摘要:Abstract. Application of crop residues (mulch) over the soil surface is acommon practice to control soil erosion and promote infiltration. Thislaboratory study aimed at investigating the effect of different rice strawmulch sizes on runoff and sediment transport. The experimental runs wereconducted using a soil flume of adjustable slope and a rainfall simulator,considering bare soil and three different soil covers: 1, 2 and 5t ha−1application rates, for three sizes of rice straw mulch (10, 30and 200mm). The experimental results showed that for the same mulchapplication rate (by weight), the smaller mulch sizes (i.e. high surfacecoverage percentage) presented less soil loss. For example, 90% soil lossreduction was achieved for smaller sizes of rice straw mulch and 80% forthe bigger size. The results of this study are an important contribution tothe understanding of the soil loss process in small basins and to thedefinition of relevant soil conservation measures, at the plot/field scale.