ABSTRACT
ABSTRACT: Soil infiltration is a key factor in the process from rainfall to runoff, and the vegetation plays an important role in the process of soil infiltration. Many observation experiments and simulation experiments have been carried out in Inner Mongolian in order to study the affection of vegetation on soil infiltration. The soil water content was measured by Time Domain Reflectomtry with Intelligent Microelements pre-rainfall and post-rainfall in difference fields, in which vegetation coverage was 18%, 30%, 33% respectively. All the results, according to the observation data, can be concluded as follows: (1) it is more conducive to soil infiltration with the higher vegetation coverage. The natural rainfall only increase the soil moisture of surface layer in the area with 18% vegetation coverage, and the same rainfall can increase soil moisture in 30 cm significantly. (2) The continuous rainfall can increase the depth of influence, the observed data show that the soil moisture increased in 30 cm in the area with 18% vegetation coverage, while the influence depth was deeper in the higher coverage plots, the changes in 40 cm have been observed in the area with over 30% vegetation coverage. (3) Compared with the uphill, soil infiltration in downhill is more evidence under the same rainfall and vegetation coverage conditions. (4) Soil air, imprisoned in the soil by rainfall, can not only hobble the infiltration water movement, but also occupation the liquid phase space under wetting front due to the pressure.
