Simulation of Mulch and No-Mulch Conditions for Various Soil Matric Potential Thresholds for Drip-Fertigated Guava (Psidium guajava L.) in the Semiarid Region of Northwest India

AbstractField experiments were conducted in a semiarid region of Punjab state, northwest India, for 2 years to evaluate an efficient irrigation schedule for guava under mulch and no-mulch conditions. The experiment involved the effect of mulching and three irrigation threshold values [I1 (−20  kPa); I2 (−40  kPa); and I3 (−60  kPa)] on guava plants under drip irrigation and fertigation. Soil matric potential, irrigation amount, soil water content, and fertilizer (N, P, and K) content were measured, and seasonal crop evapotranspiration as well as water and fertilizer use efficiency were computed regularly during the growing period of the crop. The calibrated two dimensional (2D)/three-dimensional (3D) model was used to simulate soil matric potential, and water and fertilizer movement in the soil under guava trees for mulch and no-mulch conditions. Simulated water movement, soil matric potential, and N, P, and K movement statistically matched those measured using the tensiometers, soil water probes, and soi...