An Investigation into the Effects of Soil Slope and Rainfall Intensity on Solute Transport Using Laboratory Experiments and HYDRUS-2D Model

Soil is not only a medium for plant growth but also a transmitter of contaminants to atmosphere¡ surface water and ground water. Therefore¡ studying the movement of substances in soil is important. In this study¡ the effects of soil slope and rainfall intensity on solute transport in soil were investigated under laboratory conditions. The experiments were conducted in two sloping and not-sloping soil bulk and included injection of a conservative solute (NaCl) with two different intensities. The results showed that the soil slope increases the solute transport in the lateral direction¡ and the increase of injection intensity accelerates the solute movement towards the depths and increases the peak concentration. Solute movement was well simulated using Hydrus-2D model with the coefficient of determination (R2) between 0.848-0.907¡ the Nash– Sutcliffe efficiency coefficient (EF) between 0.805-0.907 and the low values of the root mean square error (RMSE).