Dissolved atmospheric gas in xylem sap measured with membrane inlet mass spectrometry.
Dissolved atmospheric gas in xylem sap measured with membrane inlet mass spectrometry.
复制标题
使用膜入口质谱法测量木质部汁液中溶解的大气气体。
DOI：
10.1111/pce.12678
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发表时间：
2016
期刊：
影响因子：
--
通讯作者：
Bradley K. Esser
中科院分区：
文献类型：
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作者：
H. Jochen Schenk;S. Espino;A. Visser;Bradley K. Esser
本文介绍了一种用膜进样质谱法测定小体积木质部汁液中溶解气体浓度的新方法。该技术可用于确定大气气体的浓度，如氩气，如本文所述，或用于各种应用的任何溶解气体及其同位素，如在树木吸收后仅数小时快速检测地下水中的痕量气体和估计生根深度。木质部树液中的大气气体含量直接影响允许从木质部栓塞中去除气体的条件和机制，因为气体只有在高于大气压的气体压力下才能溶解到饱和或过饱和树液中。该方法进行了测试，红喇叭藤，Distictis buccinatoria（Bignoniaceae），通过测量收集在最低和最高日温度的时候，在温度上升和下降的汁液中的大气气体浓度。平均氩浓度在木质部汁液中没有显着不同的温度和压力条件下的饱和度在任何时候收集，但超过40%的所有样品过饱和，特别是在温暖的一天的部分。由于样品之间的高变异性，没有显著的昼夜模式。
A new method is described for measuring dissolved gas concentrations in small volumes of xylem sap using membrane inlet mass spectrometry. The technique can be used to determine concentrations of atmospheric gases, such as argon, as reported here, or for any dissolved gases and their isotopes for a variety of applications, such as rapid detection of trace gases from groundwater only hours after they were taken up by trees and rooting depth estimation. Atmospheric gas content in xylem sap directly affects the conditions and mechanisms that allow for gas removal from xylem embolisms, because gas can dissolve into saturated or supersaturated sap only under gas pressure that is above atmospheric pressure. The method was tested for red trumpet vine, Distictis buccinatoria (Bignoniaceae), by measuring atmospheric gas concentrations in sap collected at times of minimum and maximum daily temperature and during temperature increase and decline. Mean argon concentration in xylem sap did not differ significantly from saturation levels for the temperature and pressure conditions at any time of collection, but more than 40% of all samples were supersaturated, especially during the warm parts of day. There was no significant diurnal pattern, due to high variability between samples.