Study on Groundwater Evaporation with Lysimeters in Zhengzhou

Based on the lysimeter data from the experimental station on ground water balance in Zhengzhou, the relationship between phreatic water evaporation and weather,water table depth, soil and precipitation recharge is analyzed. It shows that phreatic water evaporation relates closely to surface evaporation on dynamic distributing when the depth is no more than 1 meter, that phreatic water evaporation will become weakened with the descend of the water table depth, that reasonable capillary height and permeability will result in a higher value of unconfined evaporation and that precipitation recharge has a great influence on the process of phreatic water evaporation when the depth is no more than 1 meter.