01892naa a2200253 a 450000100080000000500110000800800410001902400270006010000140008724501480010126000090024952011230025865000090138165000110139065300300140165300080143165300190143965300070145865300290146565300230149465300190151770000180153677300840155410602102019-09-23       2002    bl uuuu     u00u1 u    #d7 a10.1255/jnirs.3382DOI1 aMORON, A.  aApplication of near infrared reflectance spectroscopy for the analysis of organic C, total N and pH in soils of Uruguay.h[electronic resource]  c2002  aNear infrared (NIR) reflectance spectroscopy was used to analyse samples (n = 332) from different soils from Uruguay (South America) for organic carbon (OC), total nitrogen (N) and pH. One set (n = 200) of samples randomly selected was used to develop the NIR calibrations while the remaining (n = 132) samples were used as the validation set. The samples were scanned in a small circular cup in reflectance mode (400?2500 nm), using a Foss NIRSystems 6500 (Silver Spring, MD, USA). Modified partial least squares (MPLS) was used to produce the calibration models and cross-validation was used to avoid collinearity effects among variables. Three mathematical treatments and four scatter corrections were also applied. The calibration coefficient of determination (R2 CAL) and the standard error in cross-validation (SECV) were 0.94 (SECV: 1.9) for OC; 0.91 (SECV: 0.19) for total N in g kg?1 and 0.93 (SECV:0.18) for pH, respectively. The simple correlation coefficient of validation (rVAL) and the standard errors of prediction (SEP) were 0.74 and 5; 0.73 and 0.4; 0.84 and 0.28 for OC, total N and pH, respectively.  aNIRS  aSUELOS  aESPECTROSCOPIA INFRARROJA  aNIR  aORGANIC CARBON  aPH  aREFLECTANCE SPECTROSCOPY  aSUELOS DEL URUGUAY  aTOTAL NITROGEN1 aCOZZOLINO, D.  tJournal of Near Infrared Spectroscopy, 2002, Volume 10, Issue 3, Pages 215-221.