EFFECTS OF SUSPENDED PARTICLE-SIZE AND CONCENTRATION ON REFLECTANCE MEASUREMENTS

Laboratory based studies related to reflectance response of suspensions carrying five different soil types and particle sizes of varying concentrations indicate dependence of reflectance measurements on soil type characteristics, particle size, and concentration. Reflectance for any soil type and size increases with suspended sediment concentration and turbidity but decreases with increase in the modified secci depth of the suspension. Reflectance also increases with a decrease in particle sizes for any soil type. Models have been evolved for the prediction of suspended sediment concentration, turbidity, and modified secci depths from measured reflectance values for a given soil type and size, and also with due involvement of particle size in the predictive models. The predicted and observed values of suspended sediment concentration, turbidity, and modified secci depth, by the various evolved models, show good agreement.