土壤水分剖面测量系统设计与应用性能检验

针对农田环境下观测不同作物根区土壤水分变化的实际需要，研制了一种可快速获取0～200 cm深度范围内土壤剖面含水率的传感器及其测量系统。其中水分传感器工作原理为基于电容边缘场效应测量电极周围介质的介电常数，与土壤接触采用PVC套筒式结构，深度测量为霍尔磁敏传感器阵列，测量系统数据处理平台为PDA。对于测量方法的理论研究，该文给出了传感器工作原理的解析分析，进一步提出了传感器应用性能检验的试验方法。结果表明，该传感器性能指标达到实际应用需求，具备应用推广价值。

Design and applicable evaluation of instrument for determining soil moisture profile

For monitoring soil moisture profile in relation to the root-zones of various crops, an instrument, which could measure soil moisture over a range depth of 0-200 cm, was developed. The principle of soil moisture sensor was based on the fringe-effect of capacitor and the dielectric prosperity of medium surrounding electrodes. When moved up or down in an access tube embedded into soil, the designed probe could sense the moisture profile real-time. The depth transducer consisted of a sensor array of Hall-magnetism components, and a PDA was employed as data-logger. Furthermore, this paper presented the analytical approach on the measurement method, and proposed the experimental method for evaluating the feasibility in the field. Results showed that the system performance index agreed reasonably well with the practical application and it was worthy for recommendation.