Evaluating the soil evaporation loss rate in a gravel-sand mulching environment based on stable isotopes data  

作　　者：YANG Ye ZHANG Mingjun ZHANG Yu WANG Shengjie WANG Jiaxin 

机构地区：[1]College of Geography and Environmental Science,Northwest Normal University,Lanzhou 730070,China [2]Key Laboratory of Resource Environment and Sustainable Development of Oasis,Lanzhou 730070,China

出　　处：《Journal of Arid Land》2022年第8期925-939,共15页干旱区科学（英文版）

基　　金：supportedby the National Natural Science Foundation of China(41771035,42071047)。

摘　　要：In order to cope with drought and water shortages,the working people in the arid areas of Northwest China have developed a drought-resistant planting method,namely,gravel-sand mulching,after long-term agricultural practices.To understand the effects of gravel-sand mulching on soil water evaporation,we selected Baifeng peach(Amygdalus persica L.)orchards in Northwest China as the experimental field in 2021.Based on continuously collected soil water stable isotopes data,we evaluated the soil evaporation loss rate in a gravel-sand mulching environment using the line-conditioned excess(lc-excess)coupled Rayleigh fractionation model and Craig-Gordon model.The results show that the average soil water content in the plots with gravel-sand mulching is 1.86%higher than that without gravel-sand mulching.The monthly variation of the soil water content is smaller in the plots with gravel-sand mulching than that without gravel-sand mulching.Moreover,the average lc-excess value in the plots without gravel-sand mulching is smaller.In addition,the soil evaporation loss rate in the plots with gravel-sand mulching is lower than that in the plots without gravel-sand mulching.The lc-excess value was negative for both the plots with and without gravel-sand mulching,and it has good correlation with relative humidity,average temperature,input water content,and soil water content.The effect of gravel-sand mulching on soil evaporation is most prominent in August.Compared with the evaporation data of similar environments in the literature,the lc-excess coupled Rayleigh fractionation model is better.Stable isotopes evidence shows that gravel-sand mulching can effectively reduce soil water evaporation,which provides a theoretical basis for agricultural water management and optimization of water-saving methods in arid areas.

关 键 词：soil evaporation loss rate gravel-sand mulching stable isotopes line-conditioned excess coupled Rayleigh fractionation model Craig-Gordon model 

分 类 号：S152.73[农业科学—土壤学]