Soil Sensing Using EMI

Introduction

One of the fundamental deficiencies in many high value agriculture production systems is the lack of detailed, up-to-date and pertinent geo-referenced soil and water information. In almost all crops, detailed spatial soil and water data is essential to ensure the optimum long-term management (fertility, irrigation, drainage) of fields and sustainability of plants. Electromagnetic induction (EMI) methods are gaining popularity due to their non-destructive nature, rapid response and ease of integration into mobile platforms for characterization of variability in soil properties, water table depth, and salinity etc. EMI is a technique that measures the apparent soil electrical conductivity (ECa) by inducing an electrical current in the soil. It provides information about subsoil properties at a range of depths that are important to plant growth, which makes ECa unique for site-specific management because remote sensing and topographical information cannot directly assess subsoil properties. EMI data coupled with DGPS can be incorporated in geographical information system (GIS) to produce maps. Detailed georeferenced maps would be useful for site specific management and to assess the fertility status of the soil.

Objectives

Dual EM equipped with DGPS has been used to map variations in soil properties, water table depth and fruit yield in real-time. One of the objectives of the EMI instruments is to identify the relationships among the soil properties and ECa. Using the regression models soil properties, water table depth and fruit yield can be predicted from EMI survey data rapidly and reliably to develop site-specific technologies in wild blueberry fields. Recent work has produced interpolated GIS maps showing the relationships among the actual soil properties and ground conductivity. These maps can be used to delineate management zones based on variation in soil properties and fruit yield for site-specific fertilization.

Researchers

Dr. Qamar Zaman, Associate Professor, Engineering Department, NSAC

Kelsey Laking (Research Technician)

Aitazaz Farooque (Graduate Student)

Fahad Khan (Graduate Student)

Partners

This research was funded by Oxford Frozen Foods, Nova Scotia Department of Agriculture, Wild blueberry Producers Association of Nova Scotia, and Nova Scotia Water Expansion Program.