基于模拟降雨试验,从微结构、容重、抗剪强度角度分析了降雨过程中东北黑土结皮的发育过程特征,并探讨了黑土结皮的发育对土壤入渗的影响.结果表明:随着降雨的进行,东北黑土的表层结构逐渐致密,容重、抗剪强度不断增加,入渗能力下降;120min降雨历时内,黑土发育了厚约3-4min的稳定结皮层,结皮发生层孔隙度下降6.45%、容重增加14.13%;消除雨滴打击后(盖网处理),结皮发育强度减弱,120min降雨历时内,结皮发生层孔隙度下降3.27%、容重增加7.11%,均小于无盖网处理,但累积入渗量较后者高41.1%.东北黑土结构稳定,雨滴打击是其结皮发育的主导因子,降雨过程中未发现明显的颗粒淋移现象.
In a simulated rainfall experiment, the microstructure, bulk density, and shear strength of black soil were determined to study the development process of crust during rainfall, and the effects of the crust on soil infiltration. The results showed that with the process of rainfall, surface soil layer became compact, soil shear strength and bulk density increased, and infihration de- creased. In a period of 120 minutes rainfall, a stable crust layer in 3-4 mm thickness formed, whose bulk density increased by 14. 13% and porosity decreased by 6. 45%. The removal of raindrop beat weakened the development of crust, with soil porosity decreased by 3.27% , bulk density increased by 7.11% , and accumulated infiltration increased by 41.1%. The black soil in Northeast China had a stable soil structure, and raindrop beat was the dominant factor resulting in the development of crust. During the process of rainfall, no obvious eluviation was observed.