Spatial variability of the fertility attributes of Dystropheric Red Latosol under a no-tillage system

Authors

  • Flávio Dalchiavon Universidade Estadual de São Paulo
  • Morel Carvalho Universidade Estadual de São Paulo
  • Marcelo Andreotti Universidade Estadual de São Paulo
  • Rafael Montanari Universidade Estadual de Mato Grosso do Sul

Keywords:

Precision Agriculture, Soil fertility, Geostatistics, Kriging chart

Abstract

Knowledge of the spatial variability of soil fertility is very important, especially in precision agriculture. Thus during the 2009/2010 agricultural year, in the city of Selva (MS) in the Brazilian Cerrado, the objective was to analyse the spatial variability of the fertility attributes of a Dystropheric Red Latosol under a no-tillage system. A sampling grid was installed to collect soil samples, with 120 sampling points in an area of ​​3.0 ha and on an even slope of 0.055 m m-1. The available phosphorus content, organic matter content, values of pH (CaCl2), levels of K+, Ca+2, Mg+2, values ​​of base and aluminum saturation were all determined at depths of 0 to 0.10m and 0.10 to 0.20m. A classic descriptive analysis was carried out with the help of the SAS statistical software, and semivariograms were then modeled for all attributes, giving the respective cross-validations and kriging chartswith the GS+ 7.0 software. The largest variability, in the chemical attributes analysed by the coefficient of variation, occurred in the soil-depth layer of 0.10-0.20m. All studied chemical attributes showed spatial dependence, it being possible to map the study area. As they represent the spatial continuity of the semivariograms obtained in this study, the values ​​of the geostatistical ranges recommended for those attributes here studied, should be between 40.2 and 113.1 metres.

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Published

2012-03-23

Issue

Section

Soil Science