Soil physical properties and water conservation of Natural Quercus mongolicaforest were studied atdifferent slope positions in the mountainous area of Northern Hebei Province.The results showed that soilbulk density

soil non-capillary porosity

and effective water storage at the upper 40cm soil layer varied atdifferent slope positions

in a descending order as middle slope>lower slope>upslope.Soil bulk density varied between 1.0g/cm3 and 1.1g/cm3.The means of soil non-capillary porosity and effective water storageamount were 8.9%and 347.6t/hm2

respectively.Soil capillary porosity

total porosity

soil capillary waterstorage and maximum water storage at different slopes had average values of 38.5%

47.5 %

1 521.5t/hm2

and 1 869.1t/hm2

respectively

with the highest values at lower slope and the lowest at upslope.The litter thickness

total litter and maximum water storage had averages of 48.7cm

23.6t/hm2

and 49.3t/hm2

respectively

and can be ranked in terms of slope positions as:lower slope>upslope>middle slope.Maximum water holding capacity varied from 219.34%to 231.8%

exhibited highest values at upslope

followed by middle slope

and then lower slope.Water storage of the forest at different positions can be arranged in a descending order as:lower slope(1 996.0t/hm2)>middle slope(1 930.0t/hm2)>upslope(1 829.3t/hm2).The average value of water storage was 1 918.4t/hm2.The results indicated that waterstorage capacity of natural Quercus mongolicaforest was significantly affected by slope position.