Summary: | Techniques such as mid-infrared (MIR) spectroscopy can be used to identify the classes and properties of soils with high precision. In the present study, 312 soil samples of different orders, which were representative of Colombian agricultural zones, were studied, including Inceptisols and Vertisols of the Sinú valley (Córdoba), Andisols of the Eastern Andes Mountain range (Cundinamarca), and Oxisols of the Eastern plains of Colombia (Meta), with the aim of evaluating the ability of mid-infrared spectroscopy to estimate soil properties such as organic carbon, Ca, Mg, Na, K, P, Al, and pH. The results obtained through the analysis of the curves led to the observation that the greatest number of properties are reflected in the spectral region between 400 and 850 cm-1. In the analysis through infrared MIR spectroscopy, the spectrum for the three soils were manifested in similar spectral regions, but with different levels of reflectance, mainly due to the content of MO. In the descriptive analysis, the observed values showed a behavior similar to the values predicted with the models for those properties with representative spectral models. The majority of the properties did not show a normal distribution and the coefficients of variation were very high.
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