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The interactive pedological‑hydrological processes and environmental sensitivity of a tropical isolated wetland in the brazilian cerrado
(2021) Furlan, Lucas Moreira; Rosolen, Vania; Moreira, César Augusto; Bueno, Guilherme Taitson; Ferreira, Manuel Eduardo
In seasonal fooding isolated wetlands, the degree of wetness suggests a close synergy between soil processes, landscape evolution and hydrology along space and time. Until now, that subject has received insufcient attention despite natural wetlands supply essential environmental services to society and are surrounded by intensive agriculture that uses agrochemicals and fertilizers in their management. The objectives of this study were to propose an infltration architecture model based on local surface and subsurface water-fuxes in isolated wetland embedded in lateritic plateau covered by savanna and qualify the environmental sensitivity as an area of aquifer recharge. Grain size, soil bulk density, and hydraulic conductivity were determined in fve profles in a soil catena. Unmanned Aerial Vehicle high-resolution images were obtained to generate a digital elevation model and discriminate areas with diferent vegetation, water accumulation, and environmental sensitivity. Electrical tomography was performed to unveil the soil architecture and infltration. The soils (Plinthosols) developed on aquic conditions determine the linkage between the surface–subsurface hydrodynamics with the soil’s physical properties. We have identifed vertical and lateral water-fows in the soil architecture. Vertical fow occurs exclusively at the center, where the wetland is characterized as a recharge zone. Lateral fow towards the borders characterizes a discharge zone. The recharge zone is a depression surrounded by crops; therefore, it is a point of high environmental sensitivity. This hydrodynamic model is essential to support studies related to the dispersion of contaminants since soybean agriculture dominates the whole area of well-drained soils in the Brazilian Cerrado.
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Variações ecológicas, fitofisionômicas, edáficas e distribuição das espécies em um gradiente ambiental entre campinarana e campina–bacia do rio Demini, AM
(2016) Guimarães, Felipe Silva; Bueno, Guilherme Taitson; Mendes, Débora de Sena Oliveira; Diniz, Alisson Duarte; Souza, Jorge Batista de
Campinas and campinaranas are Amazon phytophysiognomies occurring mainly in the Rio Negro basin. There are a few studies about the floristic composition and origin of these vegetation types. Works that seek to relate the geographical distribution of species and vegetation types with soil variables are even rarer. This work has the following goals: to perform a phytosociological study in an area which has transitions between forested campinarana, wooded campinarana and campina; point the relationships between soil and vegetation characteristics along an ecological gradient that permeates these vegetation types. The study area is located in the center-eastern region of the Barcelosmunicipality. Soil samples were also collected in each parcel center. To analyze the relationship between soil and biotic variables were used the PCA and CCA analysis besides the geoecologic profile. The results suggest the flora of the region seems to beoriginated mainly from Guyana highlands and some species may originate from terra firme forests. There was a significant change in floristic composition and other environmental aspects over the ransect. The variables most related to these changes are the groundwater level and particle size.
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Mapeamento das unidades de paisagem natural na bacia do rio Demini, afluente do rio Negro–AM
(2016-12) Guimarães, Felipe Silva; Bueno, Guilherme Taitson; Mendes, Débora de Sena Oliveira; Souza, Jorge Batista; Diniz, Alisson Duarte
The campinas and campinaranas are ecosystems that occupy large areas in the Rio Negro basin. They are associated with specific soil types such as Gleysols and Spodosols, as well as drainage conditions and specific relief forms yielding particulars landscape units. The goals of this paper are to identify and map the major landscape units in the Middle Demi region considering the components soil, topography and vegetation. It was done transect, from the edge to the center of the plateau was drawn, aiming to cover the greatest environmental variation. Along this transect were installed plots for sampling vegetation, pits and augerings boreholes were made for groundwater measuring, soil sampling, and its description and subsequent classification. The results obtained from the transect were extrapolated to larger area through analysis of a Landsat 7 image. In this image it were used contrast techniques, true color and false color composition besides the calculation of the normalized difference vegetation index. Three landscape units were identified: forested campinarana associated with well-drained Spodosols closer the edges of the low plateaus or lines of drainage incision; wooded campinarana related to bad drained Spodosols; and campinas associated toGleysols in wetlands on the central regions of the plateau.
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Funcionamento hídrico e transferência de matéria em uma vertente no Planalto de Diamantina - Parque Estadual Do Biribiri/Minas Gerais
(2017-06) Soares, Bruna Fernandes; Bueno, Guilherme Taitson; Ferreira Neto, José Alves; Santos, Everton Sena; Nascimento, Nadia Regina do
La connaissance de la dynamique de l'eau et l’étude géochimique des éléments dissous dans les eaux peuvent fournir des informations importantes pour comprendre la genèse et l'evolution du sol que couvre un paysage. Ainsi, cette recherche vise à caractériser ces variables dans un versant du Plateau de Diamantina - MG, en surveillant le comportement du niveau de la nappe phréatique au cours de l'année hydrologique avec piézomètres et mesure des teneurs en éléments chimiques (Al, Fe et Si) par spectrométrie (ICP-OES). Les résultats indiquent que le comportement de la nappe phreátique et le contenu d’éléments en solution sont directement corréles au taux de precipitation et aux cycles de humidification/dessèchement du sol causés par la saisonnalité.
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Uma proposta para automatização do índice de dissecação do relevo
(2017-03) Guimarães, Felipe Silva; Cordeiro, Claudia Mendes; Bueno, Guilherme Taitson; Carvalho, Vilma Lúcia Macagnan; Nero, Marcelo Antônio
The relief dissection index is a morphometric analysis which considers the valley’s depth and the interfluvial average size. Ross (1992, 1994) formalized this index which has several applications, such as relief segmentation, provide bases for the geomorphological mapping, study of the morphogenesis x pedogenesis balance and environmental vulnerability. The analog form of calculation and mapping of the dissection index is extremely costly as well as being subject to human error and differences of interpretation. Currently there is no method to perform fully automated calculation of dissecation index which considers both variables proposed by Ross (valley’s depth and interfluvial average size). The goal of this paper is to present an automation routine calculation of dissection index for each pixel from a digital elevation model. The method is divided into four main stages: the digital elevation model treatment, the mapping of the valley’s depth degree, the interfl uvial average size mapping for each watershed and the integration of these two last products. According to the Ross (1994) proposal, in the end of the mapping, the dissection values must be classified following a scale that ranges from very weak to very strong. When the resulting map of Ross classification was compared to the three-dimensional model of the area, to the slope map and the drainage network we noted some inconsistencies, such as the strong dissection class occurring on flat regions and places where the valley’s depth degree is extremely low. Three other proposals for the dissection values were then suggested.