Alto Universitario

Porto Alegre, Brazil

Alto Universitario

Porto Alegre, Brazil
Time filter
Source Type

Watzlawick L.F.,State University of the Central West | Caldeira M.V.W.,Alto Universitario | De Oliveira Godinho T.,University of Sao Paulo | Balbinot R.,Federal University of Santa Maria
Scientia Forestalis/Forest Sciences | Year: 2012

The aim of this study was to estimate the stock of biomass and organic carbon in a montane mixed shade forest located near General Carneiro, PR. 20 plots of 12 m x 12 m were installed, in which all trees with a CBH (Circumference at Breast Height) ≥ 31.4 cm were felled. From these the following information was obtained: total height, commercial height (agreed as being the morphological inversion point in the natural forest and the height of the first live branch), CBH, identification and collection of herbarium specimens. For the quantification of biomass in the understory and roots, three subunits 1 m x 1 m in each sampling unit were installed (12 m x 12 m) arranged in the lower left corner, center and diagonal upper right corner. To quantify accumulated litter at random, eight samples in each sampling unit were collected (12 m x 12 m), using a metal device measuring 0.25 m x 0.25 m. The montane mixed shade forest has more than 85% of its total biomass and total organic carbon stored in above ground plant structures. The total stock of organic carbon found in this study (104.7 Mg ha -1) demonstrates the importance of maintaining and preserving natural ecosystems as a way of maintaining this stock of organic carbon fixed in plant biomass.

The aim of this paper was to evaluate economical viability and steers performance in grazing receiving supplements with increasing levels of crude protein in the rainy season and its correlation with the pasture ́s composition. The test animals were 21 not castrated steers supplemented with mineral supplement and multiple supplements with 20% and 40% of crude protein and heavy at the beginning and the end of the experiment, after being submitted to fasting from liquids and solids for 14 hours. For analysis of the economic viability was used the difference between the Total Revenue and Total Cost. The protein supplementation didn't influence of the animals performance in grazing. The average daily gain of animals was 0.849 kg. The content of crude protein in the cell wall was negatively correlated with animal performance, and the structural characteristics of the pasture just the mass of forage showed a strong and positive correlation. This activity in the studied period presented economic viability when considered return on capital of 8% a year.

Monteiro P.F.C.,University of Sao Paulo | Monteiro P.F.C.,Federal University of Rio Grande do Sul | Filho R.A.,University of Sao Paulo | Xavier A.C.,Alto Universitario | Monteiro R.O.C.,University of Sao Paulo
Scientia Agricola | Year: 2012

Recently high spectral resolution sensors have been developed, which allow new and more advanced applications in agriculture. Motivated by the increasing importance of hyperspectral remote sensing data, the need for research is important to define optimal wavebands to estimate biophysical parameters of crop. The use of narrow band vegetation indices (VI) derived from hyperspectral measurements acquired by a field spectrometer was evaluated to estimate bean (Phaseolus vulgaris L.) grain yield, plant height and leaf area index (LAI). Field canopy reflectance measurements were acquired at six bean growth stages over 48 plots with four water levels (179.5; 256.5; 357.5 and 406.2 mm) and tree nitrogen rates (0; 80 and 160 kg ha -1) and four replicates. The following VI was analyzed: OSNBR (optimum simple narrow-band reflectivity); NB_NDVI (narrow-band normalized difference vegetation index) and NDVI (normalized difference index). The vegetation indices investigated (OSNBR, NB_NDVI and NDVI) were efficient to estimate LAI, plant height and grain yield. During all crop development, the best correlations between biophysical variables and spectral variables were observed on V4 (the third trifoliolate leaves were unfolded in 50 % of plants) and R6 (plants developed first flowers in 50 % of plants) stages, according to the variable analyzed.

Formigoni M. H.,Alto Universitario | Xavier A.C.,Federal University of Espirito Santo | de Souza Lima J.S.,Federal University of Espirito Santo
Ciencia Florestal | Year: 2011

The Brazilian Northeast (NEB) region presents different vegetation types that are important to maintain this ecosystem. With remote sensing techniques it is possible to analyze variations in vegetation community and alterations in vegetation phenology. The main objective of this work is to evaluate the temporal behavior of the Enhanced Vegetation Index (EVI) from Moderate Resolution Imaging Spectroradiometer (MODIS) of different vegetation types in the NEB over the period ranging from February/2000 to July/2006. The study area was a 1,800 km long transect at latitude -6°41'24' enclosed at the NEB region. A map of Brazil (1:5,000,000 scale, from Brazilian Institute of Geography and Statistics, IBGE) was used to characterize the vegetation types. A total of 144 cloud-free EVI images with spatial resolution of 250 m were acquired from National Aeronautics and Space Administration (NASA). The results showed that: i) EVI data were sensible to the vegetation types; ii) amazon vegetation presented lesser variation in the multi-temporal EVI, however with greater values; iii) Caatinga vegetation presented greater EVI values variation.

da Silva A.F.,Federal University of Espirito Santo | de Souza Lima J.S.,Alto Universitario | de Oliveira R.B.,São Paulo State University
Idesia | Year: 2010

There are many methods used to estimate values in places no sampled for construction of contours maps. The aim of this study was to use the methods of interpolation kriging, inverse of the square of the distance and polynomial in the representation of the spatial variability of the pH of the soil in the organic and conventional management in the culture of the coffee plantation. For that, irregular meshes were built for soil sampling in the depth of 0-0,10 meters, totaling 40 points sampling in each area. For gauging of the interpolation methods they were solitary 10% of the total of points, for each area. Initially, the data were appraised through the classic statistics (descriptive and exploratory) and spatial analysis. The method inverse square of the distance and kriging has low error in estimating dados. The method of kriging presented low variation around the average in different managements.

Duffles P.,Federal University of Rio de Janeiro | Duffles P.,Alto Universitario | Trouw R.A.J.,Federal University of Rio de Janeiro | Mendes J.C.,Federal University of Rio de Janeiro | And 2 more authors.
Precambrian Research | Year: 2016

The Embu Complex crops out in the southeastern part of São Paulo state in Brazil and consists mainly of Neoproterozoic metasedimentary rocks belonging to the interference zone between the Brasilia and Ribeira fold belts. We present U-Pb ages (LA-IPCMS) supported by cathodoluminescence images for detrital zircon from these rocks in order to constrain the formation and evolution of the source area of this complex. In this paper we choose to individualize within the Embu Complex a Paleoproterozoic basement, a metasedimentary sequence, the Embu Sequence, and Neoproterozoic intrusive bodies, now largely orthogneisses. Six distinct rock types were recognized in the Embu Sequence: biotite gneiss, biotite schist, quartzite, amphibolite, calc-silicate rock and talc schist. The sequence is strongly deformed by several deformation phases and metamorphosed into amphibolite facies. An important shear zone, the Buquira Shear zone, separates the Embu Complex from the Socorro-Guaxupé Nappe, to the north, considered to be part of the upper plate of the southern Brasília belt collision. However, our mapping showed that the shear zone cuts obliquely into the Embu Complex, diminishing considerably its regional importance. Three samples were separated for dating, a schist north of the shear zone and two quartzites south of the shear zone. The results show that the ages of detrital zircon of these samples are mainly Paleoproterozoic, with a minor Archean component. The youngest igneous zircon grain from the schist produced an age of about 1000 Ma, indicating the maximum sedimentation age for the sequence. No significant difference appears between the samples north and south of the shear zone, reforcing the interpretation that this zone is only of local importance. Important metamorphic overgrowth of zircon in the age range 670-640 is present in all three samples; it is interpreted as related to the installment of a continental magmatic arc in the Socorro-Guaxupé Nappe and in the Embu Complex. A second metamorphic pulse between 621 and 599 Ma is only apparent in one sample. According to the literature this was the period of continental collision between the Paranapanema and São Francisco paleocontinents leading to the formation of the southern Brasília belt. Possibly the fact that the analyzed samples are localized some 30 km away from the suture, in the upper plate, explains that the increase in temperature during the collision in this area was insufficient to grow significant new zircon. A third metamorphic pulse with ages of 576-574 Ma, possibly related to collision in the Ribeira belt, is only detected in three analyses of metamorphic rims in the schist sample. Earlier reported ages of about 790 Ma, both for igneous crystallization and metamorphism in a more westerly part of the Embu Complex, are only recognized in one analysis of metamorphic overgrowth (794 ± 24 Ma) from the schist sample, and two probably hybrid analyses of 830 ± 19 Ma and 767 ± 14 Ma from the northern quartzite sample. It is concluded that the results show that the detritic zircon is probably derived from the Paranapanema Paleocontinent. © 2016 Elsevier B.V.

Cabral P.D.S.,UENF FAPERJ | Soares T.C.B.,Campus Universitario | Lima A.B.P.,Alto Universitario | Soares Y.J.B.,UENF FAPERJ | da Silva J.A.,Alto Universitario
Revista Ciencia Agronomica | Year: 2011

Fifty-eight genotypes of common bean (Phaseolus vulgaris L.), being 32 local genotypes, 20 genotypes from EMBRAPA and six commercial cultivars were evaluated in Alegre/ES, through the influence of eight characters of agronomic importance to grain production by unit area. The experiment was conducted in a randomized block design with three replications in the wet period of 2008/09 crop year. This study aimed to estimate the path coefficients between the primary and secondary characters on grain yield. The primary characters were set up by the number of seeds per pod (NSV), weight of one hundred grains (P100), number of pods per plant (NVP) and number of seeds per plant (NSP) and the secondary traits were number of days from germination to flowering (FL), number of days between emergence and harvest maturity (MC), plant height (EP), height of the first pod (PIV). The analysis of the path coefficient showed that the primary character with more direct effect on yield (PROD) was NVP (1.0011), associated with high correlation (0.754). Variables P100 and NSV showed high indirect effect on NVP of 0.8848 and 0.6369, respectively. It was observed an increase in P100 and NVP in plants with short cycle and growing season and first pod height taller, and that the height of the first pod did not significantly influence productivity.

The nitrate accumulation in plant tissues can occur due to low light availability. However, published studies have not linked nitrate accumulation to photosynthetic photon flux (PPF) measured during the growing period. This study aimed to evaluate the effect of the reduction of photosynthetic photon flux and the concentration of nitrate in the nutrient solution on agronomic characteristics and accumulation of nitrate in lettuce grown in hydroponics. The trial design was entirely randomized in a factorial scheme (4 x 2) with three repetitions, and four shading levels: 0, 30, 50, and 80% and two nitrate levels in nutrient solution: 5 and 10 mmol L -1. The dry matter production decreased directly and linearly with the reduction of light. The lowest level in nitrate solution also led to reduction in dry mass yield. The maximum accumulation of nitrate reached 966.3 mg kg -1 fresh mass, with PPF of 118 μmol/m2/s and 140 mg L -1 of N-NO 3 -1 (below the maximum levels recommended by the European Union), and the minimum of 200 mg kg -1 with PPF of 455 μmol/m2/s and 70 mg L -1 of N-NO 3 -1 in the nutrient solution. The reduction of nitrate in the nutrient solution from 140 to 70 mg L -1 led to the reduction of nitrate accumulation in shoots, but also caused a decrease in the production of phytomass of shoots, as well as reduced leaf area significantly.

Guimaraes G.P.,Federal Institute of Espirito Santo IFES | Mendonca E.S.,Alto Universitario | Passos R.R.,Alto Universitario | Andrade F.V.,Alto Universitario
Revista Brasileira de Ciencia do Solo | Year: 2014

Intensive land use can lead to a loss of soil physical quality with negative impacts on soil aggregates, resistance to root penetration, porosity, and bulk density. Organic and agroforestry management systems can represent sustainable, wellbalanced alternatives in the agroecosystem for promoting a greater input of organic matter than the conventional system. Based on the hypothesis that an increased input of organic matter improves soil physical quality, this study aimed to evaluate the impact of coffee production systems on soil physical properties in two Red- Yellow Oxisols (Latossolos Vermelho-Amarelos) in the region of Caparaó, Espirito Santo, Brazil. On Farm 1, we evaluated the following systems: primary forest (Pf1), organic coffee (Org1) and conventional coffee (Con1). On Farm 2, we evaluated: secondary forest (Sf2), organic coffee intercropped with inga (Org/In2), organic coffee intercropped with leucaena and inga (Org/In/Le2), organic coffee intercropped with cedar (Org/Ced2) and unshaded conventional coffee (Con2). Soil samples were collected under the tree canopy from the 0-10, 10-20 and 20-40 cm soil layers. Under organic and agroforestry coffee management, soil aggregation was higher than under conventional coffee. In the agroforestry system, the degree of soil flocculation was 24 % higher, soil moisture was 80 % higher, and soil resistance to penetration was lower than in soil under conventional coffee management. The macroaggregates in the organic systems, Org/In2, Org/In/ Le2, and Org/Ced2 contained, on average, 29.1, 40.1 and 34.7 g kg-1 organic carbon, respectively. These levels are higher than those found in the unshaded conventional system (Con2), with 20.2 g kg-1.

da Castro F.S.,Alto Universitario | Pezzopane J.E.M.,Alto Universitario | Cecilio R.A.,Alto Universitario | Pezzopane J.R.M.,Alto Universitario | Xavier A.C.,Alto Universitario
Revista Brasileira de Engenharia Agricola e Ambiental | Year: 2010

Geostatistics is associated with a class of techniques used to analyze and to infer values of a variable distributed in space or time. By means of this, the objective of this work was to evaluate different techniques of interpolation for the following climatic parameters: precipitation, water deficit, water surplus, potential evapotranspiration, actual evapotranspiration and water availability in the State of the Espirito Santo. Meteorological data of air temperature and precipitation were used in the climatic water balance determination, according to Thornthwaite & Mather (1955), adopting a storage capacity of 100 mm. The results show that the method of kriging was the most efficient for the spatialization of climatic parameters, based on the lower value of the Root of the Mean Quadratic Error (REMQ) and other calculated parameters that helped in choosing the best model.

Loading Alto Universitario collaborators
Loading Alto Universitario collaborators