The potential for remote sensing of loess soils suspended in surface waters

The potential for detecting the concentration and type of soils suspended in surface water through remote sensing techniques was investigated by studying the spectral reflectance of two types of soils in suspension. In a large tank filled with 7510 liters of water, 20 levels of suspended sediment (soil) concentration (SSC), ranging from 50 to 1000 mg/l were prepared. A high resolution spectroradiometer was used to measure the reflectance at each SSC level. The reflectance spectra of two contrasting soils were distinct in the visible and near infrared (NIR) portions of the electromagnetic spectrum. The wavelength range between 580-690 nm (visible) was found to be optimal for indicating the type of soil, whereas, the wavelength range between 714-880 (NIR) was found to be appropriate for estimating the concentration of sediment suspended in surface waters