This study investigated the effects of soil particle size on the reflectance spectra of sandy soils using ultraviolet, visible, and near-infrared spectroscopy in sensing phosphorus (P) concentration. Pure sandy soil was graded into three particle sizes. Sieve sizes were 125, 250, and 600 m for fine, medium, and coarse, respectively. Phosphorus application rates for the soil samples were 0.0, 12...
