Modeling Study on Optimizing Water and Nitrogen Management for Barley in Marginal Soils

Area of Science:

• Agricultural Science
• Agronomy
• Soil Science

Background:

• Water and nitrogen are critical inputs limiting crop production, especially on marginal lands.
• Marginal soils present unique challenges for achieving optimal crop yields due to resource limitations.

Purpose of the Study:

• To evaluate the impact of water and nitrogen stress on spring barley yield in marginal soils.
• To utilize the AgroC model for simulating barley growth and identifying yield gaps.

Main Methods:

• Field trials were conducted from 2020-2022 in Lithuania with spring barley (cv. KWS Fantex).
• The AgroC model was parameterized using experimental data to simulate crop growth under varying water and nitrogen conditions.
• Yield potential and losses due to abiotic stresses were assessed through simulation.

Main Results:

• Potential yields ranged from 4.8 to 6.02 t DW ha⁻¹ under optimal conditions.
• Yield losses reached up to 54.4% from nitrogen stress and 59.2% from water stress, even with 100 kg N ha⁻¹ yr⁻¹.
• Optimal nitrogen fertilization rates (100-120 kg N ha⁻¹ yr⁻¹) varied with climatic conditions, introducing uncertainty.

Conclusions:

• Sustainable agricultural practices and advanced modeling are crucial for enhancing yield potential and resilience in marginal soils.
• Integrating remote sensing data can improve simulation accuracy and inform fertilization strategies.
• Optimizing water and nitrogen management is essential for improving barley production on marginal lands.