Soil water availability is one of the key factors on the productivity of lithosols. The study results showed that the soil water availability has a closely relationship with the ratio of soil(fine earth <2 mm) and gravel (grain more than 2 mm). The abilities of soil vaporization

water retention

water conductivity and water supply are associated with the ratio of soil and gravel. Among the studied three types of soils with different ratio of soil and gravel

the soil with the lowest ratio of soil and gravel had highest water retention ability

while the soil with higher ratio of soil and gravel had lowest one. There was a positive relationship between soil water diffusivity and gravel capacity

but a negative relationship between soil vaporization and gravel capacity. A mezzo soil gravel ratio has a benefit on increasing water infiltration

soil water supply

and reducing soil water vaporization.