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Updated: Sep 29, 2025
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A Protocol for Conducting Rainfall Simulation to Study Soil Runoff
Published on: April 3, 2014
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Analysis of urea nitrogen leaching under high-intensity rainfall using HYDRUS-1D
Xiaoyu Mo1, Hui Peng2, Jia Xin2
1Key Laboratory of Marine Environment Science and Ecology, Ministry of Education and College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China.
Journal of Environmental Management
|March 21, 2022
Summary
Extreme rainfall significantly increases urea nitrogen leaching from farmland, polluting groundwater. Avoid fertilizer application before heavy rainstorms to minimize nitrogen loss and improve crop uptake.
Area of Science:
- Environmental Science
- Soil Science
- Agricultural Science
Background:
- Nitrogen leaching from farmland poses a risk of groundwater pollution.
- The impact of extreme precipitation events on urea nitrogen leaching remains unclear.
Purpose of the Study:
- To model and analyze urea nitrogen leaching under various extreme rainfall scenarios.
- To assess the influence of rainfall intensity and soil conditions on nitrogen loss.
Main Methods:
- Developed a nitrogen migration and transformation model using soil column experimental data.
- Simulated rainstorm, heavy rainstorm, and extreme rainstorm scenarios in the Dagu River Basin.
- Analyzed urea nitrogen leaching variations based on rainfall intensity and initial soil moisture.
Main Results:
- Urea nitrogen leaching increased from 0.04% to 18.09% with rising rainfall intensity.
- Cumulative urea nitrogen leaching flux was dependent on initial soil moisture content.
- Fertilizer application timing relative to rainfall significantly affected nitrogen loss and crop utilization.
Conclusions:
- Extreme rainstorms substantially increase urea nitrogen leaching into groundwater.
- Optimizing fertilizer application timing based on weather forecasts is crucial to mitigate nitrogen loss.
- Avoiding fertilization before high-intensity rainfall can reduce environmental pollution and enhance crop nitrogen use efficiency.
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