An IoT based Portable Sensory System for the Accurate Analysis of Soil Macronutrients using Photometry

Nitrogen, Phosphorus, and Potassium (NPK) as elemental macro nutrients are highly indispensable for augmenting agricultural productivity. The amalgamation of NPK sensors with Internet of Things (IoT) technology within the domain of precision agriculture has garnered substantial scholarly interest. This integration facilitates the contemporaneous and meticulous monitoring of soil nutrient levels, thereby allowing farmers to discerningly optimize Fertilizer Use Efficiency (FUE). Such precision not only engenders heightened crop yields but also serves as a bastion against soil pollution, thereby reinforcing environmental stewardship to bolster the economic sustainability of farmers. In the multifaceted context of varying nutrient exigencies across diverse crop species at different testing intervals within agro-ecosystems, rapid development is highly necessitated. In response to this constraint, the current scholarly discourse expounds upon the pioneering development of an innovative NPK sensor, rooted in the venerable photometric principle. The crux of this method lies in the detection and quantification of light refraction in the resultant solution, meticulously orchestrated through the perceptive deployment of a Light Dependent Resistor (LDR) and a sophisticated ARM microcontroller. The efficacy and precision of this system are corroborated through the rigorous application of statistical models, thereby substantiating its operational linearity to mark a significant step toward sustainable and efficient agricultural practices.