Multisensor Capacitance Probes for Simultaneously Monitoring Rice Field Soil-Water- Crop-Ambient Conditions

Area of Science:

• Agricultural Engineering
• Environmental Science
• Soil Science

Background:

• Multisensor capacitance probes (MCPs) are established tools for soil moisture monitoring and irrigation.
• Traditional MCP applications do not encompass simultaneous water level and temperature profiling.

Purpose of the Study:

• To introduce and validate a novel application of MCPs for simultaneous monitoring of ponded water level, soil moisture, and temperature profiles in rice cultivation.
• To assess the performance and accuracy of MCPs in a real-world rice field setting.

Main Methods:

• MCPs integrated with WiFi-based loggers and ultrasonic distance sensors collected concurrent data.
• Laboratory calibration of MCPs for water depth versus volumetric water content (VWC) was performed.
• Field measurements were conducted throughout a rice growing season to verify the methodology.

Main Results:

• The developed MCP system accurately monitored ponded water depth, soil moisture, and temperature profiles.
• The root-mean-squared error for water depth calculation using MCP VWC was 6.6 mm.
• The insulating effect of ponded water on temperature was quantified at different water levels.

Conclusions:

• MCPs offer a versatile and accurate method for simultaneous monitoring of key environmental parameters in rice fields.
• This integrated approach provides a holistic understanding of the soil-plant-atmosphere continuum.
• The technology enhances precision agriculture for rice cultivation, particularly in regions with variable water and temperature conditions.