Characterization of spatial variability of the need of limestone for the application at a varied rate in an agricultural trade area

Abstract

Outside the ideal range of pH, the cultures are limited in terms of the availability of nutrients, so the setting of the limestone is linked directly to the production yield, in which the application is usually performed based on an average value of the Need for Limestone (NL). The work aims to build the map of NL, using the tools of Precision Agriculture (PA) and by the conventional methodology, then performing a comparison between the methods of application of NL used, giving the benefits of the varied rate application. 59 samples were collected through a sampling grid, within the experimental area of 82.67 ha. With the use of Geostatistics it was possible to determine the spatial variability of NL in the study area, with a moderate degree of spatial dependence between the sampled points, it was possible to build a thematic map of NL. By comparing the amount of lime to be applied according to the thematic map with the conventional method of application from the average of the NL, the amount of lime applied in varied rate decreased in the order of 73%, boasting with it, greater environmental benefits to the soil and also financial savings in the amount of correction.