Application Characteristics and Trend of Soil Moisture Potential Method

In 1980s,the Zero Flux Plane method is applied to solve the problems from the uncertainty parameters in the transformation of the precipitation,surface water,soil moisture and groundwater in our country,which shows that the total soil moisture potential gradient is greater than 1.0 cm H2O/cm in the process of the precipitation infiltration of groundwater supply and gradual reduction,and indicates that the total soil moisture potential gradient is approaching to 1.0 cm H2O/cm flowing in and out of the water by monitoring soil layers.In the 1990s,the relationship between the soil water potential and the soil water content to guide the agricultural water saving irrigation demonstrates that the excess irrigation and more water waste can be realized when the soil moisture potential gradient is approaching to 1.0 cm H2O/cm and soil is longer in the process of irrigation.In the 21 century,the groundwater numerical simulation rise again.The soil moisture potential theory is used to solve the soil water salt migration.Numerical modeling and the hydrogeologic parameters in the infiltration model is introduced to water gas migration change mechanism.The different characteristics of these polymer profiles are in different hydrodynamic condition.The soil moisture potential-gradient profiles point to the surface.Its absolute value is much larger than 1.0 cm H2O/cm with the formation of salt accumulation to the upper of the soil profile.The soil moisture potential gradient point to groundwater table in the upper of the profile and point to the surface in bottom of the profile with the formation of salt accumulation to the middle of the soil profile.The soil moisture potential gradient profiles point to groundwater table.Its value is much larger than 1.0 cm H2O/cm with the formation of salt accumulation to the bottom of the soil profile.