|
Sacred Forests in the Central Western Ghats as a Unique Ecosystems for Lichen Conservation
By: Sumesh N. Dudani1*, Siljo Joseph2** and Sanjeeva Nayaka2***
The Western Ghats biodiversity hotspot are bestowed with complex geography, wide variations in rainfall, altitudinal decrease in temperature and large scale anthropogenic factors which have resulted in many unique ecosystems having different vegetation types. These ecosystems spread over six different federal states of India are well known for their rich diversity of flora and fauna. The part of Western Ghats passing through the state of Karnataka and encompassing the districts of Uttara Kannada, Shivamogga, Chikmagalur, Hassan, Kodagu and parts of Dakshina Kannada constitute the central Western Ghats. Abound with many protected areas (including national parks, wildlife sanctuaries, biosphere reserves), perennial rivers, hills of varying altitude, vegetation ranging from climax evergreen to deciduous forests and shola grasslands, and plantations (coffee, cardamom, coconut, cashew, arecanut). The central Western Ghats of Karnataka are home to very rare and critically endangered species viz.,SemecarpuskathalekanensisDasappa& Swam. (an evergreen tree only found in Kathalekan climax forest), Syzygium travancoricum Gamble and Madhuca bourdillonii (Gamble) Raizada (thought to be extinct but rediscovered in Uttara Kannada district) and Lion Tailed Macaque (the only second home in GerusoppaGhat of Uttara Kannada district apart from Silent Valley National Park).
However, despite the uniqueness and richness of this region in terms of species diversity, the forest ecosystems of the central Western Ghats are constantly battling against the increasing anthropogenic factors such as unsustainable natural resources exploitation, expansion of roadways and railways, illegal logging and hunting, large scale land conversion for agricultural purposes, diversion and exploitation of freshwater streams, etc. Nonetheless, there are some forest fragments scattered across the region which have been conserved and protected since many decades by the local communities for worships. Most of these forests are believed to be associated with some form of God, Goddess or Deity due to which they are called as “Sacred Groves” or “Sacred Forests”. All the flora and fauna thriving in such sacred forests are believed to be under the protection of the reigning deity, and any destructive or disturbing activity in that forest is strongly considered as a taboo. The sacred groves are often islets of fragile forests mostly relating to the climax forest of the region in the otherwise disturbed landscapes in present day India. They have been documented from different parts of India with the major concentration being in the Himalayas and the Western Ghats along with some records from central and western India.These groves not only provide a marvel for nature lovers and enthusiasts, but also play a significant role in conservation of our forests, soil and water resources as well.
The presence of different tribal communities along with a vast variety of socio-cultural and religious practices has led to the development of a sustainable relationship of the human communities with the sacred forests throughout the central Western Ghats. These sacred forests can range from one hectare to several hundred hectares in size and are generally known as ‘kans’ or ‘devrakadus’ in this region. In the past couple of years, there has been a significant surge in sacred forest studies throughout the Western Ghats biodiversity hotspot. However, most of these studies have mainly focused on the flowering plants as compared to the cryptogams. Among the cryptogams, lichens comprise of the most diverse group of organisms demonstrating a successful symbiotic association between the photobiont (algae or cyanobacteria) and the mycobiont (fungi). They have been able to establish themselves in various habitats right from the tropics to the temperate region. With more than 19,000 species in the world, lichens dominate about 8% of the earth’s land surface. India, being a biodiversity rich country, is also home to more than 2700 lichen species which are widely distributed in eight different lichen-geographic regions – Western Himalaya, Eastern Himalaya, Western Ghats, Eastern Ghats & Deccan Plateau, Andaman & Nicobar Islands, Central India, Gangetic Plain and Western Dry Region. The Western Ghats Biodiversity Hotspot is home to about 1200 lichen species among which the crustose lichens find their dominance followed by foliose and fruticose growth forms.
During our lichenonological studies in the central Western Ghats of Karnataka state, especially in the Uttara Kannada and Shivamogga districts, we have come across many small and big sacred groves having varied sets of socio-religious beliefs and practices which continue to harbour a rich diversity of lichens. Some of the noteworthy sacred forests are Hosagundakan, Kulundekan, Kurnimakkikan and Yelakundlikan in Shivamogga district, andKathalekan, Karikan, Heravalikan and Mattigarkan in Uttara Kannada district. Among these, Kathalekanis an erstwhile sacred forest, which is still in its pristine condition having climax evergreen forests along with a unique Myristica swampy ecosystem. On the other hand, Kulundekan and Kurnimakkikan were also once rich evergreen sacred forests which are now in severely degraded condition, owing mainly to large scale conversion of these forests for coffee and areca nut plantations along with other anthropogenic factors. The remaining kans still possess a temple with local deity where worshippers come from nearby areas to pay their respects and hence, the locals refrain from harming the biodiversity in these forests.
Together all these sacred forests harbour more than 120 species of lichens with the majority belonging to crustose growth forms followed by foliose and only a few fruticose species. The highest lichen diversity has been recorded from Hosagundakan in Shivamogga district, which is a unique forest worth mentioning. Hosagundakan is located little away from the state highway connecting Shivamogga to Sagara town comprises of an under construction temple with a small pond surrounded by majestic semi-evergreen forest intermixed with moist deciduous trees. According to available information and local folklore, Hosagunda was once an acclaimed centre of spiritual settlements with many temples built by the then rulers of this land which gradually fell into ruins after the rulers got extinct and people left this area eventually. However, the strong beliefs in the Gods of this land protected this forest as a sacred grove and today there is a rejuvenated interest and belief leading to rebuilding of desiccated temples on this land. Today this sacred forest is home to more than 60 different lichen species with a special mention of Pyxine endochrysinaNyl. This foliose lichen species belonging to Caliciaceae family is known only from Manipur state in India and has not been thereafter collected since 1892. The current collection from Hosagundakan comes as the only report of this species after a gap of 126 years.
The sacred forests provide an important and unique microhabitat and ecological niche not only for abundant lichen growth but also for novel lichen species. The evidence of this can be obtained from the many new lichen records that have emerged in our studies as well as many other studies too. One such example is that of the crustose lichen species Zwackhiarobusta(Vain.) Ertz (≡OpegrapharobustaVain.), which was reported as a new record for India. The species was found growing in the shady and moist habitats of Kathalekan sacred forest on the bark of IUCN Red Listed swamp tree Gymnacrantheracanarica(Bedd. ex King) Warb. Apart from this, two lichen species, Bacidia subannexa(Nyl.) Zahlbr. and Enterographapallidella(Nyl.) Redinger were also recorded from Kathalekan sacred forest as new records for the Western Ghats biodiversity hotspot and Karnataka state respectively.
With the constant developmental activities going on across the country, the central Western Ghats are facing challenges every day to sustain their forests and associated biodiversity. This region has been exploited many years for large scale commercial crops cultivation such as coffee, cardamom, areca nut, etc. which have emerged as major livelihood resources for the local and tribal communities. In a district like Uttara Kannada, despite these plantations, the forests are relatively less disturbed making it a suitable habitat for different flora and fauna. In contrast to this, the sacred forests in Shivamogga district are comparatively in degraded stage mainly due to large scale opening up of forest patches for various plantations. A classic example of this was observed in Kulunde and Kurnimakkikan which were once an important sacred forest providing habitat for evergreen and endemic tree species such as DipterocarpusindicusBedd. and VateriaindicaL. However, parts of these sacred forests were opened up for plantations which slowly spread in a large area resulting in severe fragmentation of forests and reduction in native biodiversity. Despite this, about 40 different species of lichens were recorded from these sacred groves. The lichens in these sacred forests had a good representation of foliose growth forms, mainly members of the families, Parmeliaceae and Physciaceae as compared to the other sacred groves. These lichenswere found colonizing on twigs, branches and trunks of trees in areas having canopy openings receiving good amount of light and wind.
Such studies further fortify the need to enhance our knowledge on the biodiversity composition of sacred forests as many of them still lie understudied. Today many sacred forests which were once the indicator of evergreen ecosystems of the Western Ghats have now merged with a mosaic of secondary forests. The lichenological explorations carried out in the central Western Ghats have revealed the presence of several endemic and novel lichen species harbouring in the sacred forests. More studies in this direction will enable us to have a better understanding of the lichen biota of these unique ecosystems as well as determine their current conditions using lichens as bioindicators. The sacred grove related culture is a celebration of biodiversity, and such forests need to be identified and conserved urgently for the sake of ecology and for upholding the spirit of conservation. Efforts through such studies are also being made to bring out the potentially sacred forests having rich and unique biodiversity for declaring them as ‘Heritage sites’ using the provisions of Biodiversity Act 2002. Apart from that, through our studies, we have always tried to rope in different stakeholders such as forest department officials, students at various levels in different colleges and schools, local communities, etc. towards awareness creation and conservation of lichens in this region. Any such steps towards protection of the remnants of the primaeval evergreen forests of especially South Indian Western Ghats are likely also to ensure better conservation of lichens exclusive to such forests, many of which are yet to be inventoried.
1Natural Heritage Division, INTACH, 71, Lodhi Estate, New Delhi - 110 003, India
2Lichenology Laboratory, Plant Systematics and Herbarium Division, CSIR-National Botanical Research Institute, Rana Pratap Marg, Lucknow - 226 001, India
E-mail: *[email protected], ** [email protected], *** [email protected], [email protected]
|
