Soybean Yield Simulation and Sustainability Assessment Based on the DSSAT-CROPGRO-Soybean Model.

Area of Science:

• Agricultural Science
• Agronomy
• Crop Physiology

Background:

• National grain and oil security necessitates expanding soybean cultivation in Xinjiang.
• Water scarcity and suboptimal planting technology in southern Xinjiang hinder soybean production.
• Lack of a supporting irrigation system limits soybean yield potential in the region.

Purpose of the Study:

• To determine the optimal irrigation amounts for maximizing soybean yield and water use efficiency in southern Xinjiang.
• To evaluate the accuracy of the DSSAT-CROPGRO-Soybean model for simulating soybean growth and yield under varying irrigation levels.
• To provide a theoretical basis for sustainable soybean cultivation in water-scarce regions.

Main Methods:

• Field experiments were conducted in 2022-2023 with three irrigation levels (27, 36, 45 mm) to measure dry mass and yield.
• The DSSAT-CROPGRO-Soybean model was calibrated and validated using meteorological data from 1994-2023.
• Model simulations assessed potential yield, biomass, and soil water storage under different irrigation scenarios.

Main Results:

• The DSSAT-CROPGRO-Soybean model accurately predicted soybean emergence, flowering, and maturity.
• Model predictions for biomass, soil water storage, and yield showed high accuracy (R² > 0.64).
• Soybean biomass increased with irrigation; optimal irrigation of 36-45 mm yielded up to 4984.73 kg·hm⁻², with maximum water use efficiency at 33-36 mm.

Conclusions:

• The optimal irrigation amount for soybean cultivation in southern Xinjiang is estimated to be between 36 and 42 mm.
• This irrigation range balances high soybean yield with efficient water resource utilization.
• The study provides critical data for developing effective irrigation strategies to enhance soybean production in arid and semi-arid regions.