摘要
给出了一种较简便、准确的时域反射仪(TDR)室内标定方法,该方法工作量小,克服了田间土壤水分空间变异的影响,更适用于粘壤土质的TDR标定。通过对昆山地区粘壤土质的实例标定发现,TDR测量值较烘干法明显偏低,绝对偏差范围0.02~0.09cm^3/cm^3,相对偏差随着土壤含水量的减小有增加趋势。但TDR的测量值与真实值之间有较高的相关性(R^2=0.9837,P〈0.001),可以用一个简单的线形函数进行校正,校正后的TDR测量值中将有98.4%的值接近土壤含水量真实值,说明该校正公式可以作为昆山地区进行TDR校正的参考。
A simple and exact method for laboratory calibration of TDR (Time domain reflectometry) is introduced. It has many advantages, such as less work intensity, hardly any spatial heterogeneity of soil moisture and more suitable for calibration on clay loam soil, compared with traditional calibration methods. Through the calibration for clay loam soil from Kunshan region, the results show that the measured values of TDR are obviously lower than that of the oven drying method(ODM), with a range of absolute deviation from 1.9 % --8.8 % (average 5.0 % ), and its relative deviation increases with the decrease of soil moisture. But, there is a high correlation between the measured value of soil moisture using TDR and ODM (R^2 = 0. 9837, P 〈 0. 001), which can be described by a simple linear function. The prediction equation can be used in Kunshan region as reference.
出处
《干旱地区农业研究》
CSCD
北大核心
2008年第1期249-252,共4页
Agricultural Research in the Arid Areas
基金
国家自然科学基金(50479022)
河海大学院士学科建设基金(2084/4021E7)
关键词
TDR
烘干法
土壤含水量
标定
TDR
oven drying method
soil moisture
laboratory calibration