HABIT AND HABITATS

Pteridophytes grow luxuriantly in moist tropical forests and temperate forests and their occurrence in different eco-geographically threatened regions from sea level to the highest mountains are of much interest (Dixit, 2000). Though they have been largely replaced by the seed plants in the modern day flora, they continue to occupy an important and crucial position in the evolutionary history of the plant kingdom. India has a rich and varied pteridophytic flora due to its originduring the break-up of the Gondwanaland, its drift from south of the Equator towards Eurasia far north, carrying the progenitors of today’s pteridophytes from Australia, Africa, Madagascar etc. as well as probable endemics of its own and after joining with Eurasia its diversified topography, variable climatic conditions and its strategic geographical position facilitated several migration-flows of species of different phytogeographical elements meeting in different parts of the Country. They occur today in a variety of habit like terrestrial (Equisetum, Selaginella), aquatic (Azolla, Marsilea), epiphytic (Lepisorus, Drynaria) and lithophytic (Psilotum, Adiantum).Today, among the vascular plants, pteridophytes form a major part next only to the angiosperms in India.

The pteridophytes themselves do not constitute any major vegetation type in India. They are, however, associated with a variety of habitats and micro-habitats found in this country. For their healthy life and continuation, it is very important to protect these special environmental conditions that have preserved them through various geological ages. Each fern species has its own preferences for temperature, humidity, soil type, moisture, etc. although much work needs to be carried out to ascertain these special micro-climatic conditions (Shaikh & Dongare, 2009).The range of habitats sheltering pteridophytes include moist or dry rocks and boulders, tree trunks, fresh water bodies, including marshes and swamps, even mangrove swamps, forest floors and edges, alongside perennial streams, deep ravines and gorges, grasslands and cultivation areas of various crops, specially of tea, coffee and cardamom.