| By using an indoors incubation experiment plus a wild survey, three typical soils'water infiltration properties were studied in the Songnen meadow steppes. The field plots were located at the northern steppe of the NENU Songnen steppes Research Station in Yaojingzi, northwest of Changling County, Jilin Province. Selected soils are meadow soil, Black Calcium soil, and meadow alkali soil, respectively. The Black Calcium soil plots were conducted in farmland, the meadow soil in the Natural Reserves, and the meadow alkali soil in the degraded grassland with saline bowls. The indoors trials were placed at the Greenhouse of Faculty of Life Sciences, NENU. Finally, the results showed that:1. For the black calcium soil, meadow soil and meadow alkali soil from both indoors and field survey, the cumulative soil water infiltration amounts—I(t), increase by time for each, but the infiltration rates—i(t), decrease by time. The I(t) of the black calcium soil is the highest, whereas of meadow alkali soil is the lowest and medium for the meadow soil. The field tested cumulative I(t)s in 5 min, 10 min, and 30 min are all higher than that of indoors, while i(t)s in 0-5min, 5-10min, and 10-30min form field survey, are all higher than that of indoors.2. Regarding the impacts of gradient grazing pressures upon the meadow soil's water infiltration, both field survey and indoors experiments showed that, the cumulative infiltration amounts—I(t), increase by time under a same gazing pressure, while the infiltration rates—i(t), decrease by time. Between different grazing pressures, it showed no significance between no grazing and light grazing, no significance between medium grazing and heavy grazing, but significant between no- and light grazing and medium- and heavy grazing. The I(t)s from filed survey are higher than that from indoors experiments during 5min, 10min, and 30min, while i(t)s from field survey during 0-5min, 5-10min, and 10-30min, are higher than that from indoors trials.
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