Ecological, Social and Commercial Role of Lichens in India with ...

Acdemia Arena 2010, Supplement 0201
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Lichens have ability to resist extremes of climatic conditions ranging from low tide sea
shores to the tops of the mountains and from arctic to tropical regions, dominating as much as 8%
of the earth’s surface (Ahmadjian 1993; 1995) and are amongst the most significant indicators of
air pollution and ecosystem health (Richardson 1992) and, besides having many economic
medicinal applications. They are very sensitive to microclimatic changes. Therefore any natural
manmade disturbances are bound to affect lichen populations. Requisite moisture and light,
unpolluted air and undisturbed substratum often favour optimum growth and abundance of lichens.
Lichens arbitrarily classified into three to seven growth forms that do not reflect how the lichens
are related to each other. Different species within a genus may have different growth forms viz 1.
Crustose, 2. Foliose, 3. Fruticose and 4. Squamulose. Crustose lichens form crusts that are so
tightly attached to the rocks, trees, side walls or soils they grow on that they cannot remove without
damaging the substrate. Cracked crusts like the species of Acarospora that are separated into
segments (areoles) are called areolate. Crustose lichens, that grows immersed in rocks only their
fruiting bodies above the surface are called endolithic, and those that grow immersed in plant
tissues are called endophloidic or endophlodal. Loose, powdery lichen crusts without a layered
structure called leprose lichens. Foliose lichens are somewhat leaf-like, composed of lobes. They
are relatively loosely attached to their substrates, usually by means rhizines. Their lobes have upper
and lower sides and usually grow more or less parallel to the substrate viz. Lobaria. Fruticose
lichens are usually round in cross section and most are branched. They can like little shrubs
growing upward, or they can hang down in long strands viz. Usnea longissima.
Lichens in Indian Languages
In Indian context, the Sanskrit synonyms of lichens are ‘Shailaya’ and ‘Shila Pushp’ meaning
Shila=rock Pushp=flower. Lichen species are commonly known ‘Stone flower’ in English, ‘Pathar
Ka Phul’ in Hindi, ‘Dagad Phul’ in Marathi, ‘Kalahu’ in Kanada, ‘Kalpasi’ in Tamil, and
‘Rihamkarmani’ in Urdu. Locally in Garhwal it is known as ‘Mukku’, ‘Shewal’, ‘Jhoola’;
‘Chaarila’ in Kumaun; ‘Chaai’ and ‘Mendi’ in Himanchal. In Hindi the lichens are also known as
‘Shaik’ (meaning Shai= Shewal and K= Kawak).
India ranks amongst one of the twelve-mega-biodiversity countries of the world. The
innumerable life forms from unicellular to multicellular and microscopic to gigantic harboured in
the forests, deserts, mountains, other land forms and air and water. They are source of food, fuel,
clothing and various others our daily needs and raw material for industries.
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