ABSTRACT New calibration method of the capacitance and frequency domain reflectometry (ECH2O EC-5) for soil water monitoring was developed by introducing the slope-intercept relationship derived from the relationship between the RAW data recorded by the Em50 datalogger and the thermogravimetrically measured volumetric water content of soil. Numerous soil samples taken from paddy–upland rotational fields in western Japan were used for precise soil-specific calibration experiments to determine the variables of slope-intercept relationship. By using these identified variables and an easily available dataset of the measured volumetric water content and the RAW data, the developed linear function predicted volumetric water content of soils. The developed linear function was validated with the reported literature data, the agricultural fields experiment, and the laboratory experiment. From those three validations, the developed linear function was evaluated to be practically available for laboratory and field researches. Also, it is implied that the developed linear function is extendable to dataloggers except for the Em50 and monitoring devices excluding the EC-5.

中文翻译：

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通过引入斜截距关系校准电容和频域反射计 (EC-5) 用于土壤水分监测的线性函数

摘要 通过引入从 Em50 数据记录器记录的原始数据与热重测量的体积含水量之间的关系导出的斜率-截距关系，开发了用于土壤水分监测的电容和频域反射计 (ECH2O EC-5) 的新校准方法的土壤。取自日本西部稻田-旱地轮作田的大量土壤样品用于精确的土壤特定校准实验，以确定坡度-截距关系的变量。通过使用这些确定的变量和一个容易获得的测量体积含水量和原始数据的数据集，开发的线性函数预测了土壤的体积含水量。开发的线性函数通过报告的文献数据、农田试验、和实验室实验。从这三个验证中，开发的线性函数被评估为可实际用于实验室和现场研究。此外，这意味着开发的线性函数可扩展到除 Em50 之外的数据记录器和除 EC-5 之外的监控设备。