Variabilidade dos atributos químicos do solo em função da profundidade de amostragem em sistema plantio direto

Abstract

The need to improve the representativeness of soil sampling is essential for proper area management. Therefore, the project aimed to evaluate the variability of soil chemical attributes as a function of sampling depth in four areas managed under no-till systems located in the municipality of Cerro Largo, RS, Brazil. Soil samples were collected at three depths: 0-10 cm, 10-20 cm, and 0-20 cm, analyzing the main nutrients and their availability classes, as well as soil acidity indicators. The results showed higher concentrations of phosphorus, potassium, calcium, and magnesium in the 0-10 cm surface layer compared to the 10-20 cm and 0-20 cm layers, as well as lower pH values in the 10-20 cm layer, highlighting the need for stratification. Using the 0-20 cm layer for liming and fertilization recommendations resulted in overestimation of application rates when compared to the 0-10 cm layer. The averages of nutritional and acidity attributes between the stratified layers of 0-10 cm and 10-20 cm did not differ significantly compared to the 0-20 cm layer.