ABSTRACT

    Soil temperature and pH strongly influences nutrient dynamics, microbial activity, and crop productivity, making accurate monitoring essential for precision agriculture. This study evaluated the accuracy, repeatability, and precision of multiparameter soil sensors in loam, sandy, and clay soils, using a digital meter as reference. Temperature accuracy was assessed through Mean Absolute Error (MAE) and Bland–Altman plots, while pH accuracy was analyzed using the same tools. Repeatability and precision were measured with Coefficient of Variation (CV) and Intraclass Correlation Coefficient (ICC). Results showed strong temperature accuracy, with MAE values of 0.87 °C (loam), 0.93 °C (sandy), and 0.90 °C (clay), all within the ±1 °C threshold. pH accuracy was moderate, with MAE values of 0.62, 0.98, and 1.04, reflecting overestimation in sandy and clay soils. Precision was acceptable (CV < 2.5% for temperature; 3–4% for pH), though ICC values (0.34–0.47) indicated moderate agreement. Multiparameter sensors are reliable for temperature but require calibration for pH.

KEYWORDS

Multiparameter soil sensor; Temperature monitoring; pH measurement; Precision agriculture; Accuracy and reliability 

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