ARS | Publication request: SOIL ELECTRICAL CONDUCTIVITY MAPPING

Submitted to: Potash and Phosphate Institute Guides
Publication Type: Other
Publication Acceptance Date: November 1, 2000
Publication Date: N/A

Technical Abstract: Precision farmers can now collect more detailed information about the spatial characteristics of their farming operations than ever before. In addition to yield, boundary, and field attribute maps, a wide array of new electronic, mechanical, and chemical sensors are being developed to measure and map many soil and plant properties. Soil electrical conductivity (EC) is one of the simplest, least expensive soil measurements available to precision farmers today. Soil EC is a measurement that correlates to soil properties affecting crop productivity including soil texture, cation exchange capacity, drainage conditions, organic matter level, salinity, and subsoil characteristics. With field verification, soil EC can be related to specific soil properties that affect crop yield, such as topsoil depth, pH, salt concentrations, and water-holding capacity. Soil EC maps often visually correspond to patterns on yield maps and can help explain yield variation. The EC data can also be correlated with yield, elevation, plant population, surface hydrology or remotely sensed data with a suitable Geographical Information System (GIS). Other uses of soil EC maps include guiding directed soil sampling, assigning variable rates of crop inputs, fine-tuning USDA-NRCS soil maps, improving the placement and interpretation of on-farm tests, salinity diagnosis, and planning drainage remediation. Interest will continue to grow in soil EC mapping as a valuable tool for crop producers developing precision agricultural plans.