干旱区荒漠植物体内潜在水源差异及利用策略分析  

Analysis of Potential Water Source Differences and Utilization Strategies of Desert Plants in Arid Regions

作　　者：李文静 吕光辉[1,2] 张磊 王恒方[1,2] 李周康 王金龙 马辉英 刘志东[1,2] LI Wenjing;LV Guanghui;ZHANG Lei;WANG Hengfang;LI Zhoukang;WANG Jinlong;MA Huiying;LIU Zhidong(College of Resources and Environmental Science,Xinjiang University,Urumqi 830046,China;Key Laboratory of Oasis Ecology,Ministry of Education,Urumqi 830046,China)

机构地区：[1]新疆大学资源与环境科学学院,新疆乌鲁木齐830046 [2]绿洲生态教育部重点实验室,新疆乌鲁木齐830046

出　　处：《生态环境学报》2019年第8期1557-1566,共10页Ecology and Environmental Sciences

基　　金：国家自然科学基金项目(41571034)

摘　　要：水作为干旱区重要的环境因素之一,是荒漠植物生长发育的主要限制因子,故在荒漠区开展植物体内潜在水源差异及水分利用策略分析对综合理解生态水文过程具有重要意义。通过对艾比湖流域不同生活型荒漠植物的木质部及潜在水源(凝结水、地下水、河水和土壤水(0-40、40-70、70-100、100-150 cm))的稳定同位素值(δ18O)进行统计学分析,利用多源线性混合模型(IsoSource)分析各潜在水源对植物体所吸收利用水分来源的贡献比率,并比较各潜在水源之间δ^18O值。结果表明,(1)土壤水的δ^18O变化范围为(-6.292‰--3.995‰),并且δ18O随着土壤深度的加深,不同土层间的δ^18O表现为逐渐偏负;乔灌木与草本的δ18O差异显著,而乔木与灌木的δ^18O差异不显著。(2)不同生活型的植物在对水分来源上存在明显差异,乔木对水分的利用主要集中于单一地下水资源;灌木除较多利用地下水外,也多元的利用其它水源;芦苇(Phragmites australis)与盐生草(Halogeton glomeratus)主要利用地下水,其它草本植物将表层土壤水作为首要水源。(3)浅根系与中深根系植物在各水源利用方面,除对(100-150 cm)的土壤水的利用无显著差异外,对其它水源利用均存在极显著差异(P<0.01)。在根系类型上表现出明显的垂直分布规律:中深根系植物将地下水作为第一水源,而浅根系植物主要利用表层土壤水(0-40 cm)。以上研究结果表明,干旱荒漠区,植物所需水分主要受生活型和根系类型影响,其中后者影响更甚。As an important environmental factor in arid areas,water is a major limiting factor for the growth and development of desert plants.Therefore,it is of great significance to develop potential water source differences and utilization strategies in desert areas for the comprehensive understanding of ecological and hydrological processes.In present study,the stable isotope values(δ^18O)was measured in the xylem of desert plants with various life forms and their potential water sources(condensate water,groundwater,river water and soil water)in the Ebinur lake basin.We then,analyzed the contribution ratio of each potential water source to the water absorbed by the plant using multi-source linear mixed models(IsoSource),and compared theδ18O values between potential water sources.The results show that:(1)Theδ18O ranges from-6.292‰to-3.995‰in the soil water,and with the increase of soil layer depth,theδ^18O gradually decreases.Theδ^18O is not significantly differentiated between trees and shrubs,but both of them significantly differ with herbs.(2)Plant of different life form have significant difference in utilization of water source.The groundwater is the exclusive water source for trees;For shrubs,the groundwater is the primary water source,but they also use other water sources in multiple ways;Phragmites australis and Halogeton glomeratus mainly make use of groundwater,while other herbaceous plants primarily utilize surface soil water.(3)The shallow root system and medium-deep root plants have significant difference(P<0.01)in the utilization of soil water in different layers except for the 100?150 cm layer.A clear vertical spatial pattern of water absorption is observed regarding root system:medium-deep root plants mainly using groundwater,while shallow root plants mainly using surface soil water(0?40 cm).These results demonstrate that the water requirement of plants in desert areas is mainly influenced by their life form and root type,in which the effects of the root type is more outstanding.

关 键 词：艾比湖流域 水分来源 荒漠植物 生活型 根系类型 冠层凝结水 

分 类 号：Q945.78[生物学—植物学] Q945.79