainage areas. Hydrogeochemical changing signals were observed for the small catchments where the predominant land uses are: slash-and-burn small farming; crops with irrigation and agrochemical; and cattle farming. Moreover, we observed the importance of the forested catchments for nitrate, chloride and sodium inputs to the studied stream ecosystems. In addition, it was verified a seasonal fluvial hydrogeochemistry variation and strong effects of agriculture systems, especially cattle farming, to the monitored physic-chemical parameters, as the dissolved oxygen concentration decrease, besides the increasing of temperature, pH and electric conductivity. By the results of the present research we can infer that riparian forest is indispensable to mitigate the impacts of the agriculture systems to the water resources, and should be pointed as an important tool in the watershed management, as well as the substitution of slash-and-burn for more sustainable agriculture practices as chop-and-mulching for instance. Finally, we suggest that some of the analyzed parameters can be recommended, according to the focused land use, as environment sustainable indicators of the agriculture systems along the local watershed management in the region.Item 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/1750852376922258The 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.Item Acesso aberto (Open Access) Variação temporal do efluxo de dióxido de carbono CO² do solo em sistemas agroflorestais com palma de óleo (Elaeis guineensis) na Amazônia Oriental(Universidade Federal do Pará, 2013-09-20) SILVA, Carolina Melo da; VASCONCELOS, Steel Silva; http://lattes.cnpq.br/0719395243841543The Amazon region has been subjected to continuous deforestation and expansion of land use for the implementation of activities such as cattle ranching, logging, agriculture, mining and urbanization. The burning and decomposition of forest biomass releases gases that contribute to global warming, such as carbon dioxide (CO2). In this context, there is interest in assessing the dynamics of soil CO2 efflux in the Amazon, especially in oil palm (Elaeis guineensis) agroforestry systems, due to the current large expansion of this crop in the state of Pará, which has become one of the largest producers of the country. This study aimed to investigate the dynamics of soil CO2 efflux in palm oil cultivation in agroforestry systems in the Amazon considering temporal and biotic and abiotic factors that directly influence this process. We quantified biotic factors: microbial biomass, total soil carbon, soil basal respiration, fine root and soil zone of influence of planted species, and abiotic factors: moisture and soil temperature, in two oil palm-based agroforestry systems (adubadeiras and biodiverso systems), during the dry and rainy periods. The results showed that the highest soil CO2 efflux occurred during the rainy season, probably due to increased microbial activity during this period influenced by climatic factors coupled with biotic factors. The biodiverso system showed higher soil efflux than the fertilizer adubadeiras system, probably due to increase biological activity in former system. The soil CO2 efflux showed no strong correlation with the tested variables. It was concluded that the soil CO2 efflux was influenced by rainfall seasonality only. The fact that the systems were be too young (~3 yr-old) may represent the main factor for a lack of stronger relationship of soil CO2 efflux and the variables analyzed.