Effect of Rice Straw Mulch on Surface Runoff and Soil Loss in Agricultural Land under Simulated Rainfall

Abstract

Installation of mulch on agricultural land, besides reducing weed growth, can also protect the soil surface from rain and erosion. This study aims to determine the effectiveness of rice straw mulch in reducing surface runoff and soil loss before entering the river. The experimental soil materials were similar to those in Sumber Brantas village, Bumiaji Sub-District, Batu. Runoff modelling utilized the Armfield S12 Rainfall Simulator - Advanced Environmental Hydrology System, with rainfall of 1 and 1.7 l/min. Land with rice straw mulch was compared to land without mulch. The land slope was adjusted to study area conditions, with mild (9%) and steep (15%) slopes. The three-Way ANOVA method was utilized for statistical analysis. In all the experimental runs, it was found that straw mulch effectively reduced the sediment yields that could enter the river area by more than 50%. The results of ANOVA analysis on sediment yield also showed that the significance value of the interactions between slope, rain intensity, and mulch usage was 0 (p<0.05). These results show that the difference in variations in these three factors determines the sediment yield that occurs. In the future, comparing straw mulch with other materials to cover agricultural land should be conducted.