地衣的妙用

The Marvelous Lichen

本刊曾在2000年第4期刊登过一篇“地衣之歌”,作者别具匠心,以诗歌形式向读者介绍了关于地衣的知识,流畅的诗句和通俗易懂的内容至今让人回味。这里我们摘录了“地衣之歌”的部分内容,连同作者拍摄到的一组珍贵的有关地衣的照片和“地衣的妙用”一文再次献给读者。

Lichens form an important component of biological diversity and resources. Approximately 14,000 species of lichens are known from throughout the world, and about 2,000 lichen species are known from China. However, what is a lichen? The recognition of the actual nature of lichens has an interesting history.In Linnaeus's time lichens were considered to be a single plant and included in the same order as mosses and algae. Schwender (1867) in Germany discovered the dual nature of lichen, showing them to be a composite organism containing both a fungus and an alga rather than being a single green plant. Vainio (1890) in Finland was the first to propose that lichens be included in fungi. Therefore, based on current concepts, a lichen is a considered a symbiotic association of a fungus and an alga resulting in a stable thallus of specific structure. In systematic terms, such a fungus which forms a constant and definite association with an alga, is called a lichenized fungus. The scientific name of a lichen refers to that of the fungus in the symbiotic association. Approximately 97% of lichen species belong to the Ascomycota. The composition of lichens, their diversity, phytochemistry. habitats, important characters, scientific and applied uses are introduced in the 'Song for Lichens', which is the first attempt to disperse scientific knowledge about lichens in poetic form.