文献类型：期刊文献

中文题名：不同降水条件下两种荒漠植物的水分利用策略

英文题名：Water-use strategies of two desert plants along a precipitation gradient in northwestern China

作者：周雅聃[1,2] 陈世苹[1] 宋维民[1,2] 卢琦[3] 林光辉[1,4]

第一作者：周雅聃

机构：[1]中国科学院植物研究所植被与环境变化国家重点实验室;[2]中国科学院研究生院;[3]中国林业科学研究院荒漠化研究所;[4]清华大学地球系统科学研究中心

年份：2011

卷号：35

期号：8

起止页码：789-800

中文期刊名：植物生态学报

外文期刊名：Chinese Journal of Plant Ecology

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

基金：中国林业科学研究院院长基金(CAFYBB-2007008);国家基础研究发展规划(973)项目(2010-CB833501);国家自然科学基金青年基金(30800-141)资助

语种：中文

中文关键词：干旱、半干旱地区;油蒿;IsoSource模型;白刺;脯氨酸;稳定同位素;水分利用效率

外文关键词：arid and semiarid region; Artemisia ordosica; IsoSource model; Nitraria tangutorum; proline; stable isotope; water use efficiency

分类号：Q948.44

摘要：自然降水是干旱、半干旱地区荒漠植物重要的水分来源。为了说明自然降水量的变化对干旱、半干旱地区荒漠植物水分利用策略的影响,研究了两种常见荒漠植物油蒿(Artemisia ordosica)和白刺(Nitrariata ngutorum)在3个不同自然降水地区(内蒙古的杭锦旗和磴口县及甘肃的民勤县)的水分来源、水分利用效率及植物的抗逆能力的变化。测定了不同地区的植物茎水、各潜在水源(降水、地下水和土壤水)的δD和δ18O值,并利用IsoSource模型分析了这两种植物在不同地区对这些潜在水源的选择性利用情况;同时测定了叶片的δ13C和游离脯氨酸浓度。结果表明:在年降水量最高的杭锦旗,这两种植物对浅层土壤水的利用比例最高,其中油蒿主要利用0–50cm土层中的水源;在年降水量相对较低的磴口和民勤,植物利用的主要水源为深层土壤水和地下水。随着年降水量的增加,这两种植物的水分利用效率逐渐降低。白刺的脯氨酸浓度大于油蒿,与水分利用效率无关,但油蒿的水分利用效率和脯氨酸浓度成正比。研究表明,荒漠植物能通过改变其水分利用策略和其他生理特性适应自然降水量的变化,但不同植物种采用的策略可能有所不同。
Aims In arid and semiarid regions, precipitation is the most important water source for plants. Our objective was to investigate the water-use strategies of two dominant desert plants along a precipitation gradient in northwestern China. Methods We determined stable hydrogen and oxygen isotope compositions of the stem water from Artemisia ordosica and Nitraria tangutorum and potential water sources （rain water, groundwater and soil water） at three study sites with different annual precipitation （Hanggin Banner and Dengkou County of Inner Mongolia Autono-mous Region and Minqin County of Gansu Province）. The IsoSource model was then used to calculate probable contributions of potential water sources to total plant water uptake. We also determined foliar carbon isotope ratios and free proline contents of both species to indicate water use efficiency and osmotic-adjustment ability. Important findings At the Hanggin Banner site （highest annual precipitation）, both species obtained the highest proportion of water from shallow soil water and A.ordosica took up water mostly from the 0–50 cm soil layer. However,they depended mainly on deep soil water or groundwater at the Dengkou and Minqin sites with lower annual precipitation. The water use efficiency of both species decreased with increasing annual precipitation. There was a positive correlation between carbon isotope ratio and free proline content in A.ordosica. These re-sults suggest that desert plants can adjust their capabilities for up-take from different water sources and other physiological properties with variation in natural precipitation, but the strategies are species-specific.