Two-dimensional finite elements model for boron management in agroforestry sites.

Area of Science:

• Environmental Science
• Soil Science
• Agricultural Engineering

Background:

• Agroforestry is recommended for managing drainage-impacted areas in California's San Joaquin Valley.
• However, these systems can cause excessive boron accumulation in the soil root zone.

Purpose of the Study:

• To develop and validate a mathematical model for simulating long-term boron buildup in agroforestry systems.
• To assess the impact of soil properties and root uptake on boron transport.

Main Methods:

• A dynamic two-dimensional finite element model was developed to simulate water flow and non-conservative boron transport.
• The model incorporates boron sorption and root-water extraction processes.
• Model simulations were validated against two field data sets.

Main Results:

• The model accurately simulated field data with low errors (MAE 1.5 mg/L, RE 6.5%).
• Boron adsorption was highest in silt loam soils compared to sandy loam and clay loam soils.
• Boron uptake by roots and soil's adsorptive capacity were identified as sensitive parameters influencing boron distribution.

Conclusions:

• The developed model is effective for simulating boron transport and buildup in agroforestry systems.
• Soil type significantly affects boron adsorption, with silt loam soils showing higher capacity.
• Understanding root uptake dynamics is crucial for managing boron levels in agricultural soils.