Sabiia Seb
PortuguêsEspañolEnglish
Embrapa
        Busca avançada

Botão Atualizar


Botão Atualizar

Ordenar por: 

RelevânciaAutorTítuloAnoImprime registros no formato resumido
Registros recuperados: 60
Primeira ... 123 ... Última
Imagem não selecionada

Imprime registro no formato completo
A digital atlas to link ontogenic shifts in fish spatial distribution to the environment of the eastern English Channel. Dab, Limanda limanda as a case-study ArchiMer
Martin, Corinne; Vaz, Sandrine; Koubbi, Philippe; Meaden, Geoff; Engelhard, Georg H.; Lauria, Valentina; Gardel, Laure; Coppin, Franck; Delavenne, Juliette; Dupuis, Ludovic; Ernande, Bruno; Foveau, Aurelie; Lelievre, Stephanie; Morin, Jocelyne; Warembourg, Caroline; Carpentier, Andre.
The eastern English Channel, which connects the Atlantic Ocean to the North Sea through the Dover Strait, is an area where numerous and often conflicting human activities take place. A cross-border multidisciplinary project called CHARM was initiated to provide knowledge and tools for planners and decision-makers to durably manage the shared marine living resources. One such tool was an atlas of fish spatial distributions and modelled habitats, which was used here to investigate ontogenic and seasonal shifts in fish spatial distribution and habitat through a case-study, the dab Limanda limanda. Survey data for several life-history stages (eggs, larvae, coastal nurseries, < and > 1 year old) and seasons were used to map spatial patterns (using...
Tipo: Text Palavras-chave: Pleuronectidae; Limanda limanda; Eastern Channel; Spatial distribution; Modelling; Kriging; Ichthyoplankton; Trawl; CUFES.
Ano: 2010 URL: http://archimer.ifremer.fr/doc/00008/11942/8646.pdf
Imagem não selecionada

Imprime registro no formato completo
A regional-scale assessment of digital mapping of soil attributes in a tropical hillslope environment. Repositório Alice
CARVALHO JUNIOR, W. de; LAGACHERIE, P.; CHAGAS, C. da S.; CALDERANO FILHO, B.; BHERING, S. B..
The purpose of this study was to analyze the relationships between soil attributes and environmental covariates in a tropical hillslope environment on a regional scale to estimate spatial distribution of soil attributes and identify statistical and geostatistical techniques that could represent the variation of the soil attributes. The studywas performed in Bom Jardim County, Brazil, and covered an area of 390 km2 with a soil database of 208 sample points distributed in six depth layers (0.53 pts/km2). The study used 18 environmental covariates derived from DEM and satellite imagery. The models evaluated were linear regression, regression trees and ordinary and regression kriging. An exploratory analysis showed that DEM, NDVI, MRVBF, MSP, b3/b2, b5/b7,...
Tipo: Artigo em periódico indexado (ALICE) Palavras-chave: GlobalSoilMap.Net; Kriging; Linear models; Regression tree.
Ano: 2014 URL: http://www.alice.cnptia.embrapa.br/handle/doc/988756
Imagem não selecionada

Imprime registro no formato completo
Alterations and spatial variability of soil fertility in successive years under no tillage system Bragantia
Chiba,Marcio Koiti; Vieira,Sidney Rosa; González,Antonio Paz; Dechen,Sonia Carmela Falci; Maria,Isabella Clerici de.
This study was carried out in order to assess the spatial variability of some soil properties after adoption of no tillage system (NTS). A 19,200 m² plot was marked with a 20 x 20 m spacing grid. Crop yield and soil attributes, at 0-0.2 m deep layer, were measured in 63 points in 1985, 1987 and 1988. The spatial variability was assessed by semivariogram calculation using geostatistics. Soil base saturation index (BS) was interpolated by kriging and also, using a bivariate geostatistical method, the collocated cokriging (CLCK) using terrain elevation as ancillary data. Although, the coefficient of variation (Cv) for soil organic matter content decreased from 1985 (20.4%) to 1988 (10.7%), its mean value increased 32% in the same period. The soil fertility in...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Geostatistics; Kriging; Cokriging.
Ano: 2010 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052010000500005
Imagem não selecionada

Imprime registro no formato completo
Análise de correspondência - uma ferramenta útil na comparação de mapas de produtividade. Infoteca-e
CARVALHO, J. R. P. de; VIEIRA, S. R.; MORAN, R. C. C. P..
O objetivo deste trabalho é apresentar a análise de correspondência como um método estatístico multivariado que pode ajudar na comparação de mapas de produtividade.
Tipo: Comunicado Técnico (INFOTECA-E) Palavras-chave: Análise de correspondência; Mapa de produtividade; Krigagem; Variabilidade temporal; Variabilidade espacial; Análise multivariada; Yield mapping; Kriging; Variability; Multivariate analysis.
Ano: 2001 URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/7817
Imagem não selecionada

Imprime registro no formato completo
Analysis of the spatial variability of crop yield and soil properties in small agricultural plots Bragantia
Vieira,Sidney Rosa; Paz Gonzalez,Antonio.
The objective of this study was to assess spatial variability of soil properties and crop yield under no tillage as a function of time, in two soil/climate conditions in São Paulo State, Brazil. The two sites measured approximately one hectare each and were cultivated with crop sequences which included corn, soybean, cotton, oats, black oats, wheat, rye, rice and green manure. Soil fertility, soil physical properties and crop yield were measured in a 10-m grid. The soils were a Dusky Red Latossol (Oxisol) and a Red Yellow Latossol (Ultisol). Soil sampling was performed in each field every two years after harvesting of the summer crop. Crop yield was measured at the end of each crop cycle, in 2 x 2.5 m sub plots. Data were analysed using semivariogram...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Spatial variability; Kriging; Yield map; Semivariogram.
Ano: 2003 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052003000100016
Imagem não selecionada

Imprime registro no formato completo
Assessing understory development in forest plantations using laser imaging detection and ranging (LiDAR) RChHN
HERNÁNDEZ,JAIME; ACUÑA,M. PAZ; CORVALÁN,PATRICIO; SIMONETTI,JAVIER A.
Forestry plantations are expected to be managed in ways to conserve biodiversity while producing goods and services. This goal implies a significant challenge as plantations tend to reduce species richness. The presence of well developed understory enhances the value of plantations as habitat for native fauna. Here, we develop a straightforward method to assess the availability of understory in forestry stands using laser imaging detection and ranging (LiDAR) data and aerial RGB high resolution images. Based on field and airborne acquired data for Pinus radiata stands in central Chile, the digital crown model (DCM), derived from the subtraction of the digital terrain model (DTM) from the digital surface model (DSM) is a more reliable predictor of...
Tipo: Journal article Palavras-chave: Forestry plantations; Kriging; LiDAR; Pinus radiata; Understory height.
Ano: 2013 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2013000400005
Imagem não selecionada

Imprime registro no formato completo
Effect of Agricultural Intervention on the Spatial Variability of some Soils Chemical Properties in the Eastern Plains of Colombia Chilean J. Agric. Res.
Camacho-Tamayo,Jesús H; Luengas,Carlos A; Leiva,Fabio R.
Growing demand for food exerts pressure on natural resources and may lead to the expansion of agricultural frontiers in developing countries. Most of this pressure appears in tropical zones, in native savannahs, with naturally infertile soils prone to degradation. Crop management in these regions is based on generalized estimates, leaving aside the inherent soil variability, leading to low production efficiency and high risk of environmental damage. This study aims at determining the spatial variability of some chemical properties, including organic carbon, pH, exchangeable acidity, exchangeable aluminum, P, Ca, Mg, K and Na for two Oxisols with different levels of agricultural intervention, in Puerto Lopez, Colombia, in order to identify guidelines for...
Tipo: Journal article Palavras-chave: Geostatistics; Kriging; Soil management; Precision agriculture; Kriging.
Ano: 2008 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000100005
Imagem não selecionada

Imprime registro no formato completo
Environmental Correlation and Spatial Autocorrelation of Soil Properties in Keller Peninsula, Maritime Antarctica Rev. Bras. Ciênc. Solo
Moraes,André Geraldo de Lima; Francelino,Marcio Rocha; Carvalho Junior,Waldir de; Pereira,Marcos Gervasio; Thomazini,André; Schaefer,Carlos Ernesto Gonçalves Reynaud.
ABSTRACT: The pattern of variation in soil and landform properties in relation to environmental covariates are closely related to soil type distribution. The aim of this study was to apply digital soil mapping techniques to analysis of the pattern of soil property variation in relation to environmental covariates under periglacial conditions at Keller Peninsula, Maritime Antarctica. We considered the hypothesis that covariates normally used for environmental correlation elsewhere can be adequately employed in periglacial areas in Maritime Antarctica. For that purpose, 138 soil samples from 47 soil sites were collected for analysis of soil chemical and physical properties. We tested the correlation between soil properties (clay, potassium, sand, organic...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Kriging; Geostatistical methods; Soil variability.
Ano: 2017 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832017000100316
Imagem não selecionada

Imprime registro no formato completo
Evaluación del contenido de mercurio en suelos y lechos de quebradas en la zona minera de Miraflores, Quinchía, Colombia Acta Agron. (Palmira)
Camargo García,Juan Carlos; Arias Morales,Jennifer Paola; Muñoz Paredes,Dein.
En la vereda Miraflores, municipio de Quinchía, Risaralda, donde se ha realizado minería aurífera de forma artesanal durante más de tres décadas, se evaluó el contenido de mercurio (Hg) en suelos y lechos de quebradas. Para el efecto se realizó un muestreo sistemático considerando montajes de minería activa, inactiva y áreas sin intervenir. Igualmente se hicieron observaciones en las partes altas, medias y bajas en lechos de quebradas naturales y drenajes formados artificialmente por el desvío de cauces. Los promedios de los valores de Hg (7.1 mg/kg) fueron más altos en aquellos lugares aledaños a los montajes y cuando la precipitación aumentó. Aunque en Colombia existe poca información y normatividad relacionada con la contaminación de suelos, los valores...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Contaminación de suelos; Degradación de suelos; Minería; Kriging.
Ano: 2015 URL: http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-28122015000200008
Imagem não selecionada

Imprime registro no formato completo
Evaluation of corn production parameters and their spatial relatioship with chemical attributes of the soil. Repositório Alice
MARTINS, A. L. da S.; MOURA, E. G. de; CAMACHO-TAMAYO, J. H..
The characterization of the soil spatial variability allows a better understanding of the relationships between the soil attributes and the environment. The objective of the study was to evaluate the spatial variability of corn production parameters and their relationship with soil chemical attributes. The study was carried out in the municipality of Miranda do Norte (MA, Brazil) in a Typic Plinthaquults. A mesh of 113 points was designed, taking samples at regular distances of 10 m, determining pH, organic material, P, K, Ca, Mg, and exchangeable acidity. The corn production parameters were ear weight, weight of 100 grains, and yield. The results were analyzed by means of descriptive statistics and geostatistical techniques. The pH and the weight of 100...
Tipo: Artigo em periódico indexado (ALICE) Palavras-chave: Precision agriculture; Spatial structure; Zea Mays L.; Kriging.
Ano: 2011 URL: http://www.alice.cnptia.embrapa.br/handle/doc/921474
Imagem não selecionada

Imprime registro no formato completo
Evaluation of statistical and geostatistical models of difgital soil properties mapping in tropical mountain regions. Repositório Alice
CARVALHO JUNIOR, W. de; CHAGAS, C. da S.; LAGACHERIE, P.; CALDERANO FILHO, B.; BHERING, S. B..
As propriedades dos solos têm grande impacto sobre aspectos econômicos e ambientais da produção agropecuária. As relações quantitativas entre as propriedades dos solos e os fatores que condicionam sua variabilidade são a base do mapeamento digital de solos. Os modelos preditivos de propriedades dos solos avaliados neste trabalho são os estatísticos (Regressão Linear Múltipla-RLM) e geoestatísticos (krigagem ordinária e cokrigagem). Este estudo foi desenvolvido para o município de Bom Jardim, RJ, e usou um banco de dados de solos com 208 pontos amostrais. Foram avaliados modelos preditivos para as frações areia, silte e argila, pH em água e carbono orgânico para seis profundidades, de acordo com as especificações do consórcio de mapeamento digital de solos...
Tipo: Artigo em periódico indexado (ALICE) Palavras-chave: Multiple linear regression; Kriging; Co-Kriging; Regressão linear múltipla; Krigagem; Cokrigagem.
Ano: 2014 URL: http://www.alice.cnptia.embrapa.br/handle/doc/992445
Imagem não selecionada

Imprime registro no formato completo
Evaluation of statistical and geostatistical models of digital soil properties mapping in tropical mountain regions Rev. Bras. Ciênc. Solo
Carvalho Junior,Waldir de; Chagas,Cesar da Silva; Lagacherie,Philippe; Calderano Filho,Braz; Bhering,Silvio Barge.
Soil properties have an enormous impact on economic and environmental aspects of agricultural production. Quantitative relationships between soil properties and the factors that influence their variability are the basis of digital soil mapping. The predictive models of soil properties evaluated in this work are statistical (multiple linear regression-MLR) and geostatistical (ordinary kriging and co-kriging). The study was conducted in the municipality of Bom Jardim, RJ, using a soil database with 208 sampling points. Predictive models were evaluated for sand, silt and clay fractions, pH in water and organic carbon at six depths according to the specifications of the consortium of digital soil mapping at the global level (GlobalSoilMap). Continuous...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Multiple linear regression; Kriging; Co-Kriging.
Ano: 2014 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832014000300003
Imagem não selecionada

Imprime registro no formato completo
Evaluation of the spatial dependence of dendrometric characteristics for an Eucalyptus plantation Agronomy
Souza, Rodolfo Marcondes Silva; Almeida, André Quintão de; Ribeiro, Aristides; Souza, Eduardo Soares de; Leite, Fernando Palha.
Geostatistics evaluates the spatial dependence between two or more variables in order to estimate unknown values in space. The objective of this study was to evaluate, using geostatistical techniques, the spatial variability of dendrometric characteristics for a commercial plantation of Eucalyptus grandis x Eucalyptus urophylla located  in eastern Minas Gerais, Brazil (19º28’ S and 42º49’ W). The diameter at breast height (DBH) and commercial height (H) of 60 trees was measured in a forest inventory plot at two, five and seven years old. The volume of each tree in the plot was estimated from allometric equations and values of DBH and H. Spatial dependence of the three dendrometric variables at different ages was evaluated by fitting the experimental...
Tipo: Info:eu-repo/semantics/article Palavras-chave: 5.00.00.00-4 geostatistics; Kriging; Precision forestry. Geoestatística.
Ano: 2015 URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/19676
Imagem não selecionada

Imprime registro no formato completo
Finding suitable transect spacing and sampling designs for accurate soil ECa mapping from EM38-MK2. Repositório Alice
RODRIGUES, H. M.; VASQUES, G. de M.; OLIVEIRA, R. P. de; TAVARES, S. R. de L.; CEDDIA, M. B.; HERNANI, L. C..
Finding an ideal sampling design is a crucial stage in detailed soil mapping to assure reasonable accuracy of resulting soil property maps. This study aimed to evaluate the influence of sampling designs and sample sizes on the quality of soil apparent electrical conductivity (ECa) maps from an electromagnetic sensor survey. Twenty-six (26) parallel transects were gathered in a 72-ha plot in Southeastern Brazil. Soil ECa measurements using an on-the-go electromagnetic induction sensor were taken every second using sensor vertical orientation. Two approaches were used to reduce the sample size and simulate kriging interpolations of soil ECa. Firstly, the number of transect lines was reduced by increasing the distance between them; thus, 26 transects with 40...
Tipo: Artigo em periódico indexado (ALICE) Palavras-chave: Sensoriamento proximal do solo; Geoestatística; Krigagem; Incerteza; Sensoriamento Remoto; Remote sensing; Geostatistics; Kriging; Uncertainty.
Ano: 2020 URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1124782
Imagem não selecionada

Imprime registro no formato completo
Geostatistical analysis of a geochemical dataset Bragantia
Paz-Ferreiro,Jorge; Vázquez,Eva Vidal; Vieira,Sidney Rosa.
The application of geostatistics to data obtained from geochemical prospecting process can provide useful information for evaluating mineralization potential. The objective of this study was to evaluate the spatial distribution of Au, As and Sb contents over a large area of the Coruña province, Spain. A geochemical survey was carried out from which a data set with 323 samples was collected. Macroelements and trace elements were determined by routine analytical techniques. The spatial variability was assessed using semivariogram and cross-semivariogram as well as indicator semivariogram analysis. Frequency distributions of the studied elements departed from normal, as indicated by skewness and kurtosis coefficients. Coefficients of variation ranked as...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Geochemical survey; Geostatistics; Kriging; Indicator kriging; Cokriging.
Ano: 2010 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052010000500013
Imagem não selecionada

Imprime registro no formato completo
Geostatistical characterization of the spatial distribution of Xylella fastidiosa sharpshooter vectors on citrus Neotropical Entomology
Farias,Paulo R.S.; Roberto,Sérgio R.; Lopes,João R.S.; Perecin,Dilermando.
The spatial distribution of the three principal species of sharpshooter (Dilobopterus costalimai Young, Acrogonia sp. e Oncometopia facialis Signoret), vectors of Xylella fastidiosa causal agent of Citrus Variegated Chlorosis, was studied by using geostatistics. The evaluations were carried out in a commercial 'Pera' sweet orange (Citrus sinensis [L.] Osb.) grove budded on Rangpur lime (Citrus limonia Osb.) located at Bebedouro, São Paulo state, aiming to establish better means for vector and disease control. The sharpshooters were monitored using with 50 uniformly distributed 3" x 5" yellow sticky traps hanging down in branches at 1.5 m up to the ground, which were replaced monthly. Acrogonia sp. was the prevalent species sampled. The results were used to...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Citrus Variegated Chlorosis; Citrus sinensis; Semivariogram; Kriging.
Ano: 2004 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1519-566X2004000100004
Imagem não selecionada

Imprime registro no formato completo
Geostatistics as a basis to the CMLS pesticide simulation model with validation in soil columns Scientia Agricola
Nicolella,Gilberto; Perez Filho,Archimedes; Souza,Manoel Dornelas de; Ferracini,Vera Lúcia.
The use of simulation models is probably the most efficient means for predicting the behavior of pesticides in the soil-plant-water system. The CMLS (Chemical Movement in Layered Soils) simulation model for predicting the fate of pesticides was used for studying the behavior of tebuthiuron, a herbicide used in sugar cane crops, from a sampling grid with 111 sampling points 200 m apart from one another and encompassing three types of soil: Ustic Quartzipsamment, Rhodic Hapludox and Typic Hapludox, all with medium and clay textures. The 373 points assessed by the simulator, generated from samples coming from the original grid and through the geostatistical methods of variography and ordinary kriging, returned the depth values reached by the herbicide after...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Microbasin; Sugar cane; Tebuthiuron; Variography; Kriging.
Ano: 2005 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162005000100010
Imagem não selecionada

Imprime registro no formato completo
IDENTIFICATION OF AGRONOMIC MANAGEMENT UNITS BASED ON PHYSICAL ATTRIBUTES OF SOIL J. Soil Sci. Plant Nutr.
Cucunubá-Melo,J.L; Álvarez-Herrera,J.G; Camacho-Tamayo,J.H.
Oil palm (Elaeis guineensis Jacq) is an alternative for the development of productive systems in the tropics. By determining the spatial variability of physical characteristics of soil, specific recommendations for certain areas within a zone can be made. Geostatistical analysis can determine the existence and characteristics of the spatial distribution and is an appropriate tool for analyzing the spatial variability of soil properties. The aim of this study was to determine areas with homogeneous physical characteristics in order to establish agricultural management units, using geostatistical techniques. For this study, 62 samples were collected in 10.6 ha in the municipality of El Reten (Magdalena, Colombia). The properties analyzed were: content of...
Tipo: Journal article Palavras-chave: Geoestatistics; Semivariogram; Kriging; Precision farming; Elaeis guineensis Jacq.
Ano: 2011 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-95162011000100008
Imagem não selecionada

Imprime registro no formato completo
Improvement ocean wave spectra estimation using the temporal structure of wave systems ArchiMer
Kpogo Nuwoklo, Komlan Agbéko; Ailliot, Pierre; Olagnon, Michel; Guede, Zakoua; Arnault, Sabine.
Sea states are usually the combination of several time-evolving wave systems whereas the classical spectral estimation methods assume stationarity. A method that adapts to the dynamical evolution of the spectral components is proposed to improve both omnidirectional and directional sea wave spectral estimations. In this method, periodograms are computed for each sea state as in the conventional methods, and rather than only smoothing individual periodograms, the overall time-history of periodograms are simultaneously smoothed in frequency and time dimensions. Since a simple two dimensional averaging would not be appropriate because the temporal evolution of the wave systems reflects typical non-stationary behaviors, we use either kriging or adaptive 2D...
Tipo: Text Palavras-chave: Directional wave spectrum; Spectral estimation; Periodogram smoothing; Kriging.
Ano: 2015 URL: http://archimer.ifremer.fr/doc/00252/36309/37313.pdf
Imagem não selecionada

Imprime registro no formato completo
Infestation maps and spatial stability of main weed species in maize culture Planta Daninha
Calha,I.M.; Sousa,E.; González-Andújar,J.L..
A study on the spatial distribution of the major weeds in maize was carried out in 2007 and 2008 in a field located in Golegã (Ribatejo region, Portugal). The geo-referenced sampling focused on 150 points of a 10 x 10 m mesh covering an area of 1.5 ha, before herbicide application and before harvest. In the first year, 40 species (21 botanical families) were identified at seedling stage and only 22 during the last observation. The difference in species richness can be attributed to maize monoculture favouring reduction in species number. Three of the most representative species were selected for the spatial distribution analysis: Solanum nigrum, Chenopodium album and Echinochloa crus-galli. The three species showed an aggregated spatial pattern and spatial...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Geo-statistics; Kriging; Precision agriculture; Chenopodium album; Echinochloa crus-galli; Solanum nigrum.
Ano: 2014 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582014000200004
Registros recuperados: 60
Primeira ... 123 ... Última
 

Empresa Brasileira de Pesquisa Agropecuária - Embrapa
Todos os direitos reservados, conforme Lei n° 9.610
Política de Privacidade
Área restrita

Embrapa
Parque Estação Biológica - PqEB s/n°
Brasília, DF - Brasil - CEP 70770-901
Fone: (61) 3448-4433 - Fax: (61) 3448-4890 / 3448-4891 SAC: https://www.embrapa.br/fale-conosco

Valid HTML 4.01 Transitional