水土保持学报2017，Vol.31Issue(2)：111-116,6.DOI:10.13870/j.cnki.stbcxb.2017.02.020
基于NMR技术的盐渍化冻融土壤未冻水及孔隙水含量试验研究
NMR-based Research on Unfrozen Water and Pore Water Content in Saline Freezing-Thawing Soils
摘要
Abstract
To explore the changes of pore and unfrozen water contents in saline soils during the freezingthawing process,the pore and unfrozen water contents in different saline soils and NaCl saturated soil samples were determined using nuclear magnetic resonance spectrometer (NMR) to detect,the effects of soil texture on unfrozen water content in the freezing process were studied,and the hysteresis during the freezing-thawing process was analyzed.Eight treatments were designed,i.e.two types of soil (mild saline silt loam and moderate saline loam) and four types of solution (distilled water,0.2％ NaCl,0.6％ NaCl and 1.0％0 NaCl solutions).The findings were as follows:(1) macropores showed a faster decrease in unfrozen water content than micropores during the process of salinized soil freezing,with the thawing dissolved first in micropores in salinized soil.(2) For both the slight and moderate salinized soils,unfrozen water content was the maximum when the soils were treated with 1.0％ NaCl solution.(3) As could be seen from the comparison of unfrozen water content between different soils during the freezing-thawing process,the loam had higher unfrozen water content than the silt loam.According to the experimental results,water content reduction started in macropores,while water content increase started in micropores during the freezing-thawing process.The higher the concentration of NaCl solution was,the greater the unfrozen water content was,and the lower the freezing temperature was.Unfrozen water content changed to varying degree in different soils,and the unfrozen water content in the loam was obviously higher than that in the silt loam;saline soil frozen and thawed relatively slowly,and in the areas where freezing and thawing lagged behind obviously,the temperature range tended to decrease with the rising concentration.关键词
盐渍土/未冻水/T2分布/核磁共振/滞后作用Key words
saline soil/unfrozen water/T2 distribution/NMR/hysteresis分类
农业科技引用本文复制引用
卢星航,史海滨,李瑞平,梁建财,徐昭,步怀亮..基于NMR技术的盐渍化冻融土壤未冻水及孔隙水含量试验研究[J].水土保持学报,2017,31(2):111-116,6.基金项目
国家自然科学基金项目(51369018) （51369018）
国家自然科学基金重点项目(51539005) （51539005）
教育部留学回国人员科研启动基金项目([2013]693) （[2013]693）
内蒙古自治区第五批“草原英才”工程项目([2015]56) （[2015]56）
