Figure 4
From: Retrieving zinc concentrations in topsoil with reflectance spectroscopy at Opencast Coal Mine sites
Correlation of determination (R2, P < 0.01) between Zn concentrations corrected by natural logarithmic transformation and spectral reflectance transformed by CR, FD, SG, SD, MSC, ABS, and SNV under six conditions of soil samples, including (a): lab-based processed, (b): lab-based unprocessed, (c): in-situ, (d): clean group (Zn ≤ 48.6 mg kg−1), (e): low pollution group (48.6 ≤ Zn ≤ 97.2 mg kg−1), and (f): moderate pollution group (97.2 ≤ Zn ≤ 145.8 mg kg−1). (Note: The spectral reflectance was measured after processing at the laboratory for the clean group, low pollution group, and moderate pollution group.)
