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Shola Forests
The hill forests are locally known as Sholas. The term
‘shola’ is a corrupt form of the Tamil word ‘cholai’ borrowed and incorporated
into forest typology. In Tamil the term ‘cholai’ (Malayalam: ‘chola’) refers to
a cold place, a thicket etc. Both ‘shola’ and ‘sholai vanam’ are literally
glorified in ancient Tamil literature, songs and films. All these connotations
refer to streams, rivulets and the associated forests. The shola forests
actually represent continuation of the evergreen forests in response to
elevational gradient, the sequence being: Wet Evergreen Forests - Subtropical
Hill Forests - Montane Wet Temperate Forests. The shola forests
as redefined by Meher-Homji (1986) include forests vegetations of the Peninsular
India, growing above 1500 m msl approximately. In terms of this broader
definition, shola forests are found all along the upper reaches of the Western
Ghats where the elevation goes beyond 1500 m msl. The first floristc account
of Shola Forests was that of Fyson(1915-21). It was the pioneering study of
Shetty and Vivekanandan(1968,1970,971,1972,1973,1991) that gave a good floristc
account of Sholas of Kerala. Blasco (1971) provided an account of flora and
ecology of Sholas of Western Ghats. The shola forests in the upper
plateau are dense and floristically rich with many endemic and rare species. The
trees in the sholas form a continuous canopy usually not exceeding 10-15m. There
is no marked differentiation into canopy layers. The tree bark is covered with
lichens, orchids, mosses and climbers. The crowns are generally rounded and
dense. Common tree species in the shola forests are Pithecellobium
subcoriaceum, Ixora notoniana, Syzygium arnottianum, Ilex denticulata, I.
wightiana, Michaelia nilagirica, Elaeocarpus recurvatus, Microtropis ramiflora,
Actinodaphne bourdellonii, and Symplocos pendula. The edges of the shola are
marked by trees such as Rhododendron arboreum var. nilagiricum, Ternstroemia
japonica, Ligustrum perrottettii, Turpinia cochinchinensis, Mahonia
leshenaultii, Rhodomyrtus tomentosa, Berberis tinctoria, Vaccinium neilgherrense
etc. and herbs and shrubs include Gaultheria fragrantissima, Moonia
heterophylla, Jasminum bignoneacium, Smithia blanda, Valeriana hookeriana and a
few species of Strobilanthes. The undergrowth in the shola is represented by
Strobilanthes sp., Impatiens phoenicea, I. coelotropis, Psychotria congesta,
Viola patrinii, V. serpens, Asplenium sp., and Arundinaria densifolia. Epiphytic
orchids in the sholas include Aerides ringens, Coelogyne nervosa, C. mossiae,
Eria dalzelli, E. pauciflora, and Schoenorchis filiformis. The common climbers
are Piper schmidtii, Rubia cordifolia, and Connarus wightii. Rapanea capillata,
Vaccinium leschenaultii, Impatiens tangachee, Sonerila grandiflora, Osmunda
regalis and Eurya japonica are usually found along streams. Broad-leaved
forests are found on the slopes descending from the plateau. The dominant tree
species found in the broad-leaved forests are Pittosporum tetraspermum,
Elaeocarpus munroii, Apollonias arnotti, Symplocos spicata, Gomphandra coriacea,
Garcinia gummi-gutta, Litsea coreacea, Prunus ceylanica and Photinia notoniana.
Major shrubs include Begonia subpeltata, Osbeckia lineolata, Polygala arillata,
Strobilanthes homotropus, Maesa perrottetiana etc. The Shola Forests are
important phytogeographically also. A very important species in this regard is
Rhododendron arboreum All other members of the of the genus Rhododendron in
India are confined to the Himalayan region. The flora also shows an affinity to
that of Sri Lanka which has tracts of Shola forests. The study of micro
flora of the Shola Forests has come up with promising results. 34 genera and 101
species have been identified from Munnar areas. The abundance of rare species
like penicillium is a portent for future biotechnological studies. There is a
treasure trove waiting to be tapped. This gives all the more reason for
conserving Shola Forests for the future generations.
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CONSERVATION ISSUES IN THE ABODE OF NEELAKURINJI AND
NILGIRI TAHR Sholas and grasslands of the high altitudes in the Western
Ghats are highly threatened E. Kunhikrishnan,
Lecturer, Department of Zoology, University College, Thiruvananthapuram, 695
034 It was an amazing sight that welcomed the early
European settlers in Ooty when the neelekurinji bloomed, making the meadows
mauve once in every 12 years. They called these hills ‘the blue mountains’ It
was the gregarious blooming of the plant Phlebophyllum kunthianum(Strobilanthes
kunthianus), which is endemic to the high altitudes of the southern Western
Ghats, that turned the hill tops apparently blue. The recent flowering of the
kurinji was in 1994. Because of the prominence during the gregarious blooming in
the high altitude grasslands, this plant got identification as the type species
of the high altitudes in the minds of the commons. Other than this, there are
many species of plants and animals, which are endemic to the high altitude
ecosystem. The high altitude ecosystem differs from all other ecosystems in
that high mountains constitute a unique habitat. It is an environmental complex
on the mountains, which are high enough to rise in to the semi- attenuated upper
parts of the atmosphere. Altitudinal changes of climate should sort and sift
species according to their climatic tolerance ranges, and so produce elevational
belts of vegetation in the same way that latitudinal differences in climate
produce latitudinal bands of vegetation. High up on the Western Ghats we
have three high altitude regimes namely the Nilgiris, Palnis and Anamalais .
Nilgiris rising from the north of Attappady plateau, north of Palakkad
gap(Palghat gap ), which culminate in to peaks like Mukurthi, Nilgiri, Anginda,
Sispara and Doddabetta. Anamalais and Palnis are immediately south to the
Palakkad gap. Anamalais rise from the plains of the gap sharply as a vertical
rock wall and expands from the Nelliampathis to the Anamudi peak, which stands
at 2695 m above msl forming the highest peak in the Indian peninsula. Palnis is
the Kodaikanal hills, comprising the eastern spur of the Western Ghats east to
Munnar hills. In all these regimes large part of the mountains remain 1800 m
above msl which afforded a subtropical ecoclimatic zone in the tropics. The
forests situated in the tropical latitudes cannot be strictly considered in par
with vegetation in the subtropical and temperate latitudes. The mountain tops
nave rugged rocky outcrops and pricipituous cliffs and a veil of mist. Down to
the cliffs there are vast expanse of grasslands interspersed with small and
large islands of dark green stunted forests, namely the ‘sholas’. These are
found mainly in sheltered valleys, depressions and ravines. ‘Shola’ might have
have come from ‘chola’ which signifies the dark shades of the thick stunted
forest or a small or large stream that emerges from the floor of the forest,
flowing down to the valleys. As the altitude increases, the trees become more
stunted and the branches of neighbouring trees are interlocked and have a thick
covering of epiphytes. Champion and Seth who classified the vegetation of the
Indian region taking into consideration many parameters, have included the
sholas under ‘Southern Montane Wet Temperate Forests’. In Kerala we
had vast expanse of sholas and high altitude grasslands in the Munnar region of
the Anamalai regime. A major share of this came under the Kannan Devan
concession land and had been cleared for raising the tea plantation a century
ago. After legislation in the early 1970s the excess land was taken from the
company and is now with the Kerala Forest Department. The prime grassland of the
Eravikulam, Poovar and Hamilton plateau were declared a national park in 1974
and it harbours the largest population of the highly endangered and only wild
goat in south India, the Nilgiri tahr, Hemitragus hylocrius. Factors
influencing animal and plant species distribution along elevation gradients are
complex, and not solely climatic or even ecological. In some cases evolutionary
aspects of the species may be important. Controversies are still going on
regarding the presence of the Himalayan taxa in the south Indian hill tracts.
Continuity with a more or less climatic unity between the Himalayas and the
Western Ghats during the ice ages has been suggested. Many scientists think that
the conditions that prevailed then facilitated continuity in the distribution of
plants and animals. After the retreat of the ice in the warm period, the
temperate condition remained only on the hilltops with substantial altitude to
maintain a low temperature, which supported the relict taxa. The high plateaus
above 1500m above msl imparted an extra tropical aura for the continued survival
of many species in the postglacial era. The Nilgiri and the Palni-Anamalai
tracts remain as islands with species common to these and also with endemic
species belonging to each of these regions. There were many species of caprinids
in the Himalayas. Some animals were supposed to have migrated to the south
during a glacial period eons back and evolved in isolation, to a different
species we now call as Nilgiri tahr. Interglacial warm periods pushed
these animals to the crests of the mountains up in the sky, the remnants of
which we see as the isolated populations along the cliffs and meadows of the
Nilgiris, Anamalais, Kodaikanal, Pampa, Highwavys and the Ashambu hills.
The closest relative of this animal, the Himalayan tahr, Hemitragus jemlahicus,
is seen in the upper reaches of the Himalayas. A third species, the
Arabian tahr, H. jayakari is in Sultanate of Oman. The Nilgiri marten, Martes
gwatkinsi, a member of the weasel family, is endemic to the forests of the high
altitude of the Southern Western Ghats. The immediate relative, the Himalayan
yellow throated marten, M.flavigula enjoys a wider distribution in the
Himalayas, the Assam hill ranges, Burma, China and the Malay countries. There
are at least 14 species of birds which are endemic to the shola grasslands of
the high altitude of the Western Ghats in Kerala. The close relatives of the
thrushes in these regions are seen in the eastern Himalayas. Salea
anamallayana is an agamid lizard endemic to Anamalais and Palni hill
ranges of the southern Western Ghats and Salea horsfieldii is confined to
the Nilgiris, Anamalais and Palnis. There are two more species of Salea existing
in the world, but seen in south China and Myanmar. There are some butterfly
species, which are endemic to the mountains 1500m above msl on the Western
Ghats. The Nilgiri grass yellow( Eurema nilgiriensis), Nilgiri clouded yellow
(Colias nilgiriensis), Red disk bushbrown (Mycalesis oculus), Red eye
bushbrown (Mycalesis adolphei ) , Palni bushbrown(Mycalesis mamerata davisoni),
Nilgiri fourring (Ypthima chenui )PALNI FOURRING (Ypthima ypthimoides) are the
examples. Eravikulam national park is the abode of another elusive cat
locally known as ‘pohayan’. Many members of the Muthuvan community, the local
tribe, swear that there is a plain-coated cat much larger than the jungle cat
and lesser than a leopard in the national park. So far there is no scientific
record on the existence of such an animal any where in the Indian peninsula. The
author has come across such an animal twice in the Eravikulam National Park. The
appearance matched with the descriptions given by the Muthuvans and that of Mr.
Mohan Alampath who managed the park for a pretty long term and had an
opportunity to observe the animal once for a longer duration. I strongly believe
that the animal can be a race of the golden cat (Catopuma), which is there
in the mountainous regions of the northeastern Himalayas and Southeast
Asia. Being a rare nocturnal cat it managed to skip form the eyes of the
scientists and the guns of shikaris. During a recent study by the Wildlife
Institute of India, in Eravikulam National Park, 308 plant species were
collected from the grasslands alone. More than 50 species were found to be
endemic to the grasslands and more than 30 species were listed as rare and
endangered. There were 64 species common with eastern ghats, 30 species with
similar high altitude areas(the patnas) in Srilanka,35 with Western Himalaya and
35 with Naga and Khasi Hills indicating phytogeographic affinities of the high
altitudes of the southern Western Ghats with these biogeographic zones.A
prominent tree with bunches of bright red flowers, Rhododendron arboreum, a
temperate species, is seen in the eastern Himalayas, and in the montane regimes
of south India and Srilanka. The tree in south is now considered as
subspecies R. arboreum nilagiricum . Michelia nilagirica is a shola tree
with fragrant flowers and is seen growing in similar habitats in Srilanka. The
endemic and endangered orchids like Brachycorythis wightii, Habenaria
perottetiana; the balsams appeared in the Red Data Book of Indian Plants
published by the Botanical Survey of India, like Impatiens johnii, I.
anamudica, I. macrocarpa, I. munnarensis, were reported from Eravikulam
National Park and the neighbouring areas and I. neo-barnesi, and I. nilgirica
were reported from Nilgiris
The
percentage of endemism is high and so the conservation value of the high
altitude grasslands is also very high. But due recognition has been denied to
this unique ecosystem. The degradation of the meadows and saholas of the
Nilgiris and Kodaikanal has started along with the arrival of the European
settlers during the early 19th century. Now the exotic trees like black wattle,
eucalyptus and pines have already replaced the natural vegetation of Ooty and
Kodaikanal. The major part of the grasslands of the Mukurthi tahr sanctuary in
the Nilgiris is under black wattle plantation. The second spell of doom of the
Munnar hills began with the planting of black wattle in the grasslands of this
area in the early 1980s.Most stretches of grasslands that were in blues during
the kurinji bloom of 1982 were choked with the profusely proliferating black
wattle when the gregarious flowering imparted the hills shades of blue again
in1994. The wattle was introduced as part of ‘afforestation of the wastelands’
programme in the forests of Kerala. The high quantity of tannin in the bark of
the black wattle virtually burnt all other plants in the vicinity. The shola
grasslands are to be protected at any cost. A scientist who studied this
ecosystem some decades back, correctly described it as a fossil ecosystem. The
relics of an ecoclimatic and geologic past is preserved in its pristine form at
least in certain parts of these mist laden canopies of the mountains. Eravikulam
is only about100sqkm in area. It was the only protected shola - grassland regime
south to the Palakkad Gap. Recently Mannavan shola and neighbouring high
altitude grasslands which are the remaining extensive shola – grassland
patches to north east of Eravikulam were also been notified as protected
areas. Redefining the boundary, taking in to consideration the
ecological boundaries of the tahr populations and the distribution of the
natural vegetation, can augment the area of the Eravikulam National park and
other protected areas in the neighbouring hills. Planting with wattle, pine or
eucalyptus and conversion and destruction of this unique ecosystem must be
stopped with immediate effect. Let the living fossil, the shola-grassland
ecosystem, which survived extremes of the vagaries of nature for eons remain
preserved for posterity.
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The Sholas and Grasslands in the southern Western
Ghats E. Kunhikrishnan, Lecturer.Department
of Zoology, University College, Thiruvananthapuram, 695 034
In the southern Western Ghats, the hilltops and plateaus 1400m. above the sea
level harbour a special kind of ecosystem. H. G. Champion and S. K. Seth in the
1930s and 1960s, while classifying the phytogeographic zones in the Indian
subcontinent, identified that the southern montane wet temperate forest and
grasslands exist in the high altitudes of southern Western Ghats. The
environmental complex that prevailed on these mountains nurtured an ecosystem
that could survive in the semi-attenuated upper parts of the atmosphere.
Altitudinal changes of climate could sort and sift species according to their
climatic tolerance ranges, and so produce elevation belts of vegetation in the
same way that latitudinal differences in climate produce latitudinal bands of
vegetation. The Nilgiris, Anamalais and Kodaikanal(Palnis) are the three
important high altitude regimes in the south. The blooming of neelakurinji
(Phlebophyllum kunthianum) periodically once in 12 years that imparted a purple
hue to the emerald grasslands on the slopes and plateaus were recorded by
the early westerner settlers in the Ootakamund. But the locals had already
called this hill range, Nilgiris- meaning, the blue mountains. The first written
records by the Britishers about the gregarious blooming phenomenon could be
traced in the volumes of the journal, Indian Forester published in the
late 19th century and in the Journal of Bombay Natural History Society of the
early 20th century.(The recent gregarious flowering was in 1994.) Much attention
had not been given to the special characteristics of the high altitude
vegetation in those days. P. F. Fyson was the botanist who seriously ventured to
study the plants in these inhospitable terrain and the leech infested forests,
during the British regime. Mehr Homji of the French Institute, Pondichery,
made some observations on the ecology of the hill stations in the south.
Studies have shown that a unique vegetation exists here which is
more comparable with the Alpine meadows in the Himalayas than the
Dipterocarpus and Hopea dominated forests somewhere in the lower altitudes in
the Western Ghats. Tropical montane forests are situated in the higher
mountain tracts of the southern Western Ghats, at an altitude above 1500 m,
interspersed with rolling grasslands. The montane forests are the stunted ever
green forests locally known as sholas. In the sholas the trees are stunted with
crooked branches thickly laden with moss and other epiphytes. The shola trees
have interlocking branches to withstand the high velocity winds blowing from the
west during the monsoon. During a recent study by the Wildlife Institute of
India, in Eravikulam national park, 308 plant species were collected from
the grassland alone. More than 50 species were found to be endemic to the
grasslands and more than 30 species were listed as rare and endangered. There
were 64 species common with the Eastern Ghats, 30 species with similar high
altitude areas in Srilanka, 35 with Western Himalaya and 35 with Naga and
Khasi Hills indicating phytogeographic affinities of the high altitudes of the
southern Western Ghats and of these biogeographic zones The
plant families Lauraceae and Rubiaceae are well represented in the sholas.
Acanthaceae members dominated among the shrubs. Many species of
Strobilanthes and Andrographis (both belonging to Acanthaceae) are endemic to
this region. In the Western Ghats, members of the flora families like
Ranunculaceae, Geraniaceae, and Saxifragaceae are seen only in such regimes.
Other members of these families are seen in the alpine meadows of the Himalayas
and temperate regions which are separated from the Western Ghats by thousands of
kilometers. The presence of the typical Himalayan tree Rhododentron arboreum on
the south Indian hilltops in the Nilgiris, Kodaikanal and Munnar is much
intriguing. It is not present on the Ashambu hills on the southern tip but is
there on the Srilankan hilltops. The Rhododendron in the south and in
the Srilankan 'patnas'(local name for the grasslands of Srilankan
hilltops) were earlier considered as separate species, viz. nilagiricum and
zeylanicus respectively. Now it has been established that the zeylanic, south
Indian and Himalayan Rhododendron do not have any taxonomic difference to
justify granting them separate species status. Rhododendron is considered a
native of south west Himalayas, where many species exist. Michelia
nilagirica is a tree in the sholas above an altitude of 2000 m above msl, which
is also present in the cloud forests of Srilanka at similar altitudes.
Pedicularis is a genus with many species in the meadows of the Himalayas,
but only two species, Pedicularis perrotettii and P. zeylanica are reported from
the south, from the hills 1300m above msl. The species Pedicularis zeylanica as
the name indicates, is found in the 'patnas' of Srilanka also. Geranium
nepalense seen in the high altitude grasslands is probably the only member of
the family in the south and in Srilanka. The same species and some more of
the genus are seen in the western Himalayas. The plants of the family
Asteraceae are in good numbers in the grasslands of the hilltops in all the
three regimes in the south. Genera like Anaphalis, Conyza, Gnaphalium, Gynura,
Cnicus, Artimesia, Senicio, Erigeron, and Picris in south, are exclusive to the
high altitude grasslands, where a subtropical climate prevails. Endangered
animals of the high altitudes The rocky escarpments and rolling meadows are
the home for the highly endangered and only wild goat of peninsular India,
the Nilgiri tahr(Hemitragus hylocrius).The total individuals of this
caprinid present today would be around two thousand only. Half of the population
is in the Eravikulam national park in Kerala and in the adjoining
Grasshills in the Indira Gandhi wildlife sanctuary, Tamilnadu. Another major
population of this mountain goat is in the Mukurthi sanctuary in the Nilgiris,
where less than 200 individuals survive. The Nilgiri marten, Martes
gwatkinsi, a member of the weasel family, is endemic to the forests of the high
altitudes of the southern Western Ghats. The immediate relative, the
Himalayan yellow throated marten, M. flavigula enjoys a wider distribution in
the Himalayas, the Assam hill ranges, Burma, China and the Malay countries.
There are at least 14 species of birds which are endemic to the shola grasslands
of the high altitudes of the Western Ghats in Kerala and Tamilnadu. The close
relatives of the thrushes in these regions are seen in the eastern Himalayas.
The lizard genus Salea is endemic to the Nilgiris and Anamalais. The
mountain wine snake, Ahetullah dispar is confined to the high altitude
grasslands of Anamalais and Ahetullah perroteti to that of Nilgiris. The
butterfly species the Nilgiri clouded yellow, the Palni four ring, the Nilgiri
four ring, red disc bush brown, the red eyed bush brown and the Indian
cabbage white are endemic to the mountains 1500 m above msl in the Western
Ghats. The Ecological holocaust on the mountaintops The last century saw
nothing less than a true ecological disaster in all the three major shola
grasslands regimes of the southern Western Ghats. The history of destruction
in the Nilgiris, Kodaikanal and Munnar was started by the initial colonial
settlers, more than a century ago. The first discovery of the 'salubrious
climate' that best suited the Europeans in the Nilgiris was by the
then Coimbatore collector Mr. Sullivan who first moved to Ootakamund in the
early 19th century. The plateau on the remote misty mountains was the homeland
of the pastoral tribe, the Thodas. In 1834, The Governor General of British
India spent several months in Nilgiris which was followed by a flood of
migration to procure land there. The natural vegetation in the sholas and the
grasslands depleted very fast. Introduced exotic temperate trees like Acacia,
(wattles) Eucalyptus and pines replaced the plants of the sholas and grasslands.
The high content of tannin in the bark of the black wattle virtually burnt off
the native endemic plants many of which now are in the list of plants
'presumed to be extinct'. In the Nilgiris, now there is no stretch of grassland
free of wattle, Eucaluptus and pine. The fate of Kodaikanal was not
different when it became a major 'Hill Station' in south India. The introduction
of tea plantations in the 1870s was the beginning of onslaught on the
sholas and grasslands in Munnar. The planting of black wattle and Eucalyptus in
the remaining grasslands in the pretext of social forestry and afforestation of
'wastelands' from the 1980s onwards was the last nail in the coffin. The
vestiges of the pristine grasslands that remain, comprise the Eravikulam
national park which escaped destruction by virtue of its special legal
status. Studies have shown that majority of the endemic plants of the
Munnar -Kodaikanal tract are highly threatened and many are already extinct
because of loss of habitat. In the coming decades conservationists will have to
fight very hard to save the remaining endangered native plants from extinction
because of the invasion of the black wattle in the grasslands and sholas.
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