LAUSR

Abstract Natural restoration age of abandoned farmlands has significant effects on near soil surface characteristics and thus affects soil erodibility. However, few studies have been conducted to investigate the potential effects of natural restoration age on soil erodibility on the Loess Plateau where many slope farmlands have been abandoned for soil erosion control in the past decades. This study was performed to quantify the effects of natural restoration age on soil erodibility reflected by soil cohesion (Coh), saturated conductivity (Ks), the number of drop impact (NDI), the mean weight diameter of soil aggregates (MWD), soil penetration resistance (PR), and soil erodibility K factor. One slope farmland (as the control) and six abandoned farmlands restored for 3 to 33 years were selected for soil indicators measurements. A weighted summation method was used to produce one comprehensive soil erodibility index (CSEI) to demonstrate comprehensively the temporal variation in soil erodibility with natural restoration age. The results showed that Coh, Ks, NDI, and MWD increased generally when the restoration age