气生植物的生物学特性及研究展望

气生植物是指不需要土壤，生长所需的水分和营养可以全部来自空气的植物。它既不同于附生植物．也不同于具有气生根的植物。主要包括地衣、苔藓、蕨、凤梨科和兰科植物中的某些附生类群。它们没有根或者根不发达，仅起固定植株的作用。因为气生植物直接从空气中吸收水分和养分，但空气中的水分和养分毕竞是有限的，所以这些植物一般都具有很强的利用水分及养分的能力，很多植物已经成为有效地检测环境变化的“指示生物”和去除环境污染的修复植物。另外，因为这些植物具有忍受恶劣环境条件的生理基础，还可能成为适应空间环境的先锋植物，在空间植物学研究中将具有特殊的意义。

Advances in biological characters of air plants

Air plant is a type of plant that grows on rocks, trees, shrubs etc. without soil. Unlike other plants, their roots are not used for absorbing water and nutrients but serve only as anchors to attach to trees or rocks. Some epiphytic plants of lichen, moss, fern, Bromeliaceae and Orchidaceae are the main air plants. They receive all of their water and nutrients directly from the air through specialized Leaves. For this reason they have high water and nutrient use efficiency, and were selected to carried out monitoring study of air pollution. In addition, they are probably to be the pioneering plants in space environment because they are able to bear various stresses.