Comparative application of optic scanner, rillmeter and paraffin methods in rill erosion measurement

Measuring soil erosion and sediment yield using different methods is necessary to achieve integrated and reliable information from amount of soil loss. In this regards, the application of new and up-to-date innovative methods is required and important to facilitate the measurements, which leads to increase the accuracy. However, there is no enough information for the efficiency assessment of innovative techniques. An optic scanner method therefore was used in the present study to measure soil particles detached/transported by splash/runoff. Then, the obtained results were compared with two traditional methods. Including rillmeter and paraffin, which were applied for the measurement of rill erosion in the laboratory. For this study, first a clay loam soil was poured in experimental plots with 30×40 cm dimensions and slope of 20%. The study plots were then exposed to sheet erosion under simulated rainfall intensity of 50 mm h-1 with duration of 20 minutes. In the next stage, two simulated rainfall intensities of 90 and 100 mm h-1 with duration of 20 and 80 minutes, were applied, respectively. The output runoff and sediment were collected and measured. Consequently, the results of optic scanner were compared with sediment measurements and also rillmeter and paraffin methods. Average soil erosion amount at the intensity of 90 mm h-1 with duration of 20 minutes based on optic scanner, rillmeter and paraffin were 283.30±79.73, 35.8±49.27, and 45.93±9.22 gr, whereas average soil erosion amount at the intensity of 100 mm h-1 with duration of 80 minutes were 377.94±274.22, 41.5±45.71, and 46.20±11.45 gr, respectively. According to the results, it was clear that the results of optic scanner was significantly different from other methods and overestimated soil erosion.