Economic Importance of Lichens – An Overview | Lichenology

In this article we will discuss about economic importance of lichens

Economic Importance of Lichens

• Lichens are symbiotic association with fungi and algae.
• They hold considerable significance in the economy and are contribute to various industries.
• The economic importance of lichens can be categorized into two main parts: beneficial aspects and harmful aspects.
• Beneficial Aspects: Lichens as food, lichens as fodder, medicinal use, industry, pioneer colonizers and indicators of pollution
• Harmful Aspects: Harmful to plants, cause forest fires and damage man made structures etc.

1. Lichens as Food

• Lichens used as food because they are rich in polysaccharides, vitamins and some enzymes.
• Cetraria islandica (Iceland moss) is consumed in Norway, Sweden, Iceland and other Scandinavian countries.
• Various species of Parmelia (Rock flower) are used for curry preparation in India.
• Evernia prunastri was used as baking powder by the Egyptians.
• In France, lichens are used for making chocolates and pastries.
• Lecanora esculenta (Manna lichen) is consumed by desert tribes in Asia Minor.

2. Lichens as Fodder

• Lichens such as Lobaria pulmonaria, Evernia prunastri, Ramalina fraxinea, and R. fastigiata are utilized as fodder for cattle.
• Cladonia rangiferina (Reindeer Moss) are used as fodder for musk oxen, caribou, reindeer, and various wild animals.
• Cetraria islandica (Iceland moss) is used as fodder for horses.
• Numerous animals including mites, caterpillars, termites, snails, and slugs are partially or entirely depends on lichens for their diet.

3. Medicinal Use

• Some lichens used in traditional medicine to treat fever, jaundice, skin diseases, epilepsy etc.
• A mucilaginous substance extract from Cetraria islandica is used as a laxative.
• Protolochesterinic acid, obtained from select lichens, is utilized in the formulation of anti-cancer medications.
• Rocella montagnei is used to treat angina (Chest pain).

4. Industrial Uses

• Various types of lichens used across multiple industries.
• Orchil, a blue dye derived from Roccella and Lecanora, is used for dyeing woolen products and silk textiles.
• Litmus, another widely used dye in chemical laboratories, serves as an acid-base indicator and is obtained from Rocella montagnei.
• Lichens such as Lobaria pulmonaria are used in the brewing industries (Beer making)
• In Russia and Sweden, the Usnea florida, Cladonia rangiferina and Ramalina fraxinea are used in alcohol production due to their high content of lichenin, a carbohydrate.
• Lecanora esculenta, found in limestone deserts, produces significant amounts of calcium oxalate crystals.
• Evernia, Ramalina, and Pseudorina are contain fragrant volatile oils, which are used to various cosmetic products, perfumes, and incense materials.

5. Pioneer colonizers

• Lichens are recognized as pioneers in the establishment of vegetation on bare rocky surfaces.
• They are the initial organisms to colonize the barren rocky area.
• Throughout their growth, lichens contribute to the disintegration of rock (biological weathering) by producing acids such as oxalic and carbonic acid.
• They play important role in nature by facilitating soil formation, a process known as pedogenesis.

6. Indicators of Pollution

• Lichens are very sensitivity to pollution. So, they can be used as indicators of pollution.
• They re very much sensitive to various air pollutants like sulfur dioxide (SO2), carbon monoxide (CO), and carbon dioxide (CO2).
• After industrialization, numerous lichen species have become extinct in many areas of Britain. E.g., Usnea articulata.
• Lichens are easily affected by sulphur dioxide because the algal partner in them suffer from loss of chlorophyll and reduced photosynthesis.
• The shrubby and leafy lichens are the most sensitive to pollution, while crustose lichens has greater tolerance.
• Lichens possess the ability to absorb water and mineral nutrients through their surface. So, they readily absorb a wide variety of toxic substances.
• One of the ways lichens directly help humans by absorbing various substances from the air, particularly pollutants.
• Heavy metals, carbon, sulfur, and other pollutants present in the air are absorbed into the lichen thallus.
• Researchers can extract those toxins and determine the levels of air pollution in specific areas.