Lichen: neglected pioneer, what are the benefits of lichen?

Lichen is not a single organism. On the contrary, it is a symbiotic relationship between different organisms-fungi and algae or cyanobacteria. Cyanobacteria are sometimes called "blue-green algae", although they are very different from algae. Non-fungal chaperones contain chlorophyll and are called photobiological agents. Fungal chaperones can be called lichen symbionts. Although most lichen partners consist of a fungal organism and a photoorganism, this is not common because lichens have more than one photoorganism partner. Under the microscope, we can see that the chaperone molecules of fungi are composed of filamentous cells, and each filamentous cell is called mycelium. These hyphae grow by extension and can branch but keep the same diameter.

In photoorganisms, some are also filamentous, while others are composed of more or less spherical chains or cell clusters. Because algae and cyanobacteria contain chlorophyll, they can make carbohydrates through a process called photosynthesis with the help of light. In contrast, fungi can't make carbohydrates by themselves. Every fungus needs existing organic matter to obtain carbon. In lichens, some carbohydrates produced by photosynthesis are of course utilized by photosynthesis, but some are also "harvested" by fungi. Lichens grow on almost all land, from ice-free polar regions to tropical regions, from tropical rainforests to desert regions without moving dunes.

Although some aquatic lichens are widely known on land. The growth environment of lichen on the surface (or substrate) ranges from natural environment (such as soil, rock, wood and bones) to artificial environment (asphalt, concrete, glass, canvas and metal, and so on). The structure of lichen was not formed by either side. When fungi or photoorganisms are cultured alone, the chemicals they produce usually do not exist, so lichens are not just the sum of their parts. In fact, lichens can synthesize more than 800 substances, many of which are not found in nature.

Although lichen fungi do not appear as independent organisms in nature, many photosynthetic organisms can exist in the form of free life. These two partners can grow separately in the laboratory, but it is very difficult to synthesize lichens. When fungi and photoorganisms are under pressure (for example, by lowering the level of water and nutrition), they can succeed, which shows that lichen partnership was first formed to overcome adversity. Lichens not only have important ecological functions, but also are used as food, medicine and dyeing cloth by human beings. For example, cloth is traditionally used to make the color of Harris tweed.