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Análise espacial da produtividade agrícola no Estado do Paraná: implicações para o seguro agrícola AgEcon
Ozaki, Vitor Augusto.
This paper analyses the spatial pattern of the agricultural yield data. Using the spatial statistics, it is possible to estimate some parameters of the semivariogram to study the problem of the systemic risk, which has great implications for the crop insurance program in Brazil. In particular, the “range” parameter was estimated. This parameter measures the distance, in which the spatial correlation tends to zero. For the empirical analysis, county yield data was used provided by IBGE, for soybean and corn, in the state of Paraná, through 1990 and 2002. The results showed that there is spatial dependence in every year analysed, going to zero in relatively long distances (in km).
Tipo: Journal Article Palavras-chave: Crop insurance; Systemic risk; Spatial correlation; Semivarioram.; Agribusiness; Q19.
Ano: 2008 URL: http://purl.umn.edu/61239
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Bovine landscape genetics in Brazil Scientia Agricola
Souza,Ana Clara Barbosa de; Egito,Andréa Alves do; Peripolli,Vanessa; McManus,Concepta Margaret.
ABSTRACT The aim of this study was to explore spatial genetic structure patterns in cattle breeds adapted to local conditions in Brazil. We georeferenced 876 animals of ten breeds raised in Brazil kept in the Genebank of Brazilian Agricultural Research Corporation (Embrapa) by sample locations using the QGIS 2.4.0 software. The Mantel tests, spatial autocorrelation, and Monmonier tests were performed. The distances for spatial correlation tests ranged from 5 to 15 classes. The results indicated genetic discontinuities in cattle breeds from the Midwest, South, and Southeast of the country. Correlation between genetic and geographic distance was low, but significant. The Monmonier Maximum Distance Algorithm indicated an initial subdivision of Curraleiro and...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Cattle; Genetic landscape shape; Georeference; Spatial correlation.
Ano: 2022 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162022000100403
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Impact of Capital Gains and Urban Pressure on Farmland Values: A Spatial Correlation Analysis AgEcon
Moss, Charles B.; Mishra, Ashok K.; Livanis, Grigorios T..
Farmland is a major component of wealth in the farm sector as well as wealth of farm households. This study contributes to our knowledge of variations in farmland prices by examining the extent to which farmland values are spatially correlated and to what extent that this spatial correlation can be explained by income to farmland.
Tipo: Conference Paper or Presentation Palavras-chave: Land values; Spatial correlation; Land Economics/Use.
Ano: 2007 URL: http://purl.umn.edu/9899
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Magnetic susceptibility for characterizing areas with different potentials for sugarcane production PAB
Siqueira,Diego Silva; Marques Júnior,José; Teixeira,Daniel De Bortoli; Matias,Sammy Sidney Rocha; Camargo,Livia Arantes; Pereira,Gener Tadeu.
Abstract The objective of this work was to evaluate the use of magnetic susceptibility for characterizing the spatial variability of soil attributes and identifying areas with different potentials for sugarcane (Saccharum spp.) production. Samples were collected at 110 points (1 per 7 ha) in the layers of 0.00-0.20 and 0.20-0.40 m, to determine the magnetic susceptibility and physical and chemical attributes of the soil. Fiber content, sucrose polarization (POL), and sugarcane yield were determined in 33 points. The spatial variability model for magnetic susceptibility was 63 and 22% more accurate in delimiting soil potential for sugarcane production than soil physical and chemical attributes at the 0.0-0.2 and 0.2-0.4-m layers, respectively. The spatial...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Detailed mapping; Geostatistics; Indirect quantification; Pedometrics; Scaled semivariogram; Spatial correlation.
Ano: 2016 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2016000901349
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Redundant variables and the quality of management zones REA
Ricardo,Sobjak; Souza,Eduardo G. de; Bazzi,Claudio L.; Uribe-Opazo,Miguel A.; Betzek,Nelson M..
ABSTRACT Precision agriculture (PA) allows farmers to identify and address variations in an agriculture field. Management zones (MZs) make PA more feasible and economical. The most important method for defining MZs is a fuzzy C-means algorithm, but selecting the variable for use as the input layer in the fuzzy process is problematic. BAZZI et al. (2013) used Moran’s bivariate spatial autocorrelation statistic to identify variables that are spatially correlated with yield while employing spatial autocorrelation. BAZZI et al. (2013) proposed that all redundant variables be eliminated and that the remaining variables would be considered appropriate on the MZ generation process. Thus, the objective of this work, a study case, was to test the hypothesis that...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Precision agriculture; Spatial correlation; Relative efficiency.
Ano: 2016 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162016000100078
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Spatial autocorrelation of ndvi and gvi indices derived from landsat/tm images for soybean crops in the western of the state of Paraná in 2004/2005 crop season REA
Dalposso,Gustavo H.; Uribe-Opazo,Miguel A.; Mercante,Erivelto; Lamparelli,Rubens A. C..
This research aims at studying spatial autocorrelation of Landsat/TM based on normalized difference vegetation index (NDVI) and green vegetation index (GVI) of soybean of the western region of the State of Paraná. The images were collected during the 2004/2005 crop season. The data were grouped into five vegetation index classes of equal amplitude, to create a temporal map of soybean within the crop cycle. Moran I and Local Indicators of Spatial Autocorrelation (LISA) indices were applied to study the spatial correlation at the global and local levels, respectively. According to these indices, it was possible to understand the municipality-based profiles of tillage as well as to identify different sowing periods, providing important information to...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Spatial statistics of areas; Spatial correlation; Vegetation index.
Ano: 2013 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162013000300009
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SPATIAL COMPETITION AND ETHANOL PLANT LOCATION DECISIONS AgEcon
Sarmiento, Camilo; Wilson, William W..
This article estimates factors that impact location decisions by new ethanol plants using logistic regression analysis and spatial correlation techniques. The results indicate that location decisions are impacted by the agricultural characteristics of a county, competition, and state-level subsidies. Spatial competition is particularly important. Existence of a competing ethanol plant reduces the likelihood of making a positive location decision and this impact decreases with distance. State-level subsidies are significant and a very important factor impacting ethanol location decisions.
Tipo: Conference Paper or Presentation Palavras-chave: Ethanol; Location decisions; Spatial correlation; Agribusiness.
Ano: 2008 URL: http://purl.umn.edu/6175
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Spatial distribution of Canola culture in the State of Paraná (Brazil) between the agricultural years of 2005 and 2009 Ciencia e Investigación Agraria
Costa Wrublack,Suzana; Prudente,Victor H.R.; Mercante,Erivelto; Machado Coelho,Sílvia R..
S.C. Wrublack, V.H.R. Prudente, E. Mercante, and S.R.M Coelho. 2013. Spatial distribution of Canola culture in the State of Paraná (Brazil) between the agricultural years of 2005 and 2009. Cien. Inv. Agr. 40(3): 513-521. There are a number of crops that are viable for small farms. To increase our knowledge of the occurrence of canola cultivation in the State of Paraná, the present study aimed to identify the areas sown with canola (ha) and to examine canola production (t) during the growing seasons of 2005 to 2009. The methodology involved a literature review and analysis of spatial data from the Secretaria da Agricultura e do Abastecimento do Paraná (SEAB/PR). We used the software ArcGis 9.3 for elaboration of thematic maps of variables as well as the...
Tipo: Journal article Palavras-chave: Spatial analysis; Spatial correlation; Statistic for areas; Vegetation cover.
Ano: 2013 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-16202013000300005
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Spatial relationships between soil attributes and corn yield in no-tillage system Rev. Bras. Ciênc. Solo
Rodrigues,Marcos Sales; Corá,José Eduardo; Fernandes,Carolina.
Soil properties play an important role in spatial variability of crop yield. However, a low spatial correlation has generally been observed between maps of crop yield and of soil properties. The objectives of the present investigation were to assess the spatial pattern variability of soil properties and of corn yield at the same sampling intensity, and evaluate its cause-and-effect relationships. The experimental site was structured in a grid of 100 referenced points, spaced at 10 m intervals along four parallel 250 m long rows spaced 4.5 m apart. Thus, points formed a rectangle containing four columns and 25 rows. Therefore, each sampling cell encompassed an area of 45 m² and consisted of five 10 m long crop rows, in which the referenced points...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Geostatistics; Precision agriculture; Soil sampling intensity; Spatial correlation; Zea mays.
Ano: 2012 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832012000200029
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Spatial statistics applied to soybean production data from Paraná State for 2003-04 to 2009-10 crop-years REA
Prudente,Victor H. R.; Souza,Carlos H. W. de; Mercante,Erivelto; Johann,Jerry A.; Uribe-Opazo,Miguel A..
In the current study, we performed a soybean production spatial distribution analysis in Paraná State. Seven crop-year data, from 2003-04 to 2009-10, obtained from the Paraná Department of Agriculture and Supply (SEAB) were used to develop a Boxmap for each crop-year, show soybean production throughout this time interval. Moran's index was used to measure spatial autocorrelation among municipalities at an aggregate level, while LISA index local correlation. For each index, different contiguity matrix and order were used and there was a significance level study. As a result, we have showed spatial relationship among cities regarding the production, which allowed the indication of high and low production clusters. Finally, identifying main soybean-producing...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Spatial correlation; Moran's Index; LISA index.
Ano: 2014 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162014000400015
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Uso de imagens de sensoriamento remoto para identificação de variabilidade espacial em Agricultura de Precisão. Repositório Alice
SPERANZA, E. A.; ANTUNES, J. F. G.; INAMASU, R. Y..
Resumo. A Agricultura de Precisão (AP) tem como principal objetivo aumentar o retorno econômico de uma lavoura, considerando o uso racional de insumos agrícolas a partir da identificação da variabilidade espacial dos atributos do solo e da cultura. Dentre esses atributos, aqueles que permitem a geração de mapas referentes a biomassa vegetal presente em alguns estágios de crescimento da lavoura, como o Índice de Vegetação por Diferença Normalizada (NDVI) que indica a presença e o vigor da vegetação, podem auxiliar de maneira significativa na identificação da variabilidade espacial da área de cultivo. Este trabalho descreve um experimento para verificação da correlação espacial entre imagens de sensoriamento remoto em diferentes resoluções espaciais, em uma...
Tipo: Anais e Proceedings de eventos Palavras-chave: Biomassa vegetal; Correlação espacial; Resolução espacial; Vegetal biomass; Spatial correlation; Spatial resolution; Sensoriamento Remoto; Agricultura de Precisão; Remote sensing; Precision agriculture; Normalized difference vegetation index.
Ano: 2018 URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1099230
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Valuing a Spatially Diverse Non-Market Good: The Benefits of Reduced Non-Point Source Pollution in Green Bay, WI AgEcon
Moore, Rebecca; Bishop, Richard C.; Provencher, Bill.
This article presents an empirical approach to correcting for spatial interactions in stated preference data when valuing large-scale, spatially variable environmental improvements. This approach is presented in the context of a contingent valuation study estimating the benefits of reduced non-point source pollution in Green Bay, Wisconsin. The significant spatial variation of water clarity conditions in this large water body was captured using satellite-derived GIS data. This article focuses on two significant challenges: first, ensuring respondents are adequately informed of how the proposed change will impact their individual utility stream; second, dealing with the spatial effects within the estimation model. The GIS water clarity data were used to...
Tipo: Conference Paper or Presentation Palavras-chave: Water quality; Non-point source pollution; Contingent valuation; Spatial correlation; Environmental Economics and Policy; Resource /Energy Economics and Policy.
Ano: 2007 URL: http://purl.umn.edu/9809
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