基于电容式湿度传感器的砂土水分含量测定  

Measurement of Soil Moisture Content of Sandy Soil Based on Capacitive Humidity Sensor

作　　者：田汇文 翟亚明[1,2] 唐瑞 褚浩洋 缪婧娴 TIAN Hui wen;ZHAI Ya ming;TANG Rui;CHU Hao yang;MIAO Jing xian(College of Agricultural Engineering,Hohai University,Nanjing 210098,China;The Experimental Teaching Center of Water Conservancy Projects,Hohai University,Nanjing 210098,China)

机构地区：[1]河海大学农业工程学院,南京210098 [2]河海大学水利工程实验教学中心,南京210098

出　　处：《节水灌溉》2019年第11期22-26,32,共6页Water Saving Irrigation

基　　金：国家级大学生创新创业训练计划项目(201810294118);“十三五”国家重点研发计划项目(2016YFC0400208);中央高校基本科研业务费专项资金项目(B19020180)

摘　　要：为了研究电容式土壤湿度传感器在砂性土壤蒸发不同阶段水分含量测定时存在测值偏差问题,采用直接称重求含水率法对比电容式土壤湿度传感器测量水分含量法,分析了初始饱和砂土柱蒸发条件下水分含量变化过程。结果表明;电容式湿度传感器量测法与电子秤量法在不同阶段含水率测值表现出差异性与相关性;传感器的插入影响试样蒸发过程:相较于原状土,前期扰动土蒸发速率偏高,中期偏低,后期基本一致。电容式湿度传感器测值偏差是由于插入电极薄片改变了原状土壤试样蒸发条件,其偏差程度与形成机理可从微观角度阐述,电容式土壤湿度传感器测量砂土蒸发过程中水分含量时具有分段式最佳表征形式。In order to study the problem of the measurement deviation of capacitive humidity sensor in the measurement of moisture content in different stages of sandy soil evaporation,the change process of water content of the initial saturated sandy soil column under evaporation condition was analyzed by direct weighing method compared with capacitive soil humidity sensor measurement method.The results show that the moisture content measured by electronic scale method and the capacitive humidity sensor method at different stages show difference and correlation;the insertion of electrode flake affects the evaporation process of the specimen;compared with the undisturbed soil,the evaporation rate of the disturbed soil is higher in the early stage,lower in the medium term and basically the same in the later stage.

关 键 词：砂土水分蒸发 电容式湿度传感器 含水率 测值偏差机理 分段式表征 

分 类 号：S152.7[农业科学—土壤学]