Predicción de propiedades del suelo de importancia agronómica por espectroscopia de reflectancia de infrarrojo cercano* Predicting soil traits of agronomic importance by of near infrared reflectance spectroscop

The growing interest in information about soil traits quickly, accurately and cheaply has resulted in an increase in the use of near-infrared spectroscopy (NIRS) for this application. The main objective of this study was to evaluate the ability of NIRS to predict soil traits on 12 agronomically important in northern Mexico. Samples were collected from agricultural plots of two regions designated as site 1, Baja California (BC, n= 128) and site 2, Chihuahua (n= 143). Infrared spectra were obtained from two sizes of soil particles: thick ( 1.4) for pH, EC, CEC, K content of sand, clay and silt in the group of cross-validation samples for at least one site was obtained. The results were consistent with those obtained in the group of independent validation, except for pH and silt which had a RPD <1.4. The traits without predictability by NIRS were N-NO3, N-NH4, P, total carbonates (CO3) and organic matter. An important advantage of NIRS for soil analysis is that from a spectrum can be determined many traits. One limitation of this study was the number of samples used for independent validation, which consisted of 10% of total samples.