Readiness of Vermicomposting Soil Conditioner Using Impulse Radar

Accurate assessment of vermicompost maturity is critical for optimizing soil management practices and ensuring high-quality soil conditioners. Traditional methods are subjective, labor-intensive, and lack precision, highlighting the need for advanced, non-invasive monitoring solutions. This study investigates impulse radar technology as an innovative tool for real-time evaluation of vermicompost readiness. An impulse radar system operating between <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$0.5-3.5 \text{GHz}$</tex> frequencies was assembled and tested across seven weeks of composting. Radargram grayscale images effectively differentiated maturity stages by capturing variations in moisture content and decomposition levels. Early-stage compost (week 1) exhibited low-intensity radar signals with scattered patterns due to high moisture content (<tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$35-40 \%$</tex>) and dielectric constants ranging from 10-18. By week 6, radargrams showed high-intensity, organized signals corresponding to reduced moisture (<tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{2 5}-\mathbf{3 0 \%}$</tex>) and dielectric constants of approximately 814, indicating near maturity. Fully mature compost at week 7 presented uniform radar signals with low dielectric constants (<tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$5-8$</tex>) and moisture content (<tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$20-25 \%$</tex>), confirming readiness for harvesting. A deep learning model was developed to classify compost maturity automatically from radargram images, achieving approximately 80 % accuracy in distinguishing early and mature stages. However, accuracy slightly declined when differentiating closely similar maturity levels (weeks 6 and 7). Impulse radar technology demonstrated significant potential as a rapid, efficient, and non-destructive method for monitoring vermicompost maturity. Integrating this technology into vermicomposting practices can enhance decision-making processes, improve compost quality control, and promote sustainable agricultural practices.