Response of soil multifractal characteristics and erodibility to 15-year fertilization on cropland in the Loess Plateau,China

Understanding the influence of long-term fertilization on the multifractal characteristics and erodibility of soil of cultivated land on the Loess Plateau of China could help prevent soil erosion and promote the sustainable development of agriculture. We collected 27 soil samples from 0 to20 cm layers of nine fertilizer treatments. Rényi spectrum (D_q) and singularity spectrum (?(α)) were applied to characterize soil particle-size distribution (PSD). The multifractal parameters of capacity dimension (D₀), entropy dimension (D₁), Hölder exponent of order zero (α₀), and erodibility K and anti-erodibility indices (aggregate state and degree) were used to determine the effect of fertilization on soil properties and erodibility. The multifractal models could characterize the PSDs in the various fertilizer treatments well. Treatments receiving manure had higher D₀, D₁, α₀, soil organic carbon (SOC) content, aggregate state and degree and lower erodibility. It was concluded that D₀, D₁, and α₀ could clearly discriminate among the various treatments, and the combined application of mineral fertilizers and organic manure greatly improved soil quality and structure of the cultivated land in the Loess Plateau. Furthermore, changes of multifractal parameters D₀, D₁, and α₀, especially D₁, was mainly due to the reduced soil erosion and the increase of SOC.