Abstract: A method and system for generating a variable rate irrigation (VRI) prescription map for a large sprinkler irrigation system is provided. The method includes: determining a minimum length of a VRI management zone along a truss direction of the sprinkler irrigation system; determining a minimum angle of the VRI management zone along a travel direction of the sprinkler irrigation system; dividing the VRI management zone to generate a VRI management zoning map; determining, according to a basic irrigation amount of VRI management and a spatial distribution map of crop water deficit or a spatial distribution map of soil water holding capacity (SWHC), an irrigation quota of each management sub-zone; and generating, according to a distribution map of irrigation quotas of all management sub-zones in combination with a travel speed of the sprinkler irrigation system and a duty cycle of a solenoid valve, the VRI prescription map.

Abstract: A decision-making method for variable rate irrigation management includes the following steps: S1: sampling a soil from a root zone of a crop in an area controlled by an irrigation sprinkler, and measuring compositions of separates of the sampled soil; S2: managing and dividing the area controlled by the irrigation sprinkler according to an AWC of the soil in the root zone of the crop; S3: constructing an optimized soil moisture sensor network; S4: placing ground-fixed canopy temperature sensors; S5: constructing an optimized airborne canopy temperature sensor network centered on the center pivot; and S6: performing a variable rate irrigation by using the optimized soil moisture sensor network, the fixed canopy temperature sensors, the optimized airborne canopy temperature sensor network and an automatic weather station. The method optimizes the placement and quantity of the soil moisture sensor network and the canopy temperature sensor network to improve the measurement accuracy.

Abstract: A decision-making method for variable rate irrigation management includes the following steps: S1: sampling a soil from a root zone of a crop in an area controlled by an irrigation sprinkler, and measuring compositions of separates of the sampled soil; S2: managing and dividing the area controlled by the irrigation sprinkler according to an AWC of the soil in the root zone of the crop; S3: constructing an optimized soil moisture sensor network; S4: placing ground-fixed canopy temperature sensors; S5: constructing an optimized airborne canopy temperature sensor network centered on the center pivot; and S6: performing a variable rate irrigation by using the optimized soil moisture sensor network, the fixed canopy temperature sensors, the optimized airborne canopy temperature sensor network and an automatic weather station. The method optimizes the placement and quantity of the soil moisture sensor network and the canopy temperature sensor network to improve the measurement accuracy.