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Local environmental controls of Atlantic Forest tree community assembly on a coastal continental island in southeastern Brazil Acta Botanica
Nettesheim,Felipe Cito; Garbin,Mário Luís; Pereira,Marcos Gervasio; Araujo,Dorothy Sue Dunn de.
ABSTRACT Tropical forests with high species diversity are commonly found in rugged montane areas. We investigated causes of local tropical forest tree community assembly on a continental island with heterogeneous terrain. We recorded tree community (absolute species abundance), topography, soil, litter and location in 40 sampling units on two opposite sides of the island with similar heterogeneous terrain. We used transformation based Redundancy Analyses and variation partitioning to determine the contribution of environment (topography, soil and litter), spatial structure (geographic location and Moran Eigenvector Maps) and the shared effects of these to explain community assembly. The environment made a significant contribution to explain tree community...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Community composition; Community structure; Floristics; Neutral; Niche; Soil; Spatial structure; Topography; Tropical forest.
Ano: 2019 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062019000100088
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Spatial distribution of seeds and juveniles of Enterolobium glaziovii Bentham (Leguminosae, Mimosoideae) in the Atlantic forest, Brazil Acta Botanica
Ramos,Flavio Nunes; Matos,Dalva M. Silva; Santos,Flavio A.M..
The spatial distribution of fruits and juveniles of Enterolobium glaziovii Bentham were evaluated in four circular plots of 30 m radius, centered around reproductive individuals to determine whether the size of the parental crowns, topography, and canopy coverage influence these patterns. Each crown was subdivided into eight irregular triangles and the area of each was calculated. Each plot was subdivided into four sub-plots, two of them in an up-slope direction, and the other two in a down-slope direction. The canopy coverage for each plot was estimated at breast height (1.30 m) and at ground level, every three months during 1998. The numbers of fruits and juveniles of E. glaziovii were recorded. Although there were more fruit under the parental crown...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Conspecific influence; Crown size; Seed shadow; Topography.
Ano: 2005 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062005000300022
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Spatial variability of the competitive effect of Barley (Hordeum vulgare L.) on Lolium rigidum L. Agrociencia
Izquierdo,Jordi; Fernández-Quintanilla,César.
Lolium rigidum is a major grass weed of winter cereals in the Mediterranean area, in spite of the continuous use of herbicides in these crops. New management approaches focus on the reduction of the seed banks by enhancing crop competitiveness and, consequently, minimizing weed seed rain. However, the spatial heterogeneity that exists within fields results in differences in the growth and the competitiveness of crops and weeds. In order to determine if the competitive interactions between barley and L. rigidum are site-specific biomass and seed production of this weed, growing in monoculture (plots with L. rigidum) and in mixed culture (plots with L. rigidum+barley), were studied at three sites (in upland, mid-slope and lowland positions) within barley...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Hordeum vulgare; Crop competition; Seed rain; Site-specific; Topography; Weed biomass.
Ano: 2010 URL: http://www.scielo.org.mx/scielo.php?script=sci_arttext&pid=S1405-31952010000100004
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Different slopes of a mountain can determine the structure of ferns and lycophytes communities in a tropical forest of Brazil Anais da ABC (AABC)
NETTESHEIM,FELIPE C.; DAMASCENO,ELAINE R.; SYLVESTRE,LANA S..
A community of Ferns and Lycophytes was investigated by comparing the occurrence of species on different slopes of a paleoisland in Southeastern Brazil. Our goal was to evaluate the hypothesis that slopes with different geographic orientations determine a differentiation of Atlantic Forest ferns and lycophytes community. We recorded these plants at slopes turned towards the continent and at slopes turned towards the open sea. Analysis consisted of a preliminary assessment on fern beta diversity, a Non Metric Multidimensional Scaling (NMDS) and a Student t-test to confirm if sites sampling units ordination was different at each axis. We further used the Pearson coefficient to relate fern species to the differentiation pattern and again Student's t-test to...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Atlantic rain forest; Topography; Pteridophytes; Richness; Environmental factors.
Ano: 2014 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652014000100199
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Tree community variation in a tropical continental island according to slope aspect and human interference Anais da ABC (AABC)
GONÇALVES,NATHAN B.; NETTESHEIM,FELIPE C.; CONDE,MARILENA M.S..
ABSTRACT Associating description of unrecorded tropical tree community structure to sampling approaches that can help determine mechanisms behind floristic variation is important to further the comprehension of how plant species coexist at tropical forests. Thus, this study had the goals of (i) evaluating tree community structure on the continental island of Marambaia (23°4’37.09”S; 43°59’2.15”W) and (ii) testing the prediction that there are local scale changes in a tropical tree community structure between slopes facing different geographic orientation and with distinct human interference history. We established 60 (0.6 ha) sampling units in three different slope sites with distinct predominant geographic orientation and human interference. We sampled...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Anthropic impacts; Atlantic Rainforest; Plant diversity; Floristic variation; Topography.
Ano: 2018 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652018000100017
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Jack knifing for semivariogram validation Bragantia
Vieira,Sidney Rosa; Carvalho,José Ruy Porto de; González,Antonio Paz.
The semivariogram function fitting is the most important aspect of geostatistics and because of this the model chosen must be validated. Jack knifing may be one the most efficient ways for this validation purpose. The objective of this study was to show the use of the jack knifing technique to validate geostatistical hypothesis and semivariogram models. For that purpose, topographical heights data obtained from six distinct field scales and sampling densities were analyzed. Because the topographical data showed very strong trend for all fields as it was verified by the absence of a sill in the experimental semivariograms, the trend was removed with a trend surface fitted by minimum square deviation. Semivariogram models were fitted with different...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Semivariograms; Stationarity; Topography; Scale of variation.
Ano: 2010 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052010000500011
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Detrending non stationary data for geostatistical applications Bragantia
Vieira,Sidney Rosa; Carvalho,José Ruy Porto de; Ceddia,Marcos Bacis; González,Antonio Paz.
The use of geostatistics requires at least that the intrinsic hypothesis be satisfied. The presence of a trend in the data invalidates this hypothesis. One of the ways of solving this problem is by subtracting a function fitted to the original data and working with the residuals. This technique also represents a change to a smaller scale of the variability and surface roughness. This paper describes the detrending technique of subtracting a trend surface fitted by the least squares method and discusses the results using topographical data as examples. The objective is to show how the detrending technique works for different scales and degrees of trend and how to interpret the results. It is shown that the simplest the surfaces fitted that does the work of...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Semivariograms; Stationarity; Topography; Scale of variation.
Ano: 2010 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052010000500002
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Spatial variability of soil CO2 emission in different topographic positions Bragantia
Brito,Liziane de Figueiredo; Marques Júnior,José; Pereira,Gener Tadeu; La Scala Junior,Newton.
The spatial variability of soil CO2 emission is controlled by several properties related to the production and transport of CO2 inside the soil. Considering that soil properties are also influenced by topography, the objective of this work was to investigate the spatial variability of soil CO2 emission in three different topographic positions in an area cultivated with sugarcane, just after mechanical harvest. One location was selected on a concave-shaped form and two others on linear-shaped form (in back-slope and foot-slope). Three grids were installed, one in each location, containing 69 points and measuring 90 x 90 m each. The spatial variability of soil CO2 emission was characterized by means of semivariance. Spatial variability models derived from...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Sugarcane; Carbon dioxide; Geostatistics; Kriging; Soil respiration; Topography.
Ano: 2010 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052010000500004
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Canopy gap colonization in the Atlantic Montane Rain Forest BABT
Lima,Renato A. Ferreira de; Moura,Leila Cunha de.
In the Atlantic Montane Rain Forest of South-eastern Brazil, a study was carried out to describe and evaluate canopy gap colonization. Gap composition by herb species was assessed through their soil coverage and woody species by measuring and identifying all individuals taller than one meter. Gap structure (gap size, number and diameter of treefalls), topographic position and surrounding vegetation were also measured. Two genera of Marantaceae were markedly frequent and abundant inside gaps. The more abundant and frequent woody species were shade tolerant. Species-rich families found inside gaps did not differ from the forest as a whole. Results revealed that direct and indirect influences of topography were important to determine gap composition of woody...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Gap floristics; South-eastern Brazil; Marantaceae species; Montane rain forest; Topography.
Ano: 2006 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132006000700013
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The brain decade in debate: VI. Sensory and motor maps: dynamics and plasticity BJMBR
Das,A.; Franca,J.G.; Gattass,R.; Kaas,J.H.; Nicolelis,M.A.L.; Timo-Iaria,C.; Vargas,C.D.; Weinberger,N.M.; Volchan,E..
This article is an edited transcription of a virtual symposium promoted by the Brazilian Society of Neuroscience and Behavior (SBNeC). Although the dynamics of sensory and motor representations have been one of the most studied features of the central nervous system, the actual mechanisms of brain plasticity that underlie the dynamic nature of sensory and motor maps are not entirely unraveled. Our discussion began with the notion that the processing of sensory information depends on many different cortical areas. Some of them are arranged topographically and others have non-topographic (analytical) properties. Besides a sensory component, every cortical area has an efferent output that can be mapped and can influence motor behavior. Although new behaviors...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Visual; Somatosensory; Auditory; Motor; Cortex; Topography; Learning; Synesthesia.
Ano: 2001 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2001001200001
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Topographic distribution of the tibial somatosensory evoked potential using coherence BJMBR
Melges,D.B.; Infantosi,A.F.C.; Miranda de Sá,A.M.F.L..
The objective of the present study was to determine the adequate cortical regions based on the signal-to-noise ratio (SNR) for somatosensory evoked potential (SEP) recording. This investigation was carried out using magnitude-squared coherence (MSC), a frequency domain objective response detection technique. Electroencephalographic signals were collected (International 10-20 System) from 38 volunteers, without history of neurological pathology, during somatosensory stimulation. Stimuli were applied to the right posterior tibial nerve at the rate of 5 Hz and intensity slightly above the motor threshold. Response detection was based on rejecting the null hypothesis of response absence (significance level α= 0.05 and M = 500 epochs). The best detection rates...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Somatosensory response detection; Magnitude-squared coherence; Tibial nerve; Topography.
Ano: 2008 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2008001200004
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The contribution of fire damage to restricting high mountain Polylepis australis forests to ravines: Insights from an un-replicated comparison Ecología austral
Alinari,Julieta; von Müller,Axel; Renison,Daniel.
High mountain forests are often restricted to ravines and much debate has existed on the explanations of this distribution, with arguments ranging from abiotic site conditions being more favorable in ravines to there being reduced herbivory or reduced fre frequency and damage in ravines. We aim at understanding the contribution of fre damage and provide data to help test the hypothesis that fires are less damaging and that trees recover faster in ravines as compared to ridge sites. We evaluated crown damage, post-fire survival, regeneration by resprouts and seeds, and browsed stems in burned and unburned control Polylepis australis trees situated in a ravine and in a ridge forest in the west slope of the mountains of Central Argentina. The proportion of...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Montane woodlands; Regeneration; Topography; Tree line; Sprouting; Ridge.
Ano: 2015 URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S1667-782X2015000100002
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Erosion factors and magnetic susceptibility in differet compartments of a slope in Gilbués-PI, Brazil REA
Santos,Hélio L.; Marques Júnior,José; Matias,Sammy S. R.; Siqueira,Diego S.; Martins Filho,Marcílio V..
The erosion is the degradation of soil with effects on crop productivity and pollution of the environment. To understand the spatial variability of this phenomenon, geostatistical techniques and concepts of soil-landscape can be used to identify landscape compartments with different potential of erosion. The aim of this study was to understand the factors of erosion in landscape compartments and the relations with the magnetic susceptibility (MS) of the soils in a slope in Gilbués, state of Piauí (PI), Brazil. Sampling meshes were set in compartments I and II with 121 points and in compartment III with 99 points spaced every 10 meters. There was significant difference to erodibility (K) and risk of erosion (RE); the spatial variability of MS was lower than...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Indirect quantification; Geostatistics; Conservation planning; Compartments; Topography; Relief; Landscape.
Ano: 2013 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162013000100008
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Isotopic composition of soils and plants in a gallery forest of cerrado biome: effect of topographic gradient. Infoteca-e
PARRON. L. M.; BUSTAMANTE, M. M. C.; CAMARGO, P.; PRADO, C. L.; MARTINELLI, L. A..
Tipo: Folders Palavras-chave: Mata de galeria; Cerrado; Essência Florestal; Química do Solo; Topografia; Forests; Soil chemistry; Topography; Woody plants.
Ano: 2004 URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/568331
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Caracterização geomorfológica do município de Luís Eduardo Magalhães, oeste baiano, escala 1:100.000. Infoteca-e
CASTRO, K. B. DE; MARTINS, E. de S.; GOMES, M. P.; REATTO, A.; LOPES, C. A.; PASSO, D. P.; LIMA, L. A. DE S.; CARDOSO, W. DOS S.; CARVALHO JUNIOR, O. A.; GOMES, R. A. T..
Este trabalho apresenta a caracterização geomorfológica do município de Luís Eduardo Magalhães, BA, na escala 1:100.000. A metodologia utilizada para o mapeamento geomorfológico foi baseada no uso de imagens de altimetria Shuttlle Radas Topografhy Mission (SRTM), de técnicas de geoprocessamento e de trabalhos de campo. A geomorfologia foi caracterizada em três níveis taxonômicos: 1. nível: domínio morfoestrutural, composto pela cobertura sedimentar São Franciscana (100%); 2. nível: regiões geomorfológicas compostas pelas chapadas do São Francisco (28,7%) e 3. nível: unidades geomorfológicas, formado pelas unidades chapadas intermediárias (42%), topos (26%), frente de recuo erosivo (22%), planície intraplanáltica (7%) e veredas (3%). O mapeamento...
Tipo: Folhetos Palavras-chave: Bacia do São Francisco; Landscape; SRTM data; Geotechnology; São Francisco Basin; Geomorfologia; Mapa; Relevo; Brazil; Geomorphology; Topography.
Ano: 2010 URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/891209
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Levantamento preliminar de solos do município de Correntina - BA, escala 1: 100.000 (2009). Infoteca-e
LIMA, L. A. DE S.; MARTINS, E. de S.; BRAGA, A. R. dos S.; CASTRO, K. B. de; PASSO, D. P.; CARDOSO, W. dos S.; SANTANA, O. A.; CARVALHO JÚNIOR, O. A. de; GOMES, R. A. T..
Tipo: Folders Palavras-chave: Solos; Geoprocessamento; Landscape; SRTM data; Geotechnology; Mapping; Geoprocessing; Cartografia; Geomorfologia; Brazil; Geomorphology; Topography.
Ano: 2009 URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/711886
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Mapeamento geomorfológico da bacia hidrográfica do Alto Rio Preto a partir do processamento digital de imagem SRTM. Infoteca-e
LIMA, L. A. DE S.; MARTINS, E. de S.; BRAGA, A. R. dos S.; CASTRO, K. B. DE; SOUZA, V. V. DE.
Tipo: Folders Palavras-chave: Geoprocessamento; Landscape; SRTM data; Geotechnology; Mapping; Geoprocessing; Watershed; Bacia Hidrográfica; Cartografia; Brazil; Geomorphology; Topography.
Ano: 2009 URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/711888
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Ecossistema de pastagem cultivada na Amazônia brasileira. Infoteca-e
FALESI, I. C..
A pesquisa foi realizada em áreas com pastos de idades diferentes, desde meses de idade (formação) ate 11 anos, tomando-se a área com floresta natural como elemento de comparação (testemunha). Foram coletadas amostras de solos de 0-20 cm em cada uma dessas áreas, alem da coleta de perfis pedagógicos ate a uma profundidade de 1,50 m. Apos a obtenção das analises no laboratório, constatou-se que vários nutrientes e índices ou valores, sofreram acréscimos quando o solo foi cultivado com pastagem, melhorando portanto, as suas propriedades químicas. Os elementos que mais se evidenciaram, foram: cálcio, magnésio, fosforo, alumínio, e os índices de pH, V (saturação de bases), S (soma de bases) e saturação de alumínio. Os quadros de analises e gráficos constantes...
Tipo: Livros Palavras-chave: Brasil; Sown pasture; Ecosystem; Fertility; Clima; Ecossistema; Ecologia; Fertilidade; Geologia; Pastagem Cultivada; Topografia; Solo; Vegetação; Amazonia; Climate; Geology; Ecology; Topography; Soil; Vegetation.
Ano: 1976 URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/385693
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Variabilité décennale de la circulation océanique et modes de bassin: Influence de la topographie et de la circulation moyenne ArchiMer
Ferjani, Dhouha.
One of the potential mechanisms at the origin of climatic variability on decadal to multidecadal timescales is the thermohaline oscillation corresponding to large-scale and low frequency basin modes that result from the interaction between long planetary waves and fast inertia-gravity waves during the adjustment process. However, most of the studies dealing with this decadal oscillation were carried out in a simplified flat bottom or reduced-gravity quasigeostrophic context. This dissertation aims to study the effect of bottom topography and mean flow on the characteristics of the gravest baroclinic basin modes of variability in a mid-latitude idealized ocean basin. To that end, we make use of a two-layer shallow water (SW) model. Different bathymetries...
Tipo: Text Palavras-chave: Modèle shallow-water; Analyse de stabilité linéaire; Topographie; Circulation moyenne; Modes de bassin.; Shallow-water model; Linear stability analysis; Topography; Mean flow; Basin modes..
Ano: 2013 URL: http://archimer.ifremer.fr/doc/00160/27092/25259.pdf
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Effects of Monsoon Winds and Topographical Features on the Vertical Thermohaline and Biogeochemical Structure in the Gulf of Tadjourah (Djibouti) ArchiMer
Omar, Youssouf Moussa; Memery, Laurent; Carton, Xavier; Daher, Abdourahman; Duvielbourg, Eric.
The vertical thermohaline and biogeochemical structures of the upper layer (0 - 200 m) were studied in the Gulf of Tadjourah using high-resolution hydrographic data collected in July-August 2013, September 2013 and February 2014. During summer, the superficial layer consisted of the mixed layer (ML) extending to a depth of about 20 - 30 m followed by the thermocline located between 30 and 50 m depth. The ML was thicker in the west and the southeast where the thermal gradient and chlorophyll a concentrations were particularly high. During September, this stratification persisted but the ML became warmer and saltier and the thermocline moved slightly deeper. In February, the ML extended to about 120 m, and the thermocline was less pronounced. A comparison of...
Tipo: Text Palavras-chave: Thermohaline; Biogeochemical Structures; Mixed Layer Depth; Thermocline; Monsoon Wind; Topography.
Ano: 2016 URL: https://archimer.ifremer.fr/doc/00601/71286/69693.pdf
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