A study on water restoration of dry soil layers in the semi-arid area of Loess Plateau A study on the effect of soil moisture of different vegetations in Loess Hilly Region Alfalfa Growth Characteristics and Soil Water Dynamics of Grassland Converted from Cropland in Semi-arid Region Dry soil layer forming and soil moisture restoration of alfalfa grassland in the semi-humid region of the Loess Plateau THREE TEMPERATURE (3T) MODEL——A METHOD TO ESTIMATE EVAPOTRANSPIRATION AND EVALUATE