Data/hora: 16/06/2024 00:41:48

Provedor de dados: | 70
País: | Brazil
Título: | REDUCTION OF SAMPLE SIZE IN THE ANALYSIS OF SPATIAL VARIABILITY OF NONSTATIONARY SOIL CHEMICAL ATTRIBUTES
Autores: | Maltauro,Tamara C.; Guedes,Luciana P. C.; Uribe-Opazo,Miguel A.
Data: | 2019-09-01
Ano: | 2019
Palavras-chave: | Fisher information matrix; Genetic algorithm; Geostatistics; Spatial dependence.
Resumo: | ABSTRACT In the study of spatial variability of soil attributes, it is essential to define a sampling plan with adequate sample size. This study aimed to evaluate, through simulated data, the influence of parameters of the geostatistical model and sampling configuration on the optimization process, and resize and reduce the sample size of a sampling configuration of a commercial area composed of 102 points. For this, an optimization process called genetic algorithm (GA) was used to optimize the efficiency of the geostatistical model estimation based on the Fisher information matrix. The simulated data evidenced that the variation of the nugget effect or practical range did not significantly alter the sample size. GA was efficient in reducing the sample size, determining for soil chemical attributes a sample size between 30 and 40 points (29.41 to 39.22% of the initial sampling grid). The presence of spatial dependence was observed for all soil chemical attributes in the two sampling configurations (initial and optimized). The optimized sampling configuration evidenced an increase in trend intensity in the north direction and a more efficient estimation of parameters of the linear spatial regression model.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162019000800056
Editor: | Associação Brasileira de Engenharia Agrícola
Relação: | 10.1590/1809-4430-eng.agric.v39nep56-65/2019
Formato: | text/html
Fonte: | Engenharia Agrícola  v.39 n.spe 2019
Fonte: | info:eu-repo/semantics/openAccess