The invention discloses a method for monitoring and evaluating the
irrigation uniformity of underground
drip irrigation, and relates to the field of
irrigation and water conservancy. Comprising the following steps: selecting a
branch pipe unit in a
branch pipe rotation
irrigation group for field underground
drip irrigation, and selecting three
drip irrigation belts at the front, middle and rear parts of the
branch pipe unit at equal intervals; respectively arranging a pressure
observation point at the head end and the
tail end of each drip irrigation belt, and installing a pressure measuring device to measure the actually measured pressure value Pm; calculating the dripper flow qm at each pressure measuring device according to the actually measured pressure value Pm; the irrigation uniformity CU1 is calculated according to the dripper flow qm; a
soil moisture content observation point is arranged at the corresponding position where the pressure measuring device is installed, and a PR2 soil profile
moisture tacheometer is installed; after irrigation, adopting a PR2 soil profile
moisture tacheometer to observe the
soil moisture content of the soil layer in the preset range of each
moisture content
observation point within the preset time, and measuring once every preset depth interval; calculating the average value of the
soil moisture content of each different depth; calculating the average value of the soil moisture content of each observation point; calculating the soil
moisture distribution uniformity CU2 by utilizing a Criswensen formula by utilizing the average value of the soil moisture content of each observation point; calculating the irrigation uniformity CU of the underground drip irrigation according to the CU1 and the CU2; and evaluating the uniformity of the underground drip irrigation according to the uniformity CU of the underground drip irrigation, wherein the evaluation grades comprise excellent, good, general and poor. The method is easy and convenient to operate, economical and practical, the irrigation uniformity of subsurface drip irrigation can be accurately evaluated, more accurate
irrigation water effective utilization coefficient evaluation can be provided, actual production requirements can be better met, subsurface drip irrigation can be promoted to be applied to production practice, and the
water saving efficiency can be further improved.