Multi-scale resistivity imaging for soil moisture and structure characterization in precision agriculture

Area of Science:

• Geophysics
• Soil Science
• Agronomy

Background:

• Sustainable tropical agriculture requires detailed soil water dynamics knowledge.
• Topography, soil texture, and climate significantly influence water availability.

Purpose of the Study:

• To integrate Electrical Resistivity Tomography (ERT) and Electromagnetic Induction (EMI) for characterizing soil moisture and subsurface texture.
• To assess water retention and availability in contrasting Indonesian agricultural landscapes.

Main Methods:

• Employed ERT for high-resolution vertical soil profiles up to 5m depth.
• Utilized EMI for lateral resistivity mapping at fixed depths.
• Combined geophysical data with field observations and soil profile analysis.

Main Results:

• ERT and EMI successfully delineated soil moisture variations and textural heterogeneity across diverse landscapes (Subang, Bandung, Sumedang).
• Low resistivity in Subang indicated saline clay loam with a shallow water table; high resistivity in Bandung suggested well-drained sandy soils.
• Intermediate resistivity in Sumedang revealed deep moisture storage in clay layers beneath drier topsoil, influenced by terracing.

Conclusions:

• Integrated geophysical imaging effectively maps soil moisture variability and subsurface heterogeneity.
• Slope, soil texture, and drainage are critical factors governing water retention.
• This non-invasive approach supports precision agriculture strategies in tropical environments.