Study on the Particle Size Composition and Erodibility of Different Salinized Soils in Delingha City

In order to reveal the particle composition of different salinized soils and its relationship with soil erodibility K value in Delingha City of Qinghai Province, the EPIC model based on the mechanical composition and organic carbon volume content was used to estimate the soil erodibility K value, the soil particle size distribution, erodibility K value and their relationship of five kinds of salinized soils in this area were analyzed. The results showed that: on the whole, the soil particles in Delingha City were mainly composed of powder particle (55 % -84 %) and sand grain (15 % -44 %). With the increase of salinization degree, the soil texture gradually became finer. The K value of erodibility factor was ranged from 0.048 to 0.061, with an average value of 0.054. According to the classification standard of soil erodibility K value, the soil in the study area belonged to the soil with high erodibility (K＞0.048), and there was a high risk of erosion. By analyzing the correlation between the K value of soil surface erodibility and the composition of 8 soil particle sizes, it was found that the K value of erodibility factor was significantly positively correlated with clay particle and powder particle (P＜0.01). It showed that the salinization of surface soil in Delingha City was serious, and the increase of fine particles made the erodibility factor K value increase, and the soil was more susceptible to erosion