Analysis of visible and near infrared spectral reflectance for assessing metals in soil.

摘要: Visible and near infrared reflectance (VNIR; 350–2500 nm) spectroscopy has greatly been used in soils, especially for studying variability spectrally active soil components (e.g., organic carbon, clays, Fe/Al oxides) based on their diagnostic spectral features. In recent years, this technique also applied to assess metallic ions. research, the feasibility of VNIR determination metals was investigated with two data sets: (i) artificially metal-spiked (ii) situ metal-contaminated soils. Results showed that spectra neither soils Cd, As, Pb even at higher concentrations 20, 900, 1200 mg kg−1, respectively, nor (with 30 mg 3019 mg 5725 mg Pb kg−1 soil) any recognized absorption peaks correspond metal concentrations. We observed variations intensity only, showing across entire spectrum strongly lower less A significant correlation found between surface metals’ continuum removed spectra, while were significantly associated matter total Fe. partial least square regression cross-validation approach produced an acceptable prediction (R 2 = 0.58–0.94) both sets, However, high values root mean error ruled out practical application achieved models.