FERN DIVERSITY IN THE SACRED FORESTS OF YANA, UTTARA KANNADA, CENTRAL WESTERN GHATS

摘要

Uttara Kannada district in Central Western Ghats has the unique distinction of having the highest forest cover in the country. Ecological research spanning over three decades reveal the presence of about 67 species of ferns and fem-allies. The highestnumber of pteridophytes species is found in Joida taluk (41 species) followed by Siddapur (30 species), Karwar (25 species) and Kumta (15 species). The semi-evergreen to evergreen forests of Castle rock, Kaiga and Yana and the primeval evergreen forestsof Gerusoppa Ghats are the rich pteridophytes diversity locations in the district. Yana located in the foothills of central Western Ghats known for unusual cathedral like towering rock formations is a place of pilgrimage. Forest ecosystems are humid andevergreen and rich in endemic species of flora, especially pteridophytes, which were hitherto unexplored. Field investigations during October-November 2012 in the region led to the documentation of 21 species of ferns. This emphasizes the need for detailed pteridological investigations in the valleys and gorges of central Western Ghats. Fern species of Yana region belong to 17 genera and 15 families and the noteworthy species are - Cyathea gigantea, very rare to be found in Uttara Kannada and are indicators of undisturbed forests. Bolbitis subcrenatoides and B. semicordata (endemic to south India) and others like Blechnum orientale, Adiantum phiJippense, Stenochlaena palustris, Pteris pellucida and Dicranopteris linearis were notable in the fern community. The ever increasing anthropogenic pressure in the district, particularly targeting wet and shaded valleys for cultivation, is a big threat to the fragile ecosystems with the sensitive pteridophytes.