Comparative Study on Different Determination Methods of Soil Moisture
LI Yan et al(Department of Hydraulic Engineering,Tianjin Agricultural University,Tianjin 300384)
[Objective] The purpose of the study was to provide theoretical foundation for determining soil moisture content by using TDR and FDR methods correctly.[Method] With oven drying in aluminum-box as standard,through checking TDR and FDR methods,their advantages and disadvantages and the influence of soil temperature on determination results were confirmed.[Result] The results from indoor simulated test showed that the 3 curves had same change trends;when the abscissa value was in 3.0-23.0,θT was closer to true value(θv) than θF;when the abscissa value was in 18.0-23.0,θT was basically consistent with θv;when the abscissa value was bigger than 23.0,θv,θT and θF had tiny difference.The results from field experiment indicated that except for the points 2,3,4 and 8,the determination results of FDR had quite much difference from θv and that of TDR had quite little difference from θv.The results from integrated analysis showed that the curve of FDR was lowest and always kept some distance from the curve of θv,they only had 2 juncts;both the curves of TDR and θv were above,they had very little distance and possessed 7 juncts,indicating that the determination accuracy of TDR was higher than that of FDR.[Conclusion] The determination of soil moisture content by using TDR method was accurate,convenient and fast.
【CateGory Index】： S152.7