Assessing potential applications of multi-coil and multi-frequency electromagnetic induction sensors for agricultural soils in western Newfoundland

• Main Author: Sadatcharam, Kamaleswaran
• Format: Thesis
• Language: English
• Published: Memorial University of Newfoundland 2019
• Subjects: Newfoundland
• Online Access: https://research.library.mun.ca/13806/; https://research.library.mun.ca/13806/1/thesis.pdf

Ground-based electromagnetic induction (EMI) sensors play a significant role in shallow soil characterization in precision agriculture. Two different types of EMI sensors were used in this study: (i) a multi-coil and (ii) a multi-frequency. The potential applications of both EMI sensors have been assessed through two different studies at the Pynn’s Brook Research Station, Pasadena, western Newfoundland. One study was on the development of relationships between apparent electrical conductivity (ECₐ) and soil properties, using geostatistical and multivariate statistical approaches, and the second study investigated the depth sensitivity (DS) of multi-coil and multi-frequency EMI sensors using small buried targets of known properties in shallow soils. Soil properties, such as sand, silt, soil moisture content (SMC), cation exchange capacity (CEC), and pore water electrical conductivity (ECw), were identified as significantly influenced soil properties on ECₐ measurements. The multi-frequency EMI sensor is more reliable on ECₐ variability for wet soils than dry soils and it could explore deeper soil compared to the multi-coil sensor. The second study revealed that the multi-coil EMI sensor was a more accurate and suitable sensor to detect small metallic targets in the shallow soils than the multi-frequency EMI sensor. Finally, I concluded that the multi-coil EMI sensor is a more appropriate compared to the multi-frequency sensor, to investigate depth sensitivity (DS) analysis as well as the spatiotemporal variability of ECₐ as a proxy of soil properties in shallow (agricultural) soils in western Newfoundland.