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| Souza, Gustavo Soares; UFES; Lima, Julião Soares de Souza; UFES; Silva, Samuel de Assis; UFES; Oliveira, Rone Batista de; UNESP. |
| Estudos mostram a importância de se conhecer a variabilidade dos atributos do solo para o manejo mais eficiente. O objetivo deste trabalho foi analisar a variabilidade espacial dos atributos químicos de um Argissolo Vermelho-Amarelo, cultivado com pastagem de Brachiaria decumbens, em Alegre – Espírito Santo. Amostras de solo foram coletadas na profundidade de 0-0,2 m, nos pontos de cruzamento de uma malha com intervalos regulares de 10 m, perfazendo o total de 64 pontos. Os dados foram submetidos à analise estatística descritiva, geoestatística e interpolação por krigagem ordinária. Os valores dos coeficientes de variação apresentaram-se baixos para pH, altos para Al e m% e médios para os demais atributos. Os atributos pH, P, H+Al e m% apresentaram forte... |
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Palavras-chave: 5.01.00.00-9 Agronomia dependência espacial; Geoestatística krigagem. spatial dependence; Geostatistics; Kriging. |
| Ano: 2008 |
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/5322 |
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| Neves,Débora Andréia; Lemos,Fábio; González,Antonio Paz; Vieira,Sidney Rosa; Siqueira,Glécio Machado. |
| Protecting natural mosaics as forest reserves poses a challenge, because if they hold significant high levels of biodiversity, they may function as key seed sources for regenerating ecosystems and adjacent reforested areas. Currently, there is lack of information about the spatial organization of native species in core forest fragments remaining between reforested fields. Biodiversity as measured by species and number of individuals was assessed in two forest reserve zones located within reforestations of Eucalyptus sp and Pinus sp in Agudos, São Paulo, Brazil. The main objective was to compare the state of biodiversity within two natural areas with contrasting disturbance levels; a second objective was to investigate recognisable patterns of species and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Nugget effect; Kriging; Semiovariograms. |
| Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052010000500014 |
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| Machado,Roriz Luciano; Ceddia,Marcos Bacis; Carvalho,Daniel Fonseca de; Cruz,Eleandro Silva da; Francelino,Marcio Rocha. |
| Knowledge of maximum daily rain and its return period in a region is an important tool to soil conservation, hydraulic engineering and preservation of road projects. The objective of this work was to evaluate the spatial variability of maximum annual daily rain considering different return periods, at the Rio de Janeiro State. The data set was composed by historical series of 119 rain gauges, for 36 years of observation. The return periods, estimated by Gumbel distribution, were 2, 5, 10, 25, 50 and 100 years. The spatial variability of the return periods was evaluated by semivariograms. All the return periods presented spatial dependence, with exponential and spherical model fitted to the experimental semivariograms. The parameters of the fitted... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Runoff; Extreme rainfall; Geostatistics; Kriging. |
| Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052010000500009 |
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| 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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| 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 |
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| Morales,Luis Alberto; Paz-Ferreiro,Jorge; Vieira,Sidney Rosa; Vázquez,Eva Vidal. |
| The aim of this study was to describe the effect of lime additions on the spatial variability of pH and Eh in a typic Plintacualf cultivated with rice, in Corrientes, Argentina. The 5.1 ha field was divided in three sub plots at which dolomitic lime additions were made at the rates zero, 625 kg ha-1 and 1250 kg ha-1. The soil was sampled at three stages: before sowing thus in aerobic conditions, and then two more times in anaerobiosis. Ninety-six samples per sub plot were taken on each of the three sampling stages on a grid of 11.9 x 20 m. Soil pH and Eh were measured by routine methods. The pH values increased, whereas Eh values decreased, following flooding. The coefficients of variation for pH was rather low during all the three studied periods.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Semivariogram; Flooded field; Liming; Kriging. |
| Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052010000500008 |
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| 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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| Aquino,Regimeire Freitas; Silva,Marx Leandro Naves; Freitas,Diego Antonio França de; Curi,Nilton; Mello,Carlos Rogério de; Avanzi,Junior Cesar. |
| Rainfall erosivity and its spatial variability were studied for 54 pluviometric stations in Southern Minas Gerais State (48º00' - 44º00'W; 23º50' - 20º00'S), aiming to plan the land-use strategies. Therefore, erosivity factor was determined for the pluviometric stations, using long-term rainfall data sets obtained along with the Brazilian National Water Agency- ANA, which varied from 15 to 40 years. The monthly and annual erosivity indexes were generated using Fournier equation for Lavras, MG and the spatial distribution of rainfall erosivity was studied on the basis of geostatistical approaches considering only the distance which separates them, developing the isotropic experimental semivariogram. The semivariogram adjustment was done based on the... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Erosive potential; Soil sustainability; Kriging. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542012000500006 |
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| Morais,Vinícus Augusto; Mello,José Marcio de; Mello,Carlos Rogério de; Silva,Carlos Alberto; Scolforo,José Roberto Soares. |
| ABSTRACT Litter corresponds to the layer of decomposing dead organic matter present on the soil surface. This layer is very important for nutrient cycling and contributes with organic matter accumulation in the soil, besides the carbon stock. The objective herein was to quantify the carbon biomass, both content and stock, and map the litter C-stock in the Cerrado biome, which is formed by Savanna Grassland (SG), Cerrado Stricto Sensu (CE) and Forest Savanna (FS), in Minas Gerais state, southeastern Brazil. The data were collected in 26 fragments in Minas Gerais state, totaling 210 sampling locations. A variographic study was conducted and, for mapping, the ordinary kriging method was used for delimitation of homogeneous zones. It was possible to detect... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Climate change; Kriging; Mapping procedures; Accumulated biomass.. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542017000500580 |
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| Ponciano,Patrícia F.; Yanagi Junior,Tadayuki; Ferraz,Gabriel A. E S.; Scalon,João D.; Schiassi,Leonardo. |
| The air dry-bulb temperature (t db),as well as the black globe humidity index (BGHI), exert great influence on the development of broiler chickens during their heating phase. Therefore, the aim of this study was to analyze the structure and the magnitude of the t db and BGHI spatial variability, using geostatistics tools such as semivariogram analysis and also producing kriging maps. The experiment was conducted in the west mesoregion of the states of Minas Gerais in 2010, in a commercial broiler house with heating system consisting of two furnaces that heat the air indirectly, in the firsts 14 days of the birds' life. The data were registered at intervals of five minutes in the period from 8 a.m. to 10 a.m. The variables were evaluated by variograms... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Broiler chickens; Kriging; Chick; Semivariogram; Thermal stress. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162013000300001 |
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| 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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| Registros recuperados: 45 | |
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