An improved approach to estimating the infiltration characteristics in surface irrigation systems
Mohamed Khaled Salahou1, Xiyun Jiao1, Haishen Lü1
1State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing, China.
Plos One
|June 17, 2020
Summary
This study introduces a new method to accurately estimate soil infiltration functions by combining double-ring infiltrometer (DRI) measurements with soil water content changes. The new approach improves reliability and reduces data scatter compared to traditional methods.
Area of Science:
- Agricultural Engineering
- Soil Science
- Hydrology
Background:
- Estimating soil infiltration functions is crucial for efficient irrigation management.
- Traditional methods like double-ring infiltrometers (DRI) and empirical models often suffer from data scatter and accuracy issues.
- Soil water content variability and measurement errors impact infiltration function reliability.
Purpose of the Study:
- To present a novel methodology for calibrating soil infiltration functions.
- To enhance the accuracy and reliability of infiltration function estimation.
- To investigate the effect of data scatter on infiltration function estimation.
Main Methods:
- Conducted furrow irrigation experiments to collect infiltration data.
- Combined double-ring infiltrometer (DRI) measurements with changes in soil water content.
- Utilized empirical models (Kostiakov model) for comparison.
- Observed furrow elevations, advance/recession times, and inflow rates.
Main Results:
- DRI-estimated infiltration depths were lower than observed depths.
- Empirical model (Kostiakov) estimated infiltration depths were higher than observed depths.
- The proposed combined method yielded more accurate and reasonable infiltration function estimates.
Conclusions:
- The new methodology offers a more accurate approach to estimating infiltration functions than DRI or empirical models alone.
- The proposed method effectively reduces data scatter caused by soil variability and measurement errors.
- This approach can potentially reduce the number of measurements needed during irrigation events.
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