Avaliação das curvas espectrais de dois solos em função da variação de atributos físicos e químicos na região de Jaciara-MT

Abstract

Spectroscopy as a tool in the characterization of soil variability and prediction of its components, has been used increasingly in precision agriculture. New sensors based on the technique of visible and near infrared spectroscopy has been used to characterize soil variability. This paper aimed to evaluate spectral curves obtained by a sensor used in two soils, due to the variation of physical and chemical attributes, using a spectrophotometer sensor VIS-NIR, called Veris Spectophotometer. Samples of soil was collected in two areas with sandy texture and clayey texture. Then it was determined the moisture, phosphorus, potassium, clay and organic matter content. With the use of sensor, spectral readings were taken in field and on bench, with subsequent elaboration of spectral curves. In sandy soil, the increase in clay content and moisture resulted in an increase of absorbance. Absorbance has decreased with phosphorus content increasing, both in field and bench readings. With potassium increasing, absorbance decreased in field readings and increased in bench readings. Besides, absorbance has increased with the organic matter content increasing, in bench readings, and with soil moisture increasing, in field readings. In clay soil, it was observed a decrease in absorbance with organic matter content increasing and soil moisture increasing, in field readings.