Development of On-the-Go Proximal Soil Sensor Systems

To implement sustainable agricultural and environmental management, a better understanding of the soil at increasingly finer scales is needed. Conventional soil sampling and laboratory analyses cannot provide this information because they are slow and expensive. Proximal soil sensing (PSS) can overcome these shortcomings. PSS refers to field-based techniques that can measure soil properties from 2 m or less above the soil surface. The sensors may be invasive, or not, and may or may not be mounted on vehicles for on-the-go operation. Much research is being conducted worldwide to develop sensors and techniques that may be used for proximal soil sensing. These are based on electrical and electromagnetic, optical and radiometric, mechanical, acoustic, pneumatic, and electrochemical measurement concepts. This chapter reviews the latest of these technologies and discuss their applications.