Abstract
Abstract The West Liaohe Plain is a typical semi-arid area, where the process of rainfall infiltration to replenish groundwater is a key link in its vertical hydrological cycle. In this paper, we compare and analyze the impact upon soil moisture movement and water infiltration after the shift of irrigation method from flood irrigation to mulched drip irrigation under mulch through setting up in-field in-situ observation points and carrying out groundwater depth dynamic observation. The results show that compared with mulched drip irrigation under mulch, flood irrigation has a stronger response to rainfall infiltration and a quicker response time in the rise of underground depth. With the decrease of groundwater level, the effect of rainfall infiltration to replenish groundwater is significantly weakened. In the flood irrigation area, the groundwater depth at about 8 m already has no obvious response to a small amount of rainfall. However, the groundwater depth at 6 m in the area of mulched drip irrigation under mulch already has no response to rainfall. Therefore, when groundwater extraction is carried out in irrigation areas, reasonable groundwater extraction levels should be designated in light of different irrigation methods to maintain the sustainable utilization of groundwater.
Highlights
IntroductionAt the same time, when water-saving measures are contributing to the increase of crop yield, we should pay attention to the impact that these water-saving measures will exert on groundwater replenishment in related regions
Under the condition of a small rainfall, for instance a rainfall of 11.6 mm on July 7: for the flood irrigation area, the soil moisture content at the depth of 50 cm increased by 3.3% two hours after the rainfall, and the soil moisture content at the depth of 100 cm increased by 2% four hours after the rainfall; in the area of mulched drip irrigation under mulch, since the ground surface mulch has changed the condition of the underlying surface, rainwater falling on the mulch cannot directly infiltrate into the soil
Under the condition of a small rainfall, the rainfall infiltration depth in the flood irrigation area is less than 1.6 m, which is still within the phreatic limit evaporation depth
Summary
At the same time, when water-saving measures are contributing to the increase of crop yield, we should pay attention to the impact that these water-saving measures will exert on groundwater replenishment in related regions. The popularization of high-yield and high-quality crop varieties as well as the implementation of highefficiency fertilization technologies have led to a significant increase in the output of biomass per unit area, which has led to a substantial consumption of soil water. This means substantial decrease in the amount of underground water replenished from rainfall and irrigation water. In their researches on water quantitative transformation relationship between crop structure, crop yield, irrigation system, etc. and water quantity, Xuzhou Hanwang Hydrological Experiment Station and Baoding Ranzhuang Water Resources Experiment Station pointed out that highefficiency agricultural water utilization measures improve hydrological utilization efficiency along with their negative impact on groundwater replenishment (Wei & Ba )
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
