QQ客服 官方微博 反馈留言

	Development of Thermo-Time Domain Reflectometry for Vadose Zone Measurements
	Ren T. S. ; Ochsner T. E. ; Horton R.
	2003
英文摘要	Soil and environmental studies in the vadose zone are often restricted by the lack of equipment that can measure the variation of soil physical parameters in space and time. In this paper we demonstrate that thermo-time domain reflectometry (thermo-TDR) can be used for a wide range of soil physical measurements. The thermo-TDR probe combines TDR and heat-pulse technologies into a single probe. It allows measurements of volumetric soil water content (theta), temperature (T), electrical conductivity (EC), thermal conductivity (lambda), thermal diffusivity (alpha), and volumetric heat capacity (rho c) at the same sampling positions simultaneously. Furthermore, other soil physical parameters, such as bulk density (rho(b)), air-filled porosity (n(a)), and degree of saturation (S), can be determined from their relationships with rho c and theta. We examined the performance of the thermo-TDR using both published data and laboratory measurements on packed columns and intact cores from six soils of varying texture. The results show that the thermo-TDR provides reliable measurements of theta, EC, rho c, lambda, n(a), and S, but relatively large errors exist in rho(b). The average standard error between thermo-TDR measurements and gravimetric measurements is 0.026 m(3) m(-3) for theta, 0.050 m(3) m(-3) for n(a), 0.069 for S, and 0.134 Mg m(-3) for rho(b). The standard error between thermo-TDR measurements and theoretical predictions of rho c is 0.134 MJ m(-3) K(-1). These promising findings coupled with the characteristics of small probe size and easy automation make the thermo-TDR sensor an ideal tool for studying coupled flow processes in the vadose zone. Further improvements in probe design, waveform interpretation, and determination of effective probe length are also noted as steps toward improving accuracy and precision of future thermo-TDR measurements.
出处	Vadose Zone Journal
卷	2
期	4
页	544-551
收录类别	SCI
语种	英语
ISSN号	1539-1663
内容类型	SCI/SSCI论文
源URL	[http://ir.igsnrr.ac.cn/handle/311030/23144]
专题	地理科学与资源研究所_历年回溯文献
推荐引用方式 GB/T 7714	Ren T. S.,Ochsner T. E.,Horton R.. Development of Thermo-Time Domain Reflectometry for Vadose Zone Measurements. 2003.

个性服务

查看访问统计

相关权益政策

暂无数据

收藏/分享

除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。