A rainfall simulation study of soil erodibility and available nutrient losses from two contrasting soils in China

Abstract

The relationship between soil erodibility and sediment-bound available nitrogen (AN) and available phosphorus (AP) losses were rarely mentioned in previous studies. The experiments were carried out using a soil flume and a rainfall simulator to evaluate the relationship. The impacts of rainfall intensity and slope on sediment-bound AN and AP losses and the relationship between soil erodibility and soil properties were also studied. Eight simulated rainfalls were applied on the flumes with different conditions (two rainfall intensities, two slopes) from two contrasting soil of China (Burozems and Cinnamon) with two replicates. The soil erodibility of Cinnamon is much higher than that of Burozems. The higher soil erodibility of the Cinnamon soil resulting in greater runoff, soil loss and sediment-bound AN and AP losses. The sediment yield rate significantly influenced the sediment-bound AN and AP losses. The soil erodibility also significantly influenced the sediment-bound AN and AP losses based on Principal Components Analysis (PCA) result. The results of PCA also showed that other soil properties (organic matter, bulk density and cation exchange capacity) were related to soil erodibility. Increasing rainfall intensity and slope resulted in increasing runoff, sediment and sediment-bound AN and AP losses for both soils. Our study showed a good evaluation with the role of soil erodibility related to sediment-bound AN and AP losses and other soil erosion parameters.