不同生境下入侵种假臭草叶片的气孔特征

【背景】探讨入侵种假臭草不同生境下气孔的变化规律，揭示假臭草种群在不同生境下所采取的生长对策及适应机制，可为入侵生物的防治提供参考。【方法】采取光学显微镜系统观察桉树林、木薯地、弃耕地、公路边4种生境下假臭草叶片的气孔特征。【结果】光照和土壤肥、水条件对假臭草叶片的气孔孔径（横轴方向和纵轴方向）、单个气孔器面积、气孔器总面积、气孔密度及气孔指数的影响显著。低光照及肥沃、湿润土壤生境与高光照及贫瘠、干旱土壤相比，假臭草的气孔孔径（横轴方向和纵轴方向）、单个气孔器面积、气孔器总面积较大，气孔密度及气孔指数较小。【结论与意义】假臭草叶片气孔特征表现可塑性，说明其对异质环境具有一定的生态适应能力。

Analysis on the stomatal characteristics of Eupatoriun catarium (Compositae) under different habitat conditions

Background]The purpose of this research was to study the variation of the stomatal characteristics of Eupatorium catari um in different habitats, and to reveal the growth strategies and adaptation mechanisms in different habitats, so as to provide theoret ical information for the control of this invasive plant. Method] Optical microscopy was used to observe the stomatal characteristics of E. catarium in collected from eucalyptus forest, cassava field, wasteland and roadsides. Result ] Light and soil nutrients had a sig nificant influence on the stomatal aperture （the horizontal axis and vertical axis） , single stomatal area, total stomatal area, stomatal density and stomatal index. E. catarium in lowlight but high soil water and nutrient conditions had larger stomatal aperture, single and total stomatal areas, but displayed smaller stomatal density and stomatal index, while in highfight but low soil water and nutri ent conditions, the opposite was observed： smaller stomata1 aperture, single and total stomatal area, but larger stomatal density and stomatal index. Conclusion and significance]These stomatal characteristics indicate that E. catarium possesses a certain ecological adaptability to heterogeneous environments.