Lichen as bioindicat​or

 

 

Lichen as bioindicat​or: keeping in view of the ongoing climatic variation, it is very demanding to study the lichen distribution as they are the key bioindicators in an ecosystem. The lichens are very less tolerant to pollution load and immediately they respond to any kind of stress by their presence and absence. The crustose lichens tolerate the maximum pollution load where as both foliose and fructicose lichens do the least. As Lichen diversity is maximum in Sal tree (Shorea robusta) which harbours almoast 64 species followed by Mango (Mangifera indica) and Sindur (Mallotus philipensis) and these are very common tree in almost all part of India, one can easily observe the type of epiphytic lichens growing there to study the dynamics of pollution load in their respective local ambience by the presence/absence and appearance/vanishing of lichens without any chemical analysis. Elimination of large number of lichen species in an area is an indicator of growing environmental pollution, as lichen cannot tolerate the acidic gases. Thus in areas with high acidic gases, a few resistant species will occur. The pollution-tolerant species exhibit aggressive behaviour spreading rapidly, covering a variety of substrates. I have collected 45 species of lichens from different parts of Orissa as epiphytes on Sal tree which are varrying in their diversity and distribution. Thus the number and distribution of lichen species on Shorea robusta can be utilized as indicator species for carrying out rapid future biomonitoring studies in the area.

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