Investigating runoff formation dynamics: field observations at Cape Fear experimental plot.

Area of Science:

• Hydrology
• Environmental Science
• Soil Science

Background:

• Understanding surface runoff formation is crucial for water resource management and flood prediction.
• Experimental plots provide high-resolution data for hydrological process studies.
• The Cape Fear plot offers a unique combination of small-scale and catchment-scale features.

Purpose of the Study:

• To investigate the relationships among rainfall, soil moisture, and surface runoff dynamics.
• To analyze the hydrological response of the Cape Fear experimental plot over five years.
• To identify factors influencing surface runoff formation in a controlled experimental setting.

Main Methods:

• Monitoring 101 rainfall-runoff events over more than five years (January 2014-March 2019).
• Utilizing the 7x7 m² Cape Fear experimental plot for high temporal and spatial resolution data collection.
• Analyzing the interrelations between rainfall intensity, soil moisture content, and direct runoff volume.

Main Results:

• A non-linear, increasing relationship was observed between rainfall and runoff response.
• The surface runoff coefficient increases with higher rainfall amounts.
• Direct runoff positively correlates with soil moisture, while initial abstraction decreases with increasing soil moisture.

Conclusions:

• Hydrological variable relationships in the Cape Fear plot are complex and spread.
• Soil moisture conditions and rainfall patterns significantly modulate plot runoff response.
• Findings highlight the importance of considering antecedent soil moisture in runoff prediction models.