Abstract:In order to evaluate the effect of soil matrix improvement on soil erosion resistance during vegetation restoration of purple soil, relevant experiments were carried out in the purple soil area of Leiyang in south Hunan Province, China. Three soil matrix types were chosen in our study, including the untreated purple soil matrix (control land), the purple soil of interchanging topsoil with subsoil (soil replacement land), and the one added organic improver based on the soil replacement land (soil matrix improved land). Thirteen erosion resistance evaluation indexes were determined, the important indexes were screened out and an evaluation model was established to study the change of erosion resistance of purple soil substrate after soil matrix improvement, using the correlation analysis and the principal component analysis. The results showed that: (1) Compared with the control land, the organic carbon content, erosion resistant index, > 0.25 mm wet sieve aggregate content, > 0.5 mm wet sieve aggregate content, <0.002 mm clay percentage content, mean weight diameter of wet sieve aggregate, geometric mean diameter of wet sieve aggregate, structural granular index and aggregation condition in 0—10 and 10—20 cm soil layer increased by 69.19%~99.81%, 9.72%~46.86%, 41.69%~50.80%, 47.26%~58.98%, 73.82%~194.35%, 47.96%~57.01%, 49.06%~68.97%, 74.23%~183.25%, and 14.62%~20.16% in the soil matrix improved land, respectively. On the contrary, soil bulk density, fractal dimension of wet sieve aggregate and structural failure rate decreased by 10.53%~16.26%, 4.64%~7.58%, and 39.22%~54.64%, respectively. (2) Soil bulk density, organic carbon content and wet sieve aggregate content and stability were the main factors affecting the erosion resistance of purple soil. (3) Compared with the control land, the composite index of soil erosion resistance in 0—10 and 10—20 cm soil layer in the soil matrix improved land was significantly increased by 524.14% and 146.99%, respectively, and the one in the soil replacement land was increased by 93.10% and 42.17%, respectively. The results showed that the soil matrix improvement during vegetation restoration not only increased the organic carbon content of purple soil, but also significantly improved the soil erosion resistance, and this method can be used as an effective measure to control soil erosion in purple soil.