2003, Las Vegas, NV July 27-30, 2003 · 2003 · 37 citations · 0 references
AgricultureEarth SciencesSoil SciencesRemote SensingSoil Organic MatterSoil ScienceField Soil ObservationInfrared SpectroscopySoil Carbon SensingSoil Nitrogen SensingSoil Organic Matter SensingSoil Sensor CalibrationCalibration ModelsIntensive SamplingPrincipal Component RegressionReflectanceReflectance SpectroscopySoil Organic CarbonSpectral Reflectance ModelingSpectral Reflectance Properties
Laboratory based near infrared spectroscopy (NIRS) has demonstrated good predictivecapability for many important soil constituents. Less is known about the feasibility of performing thespectroscopic measurements in a field setting. This paper presents some results of an initial fieldtest of a mobilized in-situ NIRS device. The results demonstrate good pass-to-pass repeatability andmeaningful qualitative images. Locally weighted principal component regression was used todevelop calibration models relating the reflectance data to levels of soil organic carbon, nitrogen,moisture and pH. The calibrations were used to create constituent maps for a field in central Iowaand compared to images derived from intensive sampling and laboratory analysis.