文献类型：期刊文献

中文题名：利用氘同位素研究太行山南麓枣树水分利用的季节性变化

英文题名：Seasonal Variation in Water Use of Ziziphus jujuba in the South Aspect of Taihang Mountains with Deuterium Isotope Signature

作者：孙守家[1] 孟平[1] 张劲松[1] 万贤崇[2]

第一作者：孙守家

机构：[1]中国林业科学研究院林业研究所国家林业局林木培育重点实验室;[2]中国林业科学研究院林业新技术研究所

年份：2011

卷号：47

期号：5

起止页码：46-53

中文期刊名：林业科学

外文期刊名：Scientia Silvae Sinicae

收录：CSTPCD;;Scopus;北大核心:【北大核心2008】；CSCD:【CSCD2011_2012】；

基金："十二五"国家科技支撑计划课题(2011BAD38B02);林业公益性行业科研专项课题(201104009-04)

语种：中文

中文关键词：枣树;氘同位素;水分来源;枝条栓塞;蒸腾

外文关键词：Ziziphus jujuba; deuterium isotope; water source; branch embolism; transpiration

分类号：S718.43

摘要：通过测定水中氘同位素的比值来研究枣树在不同水分条件下水分利用的季节性变化。试验结果显示:深层土壤δD值比较稳定,表层土壤水因蒸发而产生氢同位素的分馏,氘同位素富集,旱季表层土壤δD值与土壤含水量呈极显著负相关(R2=0.69,P<0.01)。枣树枝条δD值与表层土壤δD值呈极显著的正相关(R2=0.75,P<0.01),与深层土壤δD值相关性不强,表明来源于表层土壤的水分能显著地影响到枝条δD值变化。雨季的降水不但增加表层土壤水分含量,也促使表层新根的生长。其根长比旱季增加621.46%,尤其是细根(平均直径0.16mm),从而提高根系对表层土壤水分的吸收。枣树枝条中的水分有一半以上来自于深层土壤,表层土壤水分的贡献决定枣树体内的水分平衡和受胁迫的程度。枝条中的δD值与枝条栓塞程度、叶片水势和光合速率显著相关,枝条δD值可以作为水分生理状态的一个指标。利用枝条δD值来量化植物水分欠缺程度,可以为植物水分利用效率研究提供参考。
Stable hydrogen isotope composition can be used to trace water source and use in plants.In this experiment,deuterium ratio in water was used to study seasonal variation in water use of Ziziphus jujuba in different environmental water regimes.Results showed that δD value of water in deep soil layers remained steady while δD value in upper soil layers had a significant variation over seasons because deuterium isotope was fractionated during evaporation.Deuterium isotope was enriched and δD value increased in the shallow soil.There was a significantly negative correlation（R2 = 0.69,P 0.01） between the δD value and water content in the shallow soil layers in dry season.δD value of branch xylem water was significantly and positively correlated（R2 = 0.75,P 0.01） with the water content in shallow soil but not with that in deep soil.The results indicated δD value of branch xylem water was heavily influenced by water in shallow soil.Precipitation increased water content of shallow soil layers in wet season,which promoted new root growth in the shallow soil.New root length in the shallow soil increased by 621.46% in wet season than that in dry season.Most of the new roots were fine roots and the average diameter was 0.16 mm.The increased fine root was able to enhance water uptake from the shallow soil.Over 50% of the xylem water of Z.jujuba branch were extracted from the deep soil layers,especially in dry season.However,the contribution of shallow soil water significantly affected the water balance and stress degree in Z.jujuba.Data analyses showed δD value of water in the branch xylem was strongly correlated with branch embolism,predawn leaf water potential and photosynthesis rate.The results suggested that δD value of xylem water could be used as an indicator of the plant water status.Quantification of drought stress of plants with δD value would provide a credible reference in studying water use efficiency of plants.