Research on the soil infiltration characteristics in the field

Based on the double-ring infiltration experiments carried out in the selected fields of the first terrace and the third terracewith sandy loamand clay loamrespectively inYanglingDistrict, Shaanxi Province, China, the soil infil- tration characteristics under different soil textures were studied. The results showed that the modified Kostiakov function was the optimal choice in describing the process of soil infiltration. The reasonable observing time of infiltration experi- ment was no less than 90 min in the first terracewith sandy loam and no less than 120 mins in the third terracewith clay loam. Based on the maximum correlation distance among the infiltration parameters, the reasonable sampling numberwas proved to be 42 for the selected fields in both the first terrace and the third terrace. The spatial variation characteristics of basic infiltration ratef0could be employed to describe the infiltration performance and to measure the infiltration ca- pacity of soil, and the spatial variation characteristics of the infiltration parameterkshould also be taken into considera- tion. The study results could set the scientific foundation for a further study of soil infiltration characteristics.