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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
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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
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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/handle/doc/7817
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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
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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
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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: Journal 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
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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
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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
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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
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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
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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
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Interpoladores geoestatísticos na análise da distribuição espacial da precipitação anual e de sua relação com altitude. Repositório Alice
CARVALHO, J. R. P. de; ASSAD, E. D.; PINTO, H. S..
Resumo - O objetivo deste trabalho foi quantificar a contribuição da variável auxiliar altitude, na estimativa da distribuição espacial da precipitação anual média no Estado de São Paulo. A estatística quadrado médio do erro (QME) foi usada em dois conjuntos de observações de precipitação anual média (1957 a 1997): o completo, com 1.027 observações, e o reduzido, com 445. Bolsões de precipitação foram perfeitamente definidos nos mapas de variabilidade espacial que utilizaram o conjunto completo de dados, e indicaram a existência de possíveis microclimas. O interpolador geoestatístico de krigagem ordinária apresentou desempenho 82 vezes mais preciso que o interpolador do inverso do quadrado da distância, quando o QME foi usado como critério de comparação...
Tipo: Artigo em periódico indexado (ALICE) Palavras-chave: Cokrigagem ordinária; Geoestatística; Krigagem ordinária; Métodos de interpolação; Microclima; Risco climático; Geostatistics; Kriging; Microclimate.
Ano: 2012 URL: http://www.alice.cnptia.embrapa.br/handle/doc/940569
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Modelación de la distribución espacial de la precipitación en el valle de la Ciudad de México usando técnicas geoestadísticas Colegio de Postgraduados
Méndez Venegas, Javier.
La mayor parte de la precipitación en la Ciudad de México es producida por tormentas convectivas, caracterizadas por una alta variabilidad espacial, lo cual implica un alto grado de complejidad en la modelación de su comportamiento. La precipitación es uno de los factores principales del ciclo hidrológico y el conocimiento de su distribución espacial es fundamental para la predicción de otras variables ambientales íntimamente relacionadas como son: el escurrimiento, las inundaciones, la recarga de los acuíferos, etc. En la presente tesis se propone la aplicación de técnicas geoestadísticas para modelar la distribución espacial de la precipitación en el caso de tormentas convectivas. Con este fin se aplican los procedimientos geoestadísticos de estimación...
Tipo: Tesis Palavras-chave: Geoestadística; Distribución espacial de la precipitación; Kriging; Cokriging; Modelo de corregionalización lineal; Simulación Secuencial Gaussiana; Maestría; Estadística; Geostatistics; Rainfall spatial distribution; Kriging; Cokriging; Linear coregionalization model; Sequential Gaussian Simulation.
Ano: 2008 URL: http://hdl.handle.net/10521/1640
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Rainfall erosivity in the Upper Paraguai River Basin, Brazil. Repositório Alice
GALDINO, S.; GREGO, C. R.; SILVA, J. dos S. V. da.
Mapping rainfall erosivity is a practical and indispensable tool for land use planning at regional scale, like large river basins. The objective of this study was to evaluate the spatial distribution of the annual erosive potential of rainfall for the Upper Paraguai Basin (BAP) in Brazil. For this, 125 pluviometric stations located in BAP and its surroundings were analyzed. The rainfall erosivity was estimated for each station using the Modified Fournier Index. For the spatial distribution of the erosive potential, the values for erosivity in each station were interpolated using the kriging method. Annual erosivity at BAP ranged from 5,105 to 9,169, with an average of 6,800 MJ mm ha-1 h-1. Erosivity was classified as moderate to strong in 69% of BAP and in...
Tipo: Artigo em periódico indexado (ALICE) Palavras-chave: Geotecnologia; Krigagem; Perda de solo; Regime pluviométrico; Pantanal; Erosividade das chuvas; Kriging; Geotechnology; Soil loss; Rain distribution.
Ano: 2015 URL: http://www.alice.cnptia.embrapa.br/handle/doc/1035884
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Rainfall erosivity in the upper Paraguai river basin, Brazil. Repositório Alice
GALDINO, S.; GREGO, C. R.; SILVA, J. dos S. V. da.
bitstream/item/175086/1/4611.pdf
Tipo: Artigo em periódico indexado (ALICE) Palavras-chave: Geotechnology; Rain distribution; Soil loss; Pantanal; Kriging.
Ano: 2015 URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1028812
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Regional Objective Analysis for Merging High-Resolution MERIS, MODIS/Aqua, and SeaWiFS Chlorophyll-a Data From 1998 to 2008 on the European Atlantic Shelf ArchiMer
Saulquin, Bertrand; Gohin, Francis; Garrello, Rene.
In this paper, we define the method that is used to merge high-resolution multisensor chlorophyll-a (chl-a) data on the Ireland-Biscay-Iberia Regional Ocean Observing System area from 1998 to the present at a resolution of 1.1 km. The method is based on geostatistics and is known as kriging. The merged variable is the daily anomaly of chl-a, with the anomaly being defined as the difference between the daily image and the mean historical field for the considered day. For each day, the continuous anomaly image is generated using the kriging method, and the mean historical field is then added to obtain the cloudless field of chl-a. The initial satellite chl-a data set used in the merging procedure is derived from the daily level-2 water leaving radiances of...
Tipo: Text Palavras-chave: Chlorophyll-a (chl-a); Kriging; Optimal interpolation; Remote sensing.
Ano: 2011 URL: http://archimer.ifremer.fr/doc/00029/14063/11369.pdf
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Regional objective analysis for merging MERIS, MODIS/Aqua and SeaWiFS Chlorophyll-a data from 1998 to 2008 on the European Atlantic Shelf at a resolution of 1.1Km. ArchiMer
Saulquin, Bertrand; Gohin, Francis; Garello, Rene.
In this paper we define the method used to merge high resolution multi-sensor chlorophyll-a data on the Ireland-Biscay-Iberia Regional Ocean Observing System (IBI-ROOS) area at a resolution of 0.015 degrees. The method is based on geostatistics and is known as kriging. The merged variable is the anomaly of chlorophyll-a, the anomaly being defined for a day as the difference between the daily image and the mean historical field for that day. The used chlorophyll-a dataset is derived from the daily level-2 water leaving radiances of the Sea-viewing Wide Field of View Sensor (SeaWiFS) of the Orbview platform, the Moderate Resolution Imaging Spectroradiometer (MODIS) of the Aqua platform and the Medium Resolution Imaging Spectrometer Instrument (MERIS) of the...
Tipo: Text Palavras-chave: Remote sensing; Chlorophyll-a; Optimal interpolation; Kriging.
Ano: 2009 URL: http://archimer.ifremer.fr/doc/00014/12536/9568.pdf
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Spatial and temporal interaction between sediment and microphytobenthos in a temperate estuarine macro-intertidal bay ArchiMer
Orvain, Francis; Lefebvre, Sebastien; Montepini, J.; Sebire, M.; Gangnery, Aline; Sylvand, B..
Intertidal flats of the estuarine macro-intertidal Baie des Veys (France) were investigated to identify spatial features of sediment and microphytobenthos (MPB) in April 2003. Gradients occurred within the domain, and patches were identified close to vegetated areas or within the oyster-farming areas where calm physical conditions and biodeposition altered the sediment and MPB landscapes. Spatial patterns of chl a content were explained primarily by the influence of sediment features, while bed elevation and compaction brought only minor insights into MPB distribution regulation. The smaller size of MPB patches compared to silt patches revealed the interplay between physical structure defining the sediment landscape, the biotic patches that they contain,...
Tipo: Text Palavras-chave: Benthic diatoms; Benthos; Coastal ecosystems; Intertidal flats; Baie des Veys; Normandie; Spatial pattern; Geostatistics; Kriging.
Ano: 2012 URL: http://archimer.ifremer.fr/doc/00088/19945/17598.pdf
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Spatio-temporal modeling of data imputation for daily rainfall series in homogeneous zones. Repositório Alice
CARVALHO, J. R. P. de; NAKAI, A. M.; MONTEIRO, J. E. B. A..
Spatio-temporal modelling is an area of increasing importance in which models and methods have often been developed to deal with specific applications. In this study, a spatio-temporal model was used to estimate daily rainfall data. Rainfall records from several weather stations, obtained from the Agritempo system for two climatic homogeneous zones, were used. Rainfall values obtained for two fixed dates (January 1 and May 1, 2012) using the spatio-temporal model were compared with the geostatisticals techniques of ordinary kriging and ordinary cokriging with altitude as auxiliary variable. The spatio-temporal model was more than 17% better at producing estimates of daily precipitation compared to kriging and cokriging in the first zone and more than 18%...
Tipo: Artigo em periódico indexado (ALICE) Palavras-chave: Modelos espaço-temporal; Dados de precipitação; Krigagem ordinária; Cokrigagem ordinária; Zonas homogêneas; Sistema Agritempo; Spatio-temporal model; Rainfall data; Ordinary kriging; Ordinary cokriging; Homogeneous zones; Models; Meteorological data; Kriging.
Ano: 2016 URL: http://www.alice.cnptia.embrapa.br/handle/doc/1048254
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Spatio-temporal patterns in demersal elasmobranchs from trawl surveys in the eastern English Channel (1988-2008) ArchiMer
Martin, Corinne; Vaz, Sandrine; Ellis, J. R.; Coppin, Franck; Le Roy, Didier; Carpentier, Andre.
Elasmobranchs have life-history characteristics that make them more vulnerable to fishing than many teleost fish. As commercial landings data are usually not sufficient for the monitoring and assessment of elasmobranchs, fisheries-independent data, geostatistics and Geographic Information Systems were used to investigate the spatio-temporal patterns of sharks (6 species), skates (9 species) and stingray in the eastern English Channel. Temporal trends in relative abundance and distributions of total-length frequencies were investigated using data collected over 21 yr from an annual survey using a Grande Ouverture Verticale (GOV) trawl. Temporal trends in relative abundance were examined qualitatively in relation to the reported conservation status for the...
Tipo: Text Palavras-chave: Elasmobranchii; Chondrichthyes; Kriging; GIS; Conservation; Sex ratio; Catchability; Channel Ground Fish Survey; CGFS.
Ano: 2010 URL: http://archimer.ifremer.fr/doc/00019/13029/10160.pdf
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