石漠化区朴树叶片结构与蒸腾量的相关性探讨

以石漠化区不同胸径朴树叶片为试验材料,利用针式热脉冲树干液流仪监测日蒸腾耗水量的变化,利用FAA固定切片法观测叶片海绵组织厚度、栅栏组织厚度、维管束粗度及木质部厚度等解剖结构。发现影响不同季节不同胸径朴树平均日耗水量的主要因素为叶片的栅栏组织厚度和海绵组织厚度。栅栏组织厚度与平均日耗水量呈正相关关系,而栅栏海绵组织厚度与平均日耗水量呈负相关关系。在不同胸径朴树中,旱季的平均日耗水量大小顺序为7.1 cm胸径朴树﹥6.3 cm胸径朴树﹥8.5 cm胸径朴树,结果表明在石漠化区长期的进化过程中,较大胸径朴树能更好的适应干旱的环境。

Study on the correlation between leaf structure and transpiration of Celtis sinensis Pers.in rocky desertification area

In this paper,the changes of average daily transpiration water consumption were monitored by the needle pulsed trunk fluid flowmeter,while the sponge tissue,palisade tissue,vascular bundle,and xylem thickness of leaves were observed by the FAA fixed section method.It was found that the main factors affecting the average daily water consumption of Celtis sinensis Pers.with different DBH in different seasons were palisade tissue and sponge tissue thickness.The thickness of palisade tissue was positively correlated with the average daily water consumption,while the thickness of sponge tissue was negatively correlated with the average daily water consumption.In different DBH,the average daily water consumption of Celtis sinensis Pers.in dry season was ordered as following:7.1 cm>6.3 cm>8.5 cm,indicating that Celtis sinensis Pers.with larger DBH can adapt to the arid environment better in the long-term evolution of rocky desertification areas.