Importance of surface sealing in the erosion of some soils from a mediterranean climate

Poor aggregate stability and high erodibility of soils found in Mediterranean climates are often due to low organic matter content. The low organic matter content is sometimes compensated for by iron oxides that stabilize soil structure. Low water stability of aggregates often determines the propensity for soils to form surface crusts and seals (wet crusts). Seals reduce soil infiltration rate and may increase erosion by increasing runoff. We conducted rainfall simulation experiments on 30 cm×30 cm plots inclined at 9% slope in which we measured soil splash and wash erosion, runoff and splash volume for seventeen California soils. The soils ranged in clay content from 8 to 36%, ESP from