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Spatial dependency and correlation of properties of soil cultivated with oil palm, Elaeis guineensis, in agroforestry systems in the eastern Brazilian Amazon Acta Amazonica
SILVA,Camila Santos da; MENDONÇA,Bruno Araujo Furtado de; PEREIRA,Marcos Gervasio; ARAÚJO,Emanuel José Gomes de; CASTELLANI,Débora Christina.
ABSTRACT Geostatistics is a tool that can be used to produce maps with the distribution of nutrients essential for the development of plants. Therefore, the present study aimed to analyze the spatial variation in chemical attributes of soils under oil palm cultivation in agroforestry systems in the eastern Brazilian Amazon, and their spatial dependence pattern. Sixty spatially standardized and georeferenced soil samples were collected at each of three sampling sites (DU1, DU2, and DU3) at 0-20 cm depth. Evaluated soil chemical attributes were pH, Al3+, H+Al, K+, Ca2+, Mg2+, cation exchange capacity (CEC), P, and organic matter (OM). The spatial dependence of these variables was evaluated with a semivariogram analysis, adjusting three theoretical models...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Cokriging; Ordinary kriging; Semivariogram; Soil properties.
Ano: 2018 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0044-59672018000400280
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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
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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
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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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Spatial estimation of foliar phosphorus in different species of the genus Coffea based on soil properties Rev. Bras. Ciênc. Solo
Silva,Samuel de Assis; Lima,Julião Soares de Souza.
Information underlying analyses of coffee fertilization systems should consider both the soil and the nutritional status of plants. This study investigated the spatial relationship between phosphorus (P) levels in coffee plant tissues and soil chemical and physical properties. The study was performed using two arabica and one canephora coffee variety. Sampling grids were established in the areas, and the points georeferenced. The assessed properties of the soil were levels of available phosphorus (P-Mehlich), remaining phosphorus (P-rem) and particle size, and of the plant tissue, phosphorus levels (foliar P). The data were subjected to descriptive statistical analysis, correlation analysis, cluster analysis, and probability tests. Geostatistical and trend...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Coffee; Remaining P; Cokriging; Geostatistics.
Ano: 2014 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832014000500009
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Spatial variability of soil CO2 emission in a sugarcane area characterized by secondary information Scientia Agricola
Teixeira,Daniel De Bortoli; Bicalho,Elton da Silva; Panosso,Alan Rodrigo; Cerri,Carlos Eduardo Pellegrino; Pereira,Gener Tadeu; Scala Júnior,Newton La.
Soil CO2 emission (FCO2) is governed by the inherent properties of the soil, such as bulk density (BD). Mapping of FCO2 allows the evaluation and identification of areas with different accumulation potential of carbon. However, FCO2 mapping over larger areas is not feasible due to the period required for evaluation. This study aimed to assess the quality of FCO2 spatial estimates using values of BD as secondary information. FCO2 and BD were evaluated on a regular sampling grid of 60 m × 60 m comprising 141 points, which was established on a sugarcane area. Four scenarios were defined according to the proportion of the number of sampling points of FCO2 to those of BD. For these scenarios, 67 (F67), 87 (F87), 107 (F107) and 127 (F127) FCO2 sampling points...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Geostatistics; Cokriging; Ordinary kriging; Cross-variogram.
Ano: 2013 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162013000300008
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