Application of Hydrogen and Oxygen Stable Isotopes for Determining Water Sources Used by Cotton in Xinjiang Arid Region
Li Hui
Liang Xing
Liu Yanfeng
Liu Yalei
Xian Yang
Abstract：Cotton is the main crop in arid areas of Northwest China.Study on the water sources of crops is of great significance to make proper irrigation schedules and realize agricultural water-saving irrigation in arid regions.In this study,precipitation,irrigation water,soil water and cotton stem water were sampled for stable isotope analysis in the Paotai Soil Improvement Test Station in Xinjiang Production and Construction Corps.Based on the stable hydrogen and oxygen isotopic tracing method and hydrological observations,the dynamic variation of stable isotope values in soil water under mulched drip irrigation was analyzed to determine the water sources of the cotton in different growth stages and the sources after irrigation pulse.The contributions of soil water at different depths to cotton water uptake were quantified by the IsoSource model.Results show that the main uptake depth of soil water in bud stage,blooming stage,boll stage and open boll stage are distributed in 0 to 30 cm layer (78.2％),30 to 60 cm layer(31.9％),60 to 110 cm layer(32％)and 110 to 220 cm(47.3％),respectively.The main sources of water used by cotton gradually increase with the advance of growth stage.Cotton adjusts rapidly water sources after mulched drip irrigation,by significantly increasing the proportions of water use in 0 to 30 cm soil.The results also indicate that the proper irrigation schedule with low irrigation volume and high irrigation frequency can improve the utilization efficiency of irrigation water in arid regions.
Keywords：hydrogen and oxygen stable isotopeswater useIsoSource modelcottonarid regionhydrogeology
Publication Date：2017-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：10( 843-852 )