全自动真空冷凝抽提系统的检验、优化及应用  

Examination,optimization and application of automatic cryogenic vacuum distillation system

作　　者：简静 文伟 宋欣 JIAN Jing;WEN Wei;SONG Xin(College of Life Sciences and Oceanography,Shenzhen University,Shenzhen 518071,Guangdong Province,P.R.China;Shenzhen Key Laboratory of Marine Biotic Resources and Ecological Environment,Shenzhen University,Shenzhen 518071,Guangdong Province,P.R.China)

机构地区：[1]深圳大学生命与海洋科学学院,广东深圳518071 [2]深圳大学深圳市海洋生物资源与生态环境重点实验室,广东深圳518071

出　　处：《深圳大学学报（理工版）》2023年第2期179-187,共9页Journal of Shenzhen University(Science and Engineering)

基　　金：国家自然科学基金资助项目(42177048);深圳市海外高层次人才资金孔雀团队资助项目(KQTD2017032715165926)。

摘　　要：植物及土壤水分的真空抽提是同位素生态水文研究的核心环节.为验证新一代基于低温真空抽提(cryogenic vacuum distillation,CVD)的水分提取技术——全自动真空冷凝抽提系统的稳定性及可靠性,优化该系统的抽提条件以及探索该系统的应用性,分别利用手动CVD系统与自动CVD系统,对自来水及4种野外采样的木本植物叶片和枝条进行水分抽提后,比较样品水的稳定氢氧同位素比值(δ^(2)H和δ^(18)O);分别利用手动CVD系统与自动CVD系统在不同抽提时长下对浸泡复水的叶片、枝条及土壤样品进行水分抽提后比较样品水δ^(2)H和δ^(18)O;将自动CVD系统作为样品水提取工具,对木樨主要吸水层位及水源水利用比例进行研究.研究结果表明:两种系统对自来水及野外采样的植物抽提后的样品水δ^(2)H和δ^(18)O不存在显著性差异,且样品水同位素间存在与1∶1线无统计差别的强线性关系;自动CVD系统分别对叶片抽提1 h、枝条2h及土壤2 h后样品水的δ^(2)H和δ^(18)O值,与手动CVD进行抽提后的结果无统计学差异,复水后的样品水δ^(2)H较参考水贫化;基于δ^(2)H所确定的木樨吸水层位、水源水利用比例与基于δ^(18)O确定的结果不一致.本研究验证了自动CVD系统与手动CVD系统不存在差异,为该系统支撑同位素生态水文的相关应用提供了重要保障;优化了自动CVD系统抽提时间,提高了抽提效率;同时也发现,CVD系统无法使复水后的植物及土壤样品的δ^(2)H恢复至参考水的δ^(2)H,为生态水文领域近年来揭示的CVD系统存在固有δ^(2)H偏差这一重要现象增添了证据;利用CVD系统抽提后的样品水δ^(2)H于植物水源示踪及利用模式研究时需更加谨慎.Cryogenic extraction of water from plant and soil samples constitutes a critical element in isotope ecohydrological studies.This study was undertaken to examine the stability and reliability of a new generation of water extraction technology based on cryogenic vacuum distillation(CVD)-automatic cryogenic vacuum distillation water extraction system,and to optimize the extraction time and improve the extraction efficiency for this system,as well as to explore the applicability of this system.For these purposes,water extraction from tap water and leaves and stems of four species of woody plants was carried out by using manual and automatic CVD systems and then the hydrogen and oxygen isotope values(δ^(2)H andδ^(18)O)of water extracted from the two systems were compared.Besides,rehydrated leaves,stems and soils were extracted by manual CVD system and automatic CVD system under different extraction time lengths,then theδ^(2)H、δ^(18)O of water extracted with the two systems were compared too.Moreover,we conducted a separate experiment to use the automatic CVD system to confirm the depth of water absorption and the utilization ratio of source water of Osmanthus fragrans(Thunb.)Loureiro.The results are as follows.There is no significant difference in the hydrogen and oxygen isotope values(δ^(2)H,δ^(18)O)of water extracted with the two systems and that data obtained from the two methods are strongly linearly correlated,with the correlation line being statistically indistinguishable from the 1:1 line.Theδ^(2)H andδ^(18)O values of rehydrated sample water extracted from leaves,stems and soils for 1 h,2 h,and 2 h by automatic CVD system are not statistically different from those extracted by manual CVD system.The depth of water uptake and the proportion of water use of Osmanthus fragrans(Thunb.)Loureiro determined based onδ^(2)H is inconsistent with that determined based onδ^(18)O.Therefore,this study systematically verifies for the first time that there is no difference between automatic CVD system and manual CV

关 键 词：植物生态学 稳定同位素 氢同位素 氧同位素 低温真空抽提偏移 自动低温真空抽提系统 植物水源 根系吸水 

分 类 号：Q178.1[生物学—水生生物学]