Evaluation of infiltration models in contaminated landscape

Area of Science:

• Soil Science
• Hydrology
• Water Resource Management

Background:

• Infiltration modeling is crucial for understanding water movement in soils.
• Common models include Kostiakov, Green-Ampt, and Philip equations.
• Accurate parameter estimation is vital for reliable simulation.

Purpose of the Study:

• To calibrate and evaluate Kostiakov, Green-Ampt, and Philip infiltration models.
• To compare model performance across nine diverse soil types.
• To identify the most suitable model for simulating in-situ infiltration and estimating soil hydraulic conductivity.

Main Methods:

• Utilized Kostiakov, Green-Ampt, and Philip (two- and three-term) infiltration equations.
• Employed the Osborne-Moré modified Levenberg-Marquardt algorithm for parameter optimization.
• Calibrated and validated models using experimental data from double-ring infiltrometers.

Main Results:

• All tested models demonstrated capability in simulating cumulative infiltration across different soil types.
• Kostiakov's equation showed limitations in simulating long-term infiltration rates.
• Philip's two-term equation occasionally yielded unrealistic negative saturated hydraulic conductivity values.

Conclusions:

• Philip's three-term equation is recommended for accurate infiltration simulation and saturated hydraulic conductivity estimation.
• The chosen optimization algorithm effectively estimated model parameters.
• Model selection is critical for reliable hydrological assessments in varied soil conditions.