中文摘要：

采用我国不同土壤类型地区的5种土壤样品，利用自行设计的近红外传感器测量不同土壤含水率对应的反射光强。选取中心波长1940nm的近红外光为测量光，1800nm为参考光，将两波长的反射光强值换算为相对吸收深度。实测结果表明，随着土壤含水率的增加，相对吸收深度增加，两者间呈线性相关关系。选取独立样品对线性标定模型进行验证，除红土外，其他4种样品的均方根误差均小于6％。通过标定，所设计的传感器能够较好地测定不同土壤的含水率。

英文摘要：

The sensor for soil moisture measurement should have broad adaptability, and the soil moisture can be measured by the sensor upon the determination of the relationship between soil moisture and relevant variable. Five typical soils from different geographic locations of China were sampled for soil moisture measurement test with the near infrared sensor designed with 1 940 nm as measuring wavelength and 1 800 nm as reference wavelength. The reflectance of those two wavelengths was transformed to relative absorbance depth to minimize the influencing factors. The results indicate there existing strong linear correlation between soil moisture and relative absorption depth for different soils. Independent data sets were used to validate the calibration model, and the root mean square error is less than 6% except for the red soil from southern China. The research shows the adaptability of the sensor for different soils and the calibration steps.