摘要
于2009年8～10月,在辽河口芦苇(Phragmites australis)沼泽地,采用野外培养箱土培模拟实验方法,人为控制水位,用PM-5型稳态气孔计测量了不同水深条件下芦苇叶片的蒸腾速率,研究了芦苇叶片蒸腾及其与影响因子的关系。结果表明,不同水深条件下,芦苇叶片蒸腾速率日变化差异明显;当控制水位在地表以上10cm时,芦苇叶片蒸腾速率曲线呈单峰型,而且芦苇叶片蒸腾作用随着栽培时间的延长受到抑制;当水位在地表以下5cm、20cm、40cm和60cm时,芦苇叶片蒸腾速率变化曲线呈双峰型,并出现明显的"午休"现象;当控制水位在地表以下20cm时,芦苇叶片蒸腾速率最大,当控制水位在地表以下60cm时,其最小。芦苇叶片气孔导度曲线和蒸腾速率曲线变化规律相似,蒸腾速率和气孔导度日变化有显著的相关性。芦苇叶片蒸腾速率受环境因子的影响,当控制水位在地表以上10cm时,芦苇叶片蒸腾速率受光合有效辐射的影响较大;当控制水位在地表以下时,相对湿度是影响芦苇叶片蒸腾速率的主要因子。
The objective of this study is to analysis the transpiration characteristics of Phragmites australis leaf and the relationships between the leaf transpiration and influence factors at different water levels, and to improve plant water use efficient and provide a theoretical basis of ecological water requirement of plant. The simulation experiment was done by containers with Phragmites australis leaf in the field of Liaohe Estuary in August-October 2009.The water levels were controlled and the transpiration rate of Phragmites australis leaf was measured by a portable steady-state porometer （PM-5）. The results showed that the diurnal courses of the transpiration rates of Phragmites australis leaf were different for different water depths. The diurnal courses of the leaf transpiration rate all displayed a single peak pattern when the water depth was 10 cm above soil surface, there was no noon break which was caused by the close of stoma. The peak of the leaf transpiration rate occurred at about 14.＇00. The leaf transpiration rate decreased if Phragmites australis were submerged in water for a long time. When the levels of the grounder water were 5 cm, 20 cm, 40 cm and 60 cm under soil surface, the diurnal courses of the leaf transpiration rate displayed a double peak pattern, there were lower values at 11 ： 00-13 ： 00 resulted from the close of stoma. At the same period there was a maximum value of the leaf transpiration rate when the water level was 20 cm under soil surface. There was a similarity in the variation curve of the leaf transpiration rate and stomatal conductance with good correlation in the study. The leaf transpiration rate of Phragmites australis was affected by photosynthetic active radiation and relative humidity, and the latter was the main factor at different ground water depths.
出处
《湿地科学》
CSCD
2011年第3期227-232,共6页
Wetland Science
基金
国家“水专项”项目(2008ZX07208-009)资助
关键词
湿地
模拟实验
芦苇叶片
蒸腾速率
稳态气孔计
wetland
simulation experiment
Phragmites australis leaf
transpiration rate
portable steady-state porometer
作者简介
作者简介：张颖（1979-），女，山东省胶州人，博士，主要从事水土保持、流域水土污染和生态需水研究。E-mail：zhangyingqd@yahoo．cn
通讯作者：郑西来，教授。E—mail：zhxl@ore．edu．cn
