Knowledge of mechanical dispersion and accurately determination of soil water fluxes in porous media are of prime importance for simulating soil and groundwater contamination, transport of agricultural chemicals, waste water renovation and plant nutrient uptake. However, solute dispersion and soil water flux are difficult to determine in situ because of its considerable variation both spatially and temporally and the unknown history of the solute source. Recently, Dr. Lu Xinrui and Prof. Li Xiujun et al from the Chinese Academy of Sciences' Northeast Institute of Geography and Agroecology (IGA) performed a systematic and quantitative comparison of the characteristics of coupled heat and solute dispersion using heat and Cl? as tracers on three types of saturated packed media (a sand, silt loam and sandy clay loam soil) using the thermo–time domain reflectometry by an inverse model. Moreover, they explored experimentally how thermal dispersion influenced the estimates of soil water flux density. These findings demonstrated that heat dispersion could be compared to solute dispersion, and quantify the magnitude of solute dispersion using and vice versa. Furthermore, soil water flux in situ were in better accurate determination if considering heat dispersion. "This is a very good paper, said one of the reviewers, "it is an important new discovery in the measurement of water flux by heat pulse technology considering heat dispersion, which will open the door to wider use of the method."
Relevant research results were published in the Journal of European journal of soil science, Catena, and Archives of Agronomy and Soil Science. 
Figure.1. Soil water fluxes (J) estimated using the ration method including heat dispersion with that ignoring heat dispersion in sand, silt loam and sandy clay loam. 
Figure.2. Comparison of heat and solute dispersivities plotted against water fluxes (Jw) on the (a) sand, (b) silt loam and (c)sandy clay loam soils Download the attachment：
https://DOI: 10.1111/ejss.12789
https:/DOI: 10.1016/j.catena.2018.04.041
https://DOI: 10.1080/03650340.2016.1218478
Email: luxinrui@iga.ac.cn |
