Mid-infrared spectroscopy: An effective tool to enhance the Soil Health Card scheme in India

Periodically assessing the soil’s health is very important to show the effect of current agricultural practices on the soil and maintain soil nutrients at optimum levels using new management practices.  Mid-infrared (MIR) spectroscopy provides an alternative highly effective method for rapidly and cost-effectively estimating soil properties.

Precision fertilizer management at scale requires a thorough understanding of the spatial variability of soil characteristics. The rapid analysis of large numbers of soil samples within a short span of time is necessary for fertilizer recommendation. However, conventional methods of soil analysis (wet chemistry) are expensive, laborious, time-consuming, and rely on hazardous chemicals.

Mid-infrared (MIR) spectroscopy provides an alternative highly effective method for rapidly and cost-effectively estimating soil properties. MIR spectroscopy is a dry-chemistry-based soil analysis that does not use chemical reagents. Instead, it measures the amount of light reflected by a soil sample in the mid-infrared spectral regions as it reacts to its organic and inorganic composition.

Soil moisture, organic matter, carbonates, minerals, and texture are the main constituents influencing the shape of soil reflectance in the MIR region. Additionally, a single spectrum is sufficient for determining the properties of various soils.