Validação de zonas de manejo a partir de atributos da fertilidade do solo

Abstract

Sorghum (Sorghum bicolor L. Moench) is a specie belonging to the Poaceae family, which has been gaining prominence due to its easy adaptation to different regions and its ability to achieve high yields. Due to its greater drought resistance, it is also being widely used as an alternative to corn in the second crop. With the growing global population and the need to feed all these people, researchers are seeking ways to increase crop productivity through technology. One of these technologies that is adding value to productivity enhancement is precision agriculture (PA), which encompasses a set of tools, including software, aimed at reducing losses and maximizing gains.One of the strategies used in precision agriculture is management zones (MZ), a technique that subdivides the field into sub-regions according to their productive potential in order to achieve greater accuracy and understanding of the determinants of spatial variability. Soil fertility is an attribute influenced by these management zones, as nutrient availability varies among zones, and this fertility is of paramount importance to productivity. The present study was conducted at Fazenda Capim Branco, located in the municipality of Uberlândia, state of Minas Gerais, Brazil, in an experimental area of 25 hectares where grain sorghum was cultivated. The experimental area was divided into three management zones, which were defined based on the generation of a large sample of 50 points. The following attributes were taken into consideration to divide the three management zones: area altitude, NDVI (Normalized Difference Vegetation Index), soil texture, electrical conductivity, and penetration resistance. Soil samples were collected within this area at depths of 0-20 cm and 20-40 cm, which were later taken to the soil analysis laboratory at UFU (Federal University of Uberlândia) in order to validate the management zones based on soil fertility. From the soil analysis, it was observed that there was a difference in fertility among the three management zones, with the zone of medium productive potential showing the highest fertility. Therefore, it was not possible to validate the definition of management zones based on soil fertility attributes. For this area, the presence of compaction, as observed in previous studies, prevented the high-potential zone from being considered as medium-potential.