摘要
【目的】研究辐射与低温水入渗条件下土壤水分和温度特性的变化规律,为进一步研究如何改善水库下游河岸带生态环境提供理论基础。【方法】以中细砂为代表性土样,利用自主研制的试验系统装置,设置3种辐射温度(无辐射、30和40℃),分析了在低温水入渗(水温10℃、入渗水头25cm)和不同辐射温度作用下土壤内部水分和温度的动态变化特性。【结果】砂土湿润锋的垂直距离和稳定入渗率随辐射温度的升高而增加。辐射热流增加,土壤表层温度升高,温度梯度增大,表面向内部的传热量增加,土壤内部温度升高;辐射温度为40℃时,土壤内部温度梯度大,且整体平均温度较无辐射时要高。有无辐射热流,低温水的入渗均会对土壤内部温度和水分分布产生影响,且土壤深层温度降幅较大。有辐射时,土壤表层温度明显高于无辐射。【结论】在低温水入渗条件下,辐射温度的变化对土壤水、热动态均会造成影响,其影响范围和强度因辐射温度的不同而存在差异。
【Objective】This study investigated the variation of soil moisture and temperature affected by radiation and infitration of low-temperature water to support further research on improving downstream ecological environment in the riparian zone.【Method】Using fine sand as the representative soil sample,a self-developed test system device was used to analyze the dynamic characteristics of the soil internal temperature and moisture under infiltration of water at low temperature （water temperature 10 ℃,infiltration head 25 cm） and different radiation temperatures （no radiation,30 and 40 ℃）.【Result】The vertical distance of sandy soil wetting front and steady infiltration rate increased along with the radiation temperature.As the increase of radiation heat flux,the soil surface temperature and temperature gradient rose,and the surface to the internal heat transfer increased accordingly,leading to increase of soil internal temperature.The internal soil temperature gradient was large when the radiation temperature was 40 ℃,and the overall average temperature was higher than that of no radiation.The infiltration of water at low temperature had impacts on the soil internal temperature and moisture distribution regardless radiation.And the reduced amplitude of temperature in deep soil was large.Soil surface temperature with radiation was significantly higher than the case without radiation.【Conclusion】With low water infiltration,variation of radiation temperature had influence on soil moisture and temperature dynamics,and its scope and impact strength varied with radiation temperature.
出处
《西北农林科技大学学报（自然科学版）》
CSCD
北大核心
2014年第4期150-156,共7页
Journal of Northwest A&F University(Natural Science Edition)
基金
国家自然科学基金项目(51309189)
关键词
辐射
低温水
入渗
土壤水分
土壤温度
radiation
low-temperature water
infiltration
soil moisture
soil temperature
