基于“电流-电压四端法”的温室栽培基质电导率测量  

Measurement of substrate electrical conductivity in greenhouse based on electrical current-voltage four-electrode method

作　　者：张俊宁[1] 李民赞[1] 孔德秀[1] 邹奇章[1] 王琦[1] 

机构地区：[1]中国农业大学现代精细农业系统集成研究教育部重点实验室,北京100083

出　　处：《吉林大学学报（工学版）》2007年第2期484-488,共5页Journal of Jilin University:Engineering and Technology Edition

基　　金：'863'国家基础研究计划项目(2003AA209040);国家自然科学基金资助项目(30370812)

摘　　要：研究了基于“电流-电压四端法”的温室栽培基质电导率测量方法和规律。试验结果表明:在保持基质盐分(离子总量)水平不变的条件下,若基质质量含水率低于50%,则电导率值受基质内离子含量和基质水分的双重影响。当基质质量含水率大于50%后,电导率主要受基质内离子总量的影响,可忽略水分的影响。控制基质质量含水率在65%左右时,仪器输出与基质溶液电导率呈幂函数关系,所建立的模型的决定系数达到0.970。控制基质质量含水率在45%左右的条件下,用幂函数和线性函数预测基质电导率都获得了较高的精度。The measurement of the electrical conductivity（EC） of the substrate in the greenhouse was performed by a portable real-time EC detector based on the electrical current-voltage foure-electrode method and its results were discussed. At the condition of constant salt content（total ion content）, if the water mass fraction in the substrate is lower than 50% ,its EC is determined by both the salinity and the moisture of the substrate. When the water mass fraction is higher than 50%, its EC is determined only by th fraction is set at 65 % and the substrate EC, e total ion content without connection with the moisture. When the water mass , the EC detector indicates a power function relation between the detector output and the correlation factor of the proposed model reaches 0. 970. When the water mass fraction of the substrate is about 45%,its EG can be predicted accurately by both the power function as well as the linear function models.

关 键 词：农业工程 温室基质 电导率 电流-电压四端法 精细农业 

分 类 号：S24[农业科学—农业电气化与自动化] TH7[农业科学—农业工程]