Comparative analysis of soil-sampling methods used in precision agriculture

The aim of this study was to compare three different soil-sampling methods used in Precision Agriculture and their environmental impact on agricultural production. The sampling methods used were: Zone management by elevation, grid sampling (GS) and sampling oriented by apparent soil electrical conductivity (OS). Three different fields were tested. When the recommendations were compared, a significant difference among the suggested doses was observed. This indicated the need to improve the soilsampling techniques, since there were doubts about input deficits or overdoses, regardless of the technology studied. The GS method was the most environmentally viable alternative for phosphorus (P) compared to other methods and the OS presented as the better option for potassium (K) and nitrogen (N). However, the use of soil sensors appeared to be a viable technology that needs further improvement in order to improve productivity and, hence, economic and environmental benefits.