Application of Near-Infrared Reflectance Spectroscopy in the Measurement of Carbon, Nitrogen, and Phosphorus in Seston from Oligotrophic Lakes

The application of near-infrared spectroscopy (NIRS), widely used in the agricultural, food, and pharmaceutical industries, is extended to the measurement of C, N, and P in seston from oligotrophic lakes at the Experimental Lakes Area, northwestern Ontario. Seston from 150-mL aliquots of lake water from several depths in two lakes on one mid-June sampling date was collected on Whatman GF/C filters and measured first by NIRS then analyzed by standard wet chemistry methods. Correlation between chemically measured and NIRS-predicted values gave coefficients of determination between 0.913 and 0.982. The rapid, low-cost, nonchemical, nondestructive, efficient analysis of C, N, and P in seston by NIRS is feasible.