After five models of converting cropland to forest in low-mountain and high-mountain areas in Beichuanhe watershed of Datong county of Qinghai province were selected respectively

the hydrology effects were analyzed.The water-holding capacity of the canopy

litter layer and soil in different species arrangement models were increased along with biomass of the canopy and existent mass of litter layer.The water-holding capacity of soil was the biggest(>97%) in the total water-holding capacity of forest.The more the total pore space

the bigger the final infiltration rates.In the low-hill area

the total water-holding capacity of the canopy and litter layer of model D(Hippophae rhamnoides)was the biggest

that was 1.43 mm and 1.87 mm respectively;The total water-holding capacity of soil and forest of model C(Populus cathayana Lycium barbarum)

which was 327.88 mm and 329.07 mm respectively

ranks first place in different models of species distribution.The final infiltration rate of model A(Paeonia veitchii) is better than others

which is 4.8 mm/min.In the remote-hill area

the total water-holding capacity of canopy

litter layer

soil and forest of model F(Picea crassifolia) ranks first place in different models

which was 2.37 mm

6.24 mm

323.3 mm and 331.91 mm respectively

and the final infiltration rate of soil is 6.8 mm/min.