Assessing Subsoil Conditions with an ASABE Conform Vertical Penetrometer-Development and Evaluation

Area of Science:

• Soil Science
• Agricultural Engineering
• Environmental Monitoring

Background:

• Subsoil is vital for water, nutrient, and carbon storage, impacting crop yield and resilience.
• Climate change and resource scarcity necessitate better subsoil assessment tools.
• Existing penetrometers lack the ability to measure subsoil properties accurately due to high forces and friction.

Purpose of the Study:

• To develop a novel tractor-mounted subsoil penetrometer for measuring conditions up to 2m depth.
• To integrate a soil water content sensor for comprehensive subsoil analysis.
• To overcome challenges of high penetration forces and shaft friction in compacted subsoils.

Main Methods:

• Designed a tractor-mounted penetrometer with an ASABE standard cone and a protected rod housing an FDI moisture sensor.
• Implemented a lateral shifting tower for single-line probing without tractor movement.
• Evaluated performance in compacted loamy silt soil boxes and field trials against a standard penetrometer.

Main Results:

• The developed penetrometer effectively measures penetration resistance without influence from shaft friction.
• An optimal distance of at least 10 cm between the cone tip and protection shaft is required for accurate readings.
• Field trials confirmed the penetrometer's stability, precision, and suitability for subsoil access.

Conclusions:

• The developed subsoil penetrometer is a stable and precise tool for assessing subsoil properties.
• It provides crucial data for understanding soil health, water management, and site resilience.
• This innovation addresses a critical need for advanced subsoil monitoring in agriculture and environmental science.