便携式自动土壤观测仪校准测试方法

Calibration Test Method of Portable Automatic Soil Observation Instrument

针对自动土壤水分观测仪定期校准需要中断该设备正常连续观测时间以及设备送检的时间成本、运输成本和运输风险等问题,提出了一种自动土壤水分观测仪的现场校准方法。首先,分析了水分分布对铜环式自动土壤水分观测仪观测数据的影响;其次,设计了自动土壤水分观测仪在不同距离、同等水分条件下的电信号变化试验;最后,建立了自动土壤水分观测仪电场中水分分布对观测数据的影响模型,得到了水分分布与电场中心的距离和电信号变化之间的关系。结果表明,建立的模型在距离传感器外缘45 mm处,直径和高度均为10 mm的圆柱形水体的权重为0.015,能满足铜环式自动土壤水分观测仪分辨力0.02的要求,验证了便携式自动土壤水分观测仪检测方法的可行性。

In order to solve the problems such as interrupting the normal continuous observation time of the automatic soil moisture observation instrument during regular calibration,as well as the time cost,transportation cost and transportation risk of the equipment for inspection,a field calibration method of the automatic soil moisture observer was proposed.Firstly,the influences of water distribution on the observation data of copper ring automatic soil moisture meter were analyzed.Secondly,the electrical signal change experiment of the automatic soil moisture observation instrument under different distances and the same moisture conditions was designed.Finally,the influence model of water distribution on the observed data in the electric field of the automatic soil moisture observation instrument was established,and the relationship between the water distribution and the distance between the electric field center and the change of electric signal were obtained.The experimental results showed that the weight of the cylindrical water body with diameter and height of 10 mm was 0.015 at 45 mm from the outer edge of the sensor,which met the requirements of resolution 0.02 of copper ring automatic soil moisture meter.The feasibility of the method was verified.