Chapter-I
INTRODUCTION
1. INTRODUCTION
The flora of this country is more varied than that of any other country of an equal area in Eastern Hemisphere, if not in the globe (Hooker 1907). Darjeeling Himalaya is an integral part of the Eastern Himalaya, located in the northern side of Eastern India.The tertiary and quaternary have affected the Himalayan region and brought about many climatic changes and geographical variations. Many ancient elements have survived while some have differentiated to different races (Hara 1966). Darjeeling Himalaya is well known for its diverse range of vegetation and so is one of the richest in India (Yonzon 1976; Bhujel 1984; Das 1986, 1995).
The hilly regions of the State of West Bengal in the Federal Republic of India form an important part of Eastern Himalaya, which is recognised as a Biodiversity Hot-spot in recent times. Darjeeling is the northernmost district of the State. Excepting some parts of Siliguri Sub-Division, the entire district of Darjeeling is situated on the spurs of Singalila range of Eastern Himalaya and represents a great range of altitudinal varitions, from 200m or less at Siliguri to 3660m at Phalut. The hills of Darjeeling serve as one of the richest and interesting botanical regions in the whole of Indian sub-continent, and thus, have been a central point of natural and floristic attraction for tourists and nature-lovers. It is especially famous for three 'T's, i.e. Tea, Timber and Tourism. More specifically, it is well known as ideal place for health, and nature bestowed pristine beauty on the unique background of the world's third highest snow peak Mt. Kanchanjungha (8580m). For the nature lovers and botanists, hills of the Darjeeling district are of paramount significance by virtue of the rich flora and fauna (including a number of endemics). The beautiful landscape in its domain attracted the eminent researchers like Buchanan-Hamilton (1820), Roxburgh (1820-1824, 1832), Wallich (1820-1832), Griffith (1848), Clarke (1876, 1885), Hooker (1872-97), Hara(1966, 1971), Hara e?a/(1978, 1979, 1982), Ohasi (1975), Das et al (1985), Das and Chanda (1986, 1987, 1990), Das and Lama (1992), Samanta and Das (1995), Das (1995, 1998), Das and Panda (1997) Polunin and Stainton (1987), Pradhan and Rai (1983-1985), Sharma and Ghosh (1970), Grierson and Long (1983, 1984, 1987), Noltie (1994, 2000) are among others who have made a lot of contributions to the fiora of this hill station. However, a comprehensive flora is far ahead to come out in this line.
After the rise of the Himalayas, dense vegetation developed there almost in an undisturbed condition for hundreds of millions of years. Specially, the climate of Eastern Himalayas favors such development in a great way, which lead to the development of this richest floristic zone in the country. In the long drawn out process of migration of alien flora, their mixing, mutation, selection against different sets of climatic conditions, thousands of unique plant species evolved there, many of which, in turn, again migrated back to other floristic zones. Even today, the Eastern Himalayas sustaining over 30 % endemic higher plant species, is much-focussed region of plant diversity in the world. After the Rio de Genero Convention (1992), lUCN has identified very few Biodiversity Hot Spot Zones in the world. Western Ghat and Eastern Himalayas are such Hot Spots in the Indian sub-continent. Darjeeling district of West Bengal having an area of !3254, sq km and the State of Sikkim with its total area of 7299 sq km are the integral parts of this Biodiversity Hot Spot (Eastern Himalaya). The hills of Darjeeling are comparatively rich in biodiversity composition and thus, are the storehouse of rich biomass.
Darjeeling, more popularly known as Queen of the Hills as crowned by British during their 200 years rule in India, has presently four reserved areas i.e., two National Parks and two Wildlife sancturies. Neora Valley National Park is one of these, which is absolutely distinct and unique by its geographical features, virginity and species richness.
1.1 LOCATION OF THE PARK
Darjeeling distirct in the State of West Bengal has four sub-divisions, viz, Kalimpong, Darjeeling, Kurseong and Siliguri with its district administrative Headquarter at Darjeeling.
Neora Valley National Park is located in the Kalimpong sub-division of the Darjeeling district, and lies in the eastern side of the town of Kalimpong (Fig. 1.1). The geographical orientation of the Neora Valley falls between 26° 52' 3" - 27° 7' 3" North latitude and between 88° 45' - 88° 50' East longitude. The valley encompasses a total surface area of 88 sq km with many hill spurs, ridges and peaks ranging from 300m to 3100m.
Neora Valley National Park is situated on the flanks of Eastern Himalayas and has got common international boundary at one point, at an elevation of 2900m at Tinsimana. On the frontal North-Eastern side, it joins with the kingdom of Bhutan. The valley further stretches downward to join with the Doars area of West Bengal in the terai region in the foothills, and it also shares common boundary with the State of Sikkim in the Northern direction (Fig. 1.1). There is a common point where the parts of State of Sikkim, Darjeeling district of West Bengal and the Kingdom of Bhutan meet at a historical place called Tinsimana (meaning tri-junction, 2900m) where the stone pillars are raised demarcating the international boundaries (Fig. 1.1 «& Fig. 1.2).
1.2. LEGISLATION
Neora Valley National Park with its total surface area of about 88 sq km was declared as National Park by the Government of West Bengal in the year 1986 vide Govt. Notification No. 1818 Forest, dated 17.4.1986. This was done in realization of the Govt, to protect the rich biotic zones by establishing the natural reserve. This legislation added one more such reserve area to the already existing two Wildlife Sanctuaries and one National Park within the district of Darjeeling. The Government of West Bengal took the decision to declare the entire area of the Neora Valley as National Park in view of its biodiversity richness, remoteness, virginity, diverse topography and varied climatic, edaphic, altitudinal and biotic conditions along with their complex inter-relationship and species composition.
1.3. IMPORTANCE OF THE PARK
The Neora Valley National Park is one of the most important biosphere reserves in India. The Valley has its unique distinction because its dense primeval forest cover and difficult LOCATION MAP OF THE STUDY AREA
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Fig. No. I.I NEORA VALLEY NATIONAL PARK
Boundary of NVNP Beat/Range Office ^^^ Human Habitation Road ^^'^^ River Inter-NationcI Boundary State Boundary
Fig. Nol.2 terrain have kept explorers away from traversing it. It is a compact patch of 8,800 hectares with an altitudinal range varying from 300 m (amsl) to 3100 m (amsl). The rich floristic and faunistic diversity is one of the salient features of this reserve area. The Park is of great ecological interest when about 60 % of its total area is being estimated to be primeval forest area making this valley one of the best preserved biomes in India (Guha, 1982-83). The park has been a crucial piece of landmass providing ideal habitats for a wide range of microbes, flora and fauna, and has formed a core part of Eastern Himalayan Biodiversity Hot Spot. Besides, Neora Valley also acts as the repository of economic plant wealth, mainly medicinal and other various ethnobotanically valued plant species. The Valley also represents diversity of habitats, and sets an excellent account of majestic Himalayan wild flowers. The economic value of non-timber forest products of the Neora Valley such as medicinal plants, dyes and resin producing plants and bamboos are in fact very high.
The pristine natural forest, dense bamboo breaks. Rhododendrons with brightly colored flowers in full bloom, green valley, meandering rivers and streams altogether form the breathtaking vast picturesque landscape of Neora Valley National Park against the background of beautiful snow-capped Mount Kanchanjungha. Postmonsoon greenery enhances the beauty of the misty Neora Valley for very humankind to feast their eyes open. The beautiful pictures of the deep blue sky during autumn, partially covered with patches of cottony clouds seem to be enticing everyone. From the top of the valley, one can have a glimpse of swift-flowing Teesta River crawling like a snake towards the plain. The beautiful waterfalls trickling down the valley with a musical sound of endless tune add excitement to the park visitor. The flowers in myriad of colors in the Valley with magnificent backdrop of Mount Kanchanjungha's picture bedazzle nature-lovers visiting the Neora Valley National Park. During winter, the snow-covered cap of the valley enhances a serene picture of the Neora Valley.
The Park also acts as a source of water and provides a wide range of shelter for the flora and fauna. It has an unpredictable unique landscape for both flora and fauna serving to conserve the valuable natural resources like plants, animals and water bodies. The steep himalayan slopes, abundant rainfalls, fog-hazed weather and high humidity are some features of its significance. The views of sunrise from Rechila Peak (3100m) would always leave visitors bewitched. The lush landscape of pristine forest of Rhododendrons, Oaks, Hemlock, Silver-fir, Pine, valleys of colorfiil flowers and rich faunal species, mainly avi-fauna have made Neora Valley National Park a veritable paradise for nature lovers beyond doubt. The intact vegetation cover and its rich forest composition ensure a secure habitat for a plethora of Himalayan Flora and Fauna. Huge colourful flowers adorned the top of trees in the vicinity creating a sharp contrast in the pre-dawn haze. The scent from the aromatic species and from the flowers of other plants fills the spring air in the Neora Valley adding uniqueness and charm. Beside^the colorful flowers of Gentiana, Primula, Anemone, Ranunculus, Fragaria, Viola, Tripterospermum, Digitalis, Potentilla, Paris, Prunella etc. have added chastity to the rich ground flora, and everyone will be easily gripped by enchanting sight of these flowers.
Apart from this, the Neora Valley National Park also represents a diversity of faunal species. The Park is unique and very important from this point of view that more than 79 species of birds belonging to 21 families have been reported alone from the upper reaches of Neora Valley which forms only the VA part of the total area of the Park. According to Zoological Survey of India (ZSI), there are some 60 families of birds in West Bengal (Majumdar et al, 1992) which means that a small hill patch of Neora Valley National Park (i.e., 25 % of the total Park area) represents 41% of the total bird families of the vast State of West Bengal. Their gurgling, chirping and singing echo all over the dense forest of Neora Valley like a wild symphony. In the light of this fact, Neora Valley National Park is very important for avi-faunal study and thus prolonged and comprehensive study on the richness of avi-fauna of this region will be of great interest for further ornithological studies and to develop Neora Valley National Park as a special site of ecotourism (Mukhopadhyay et al, 1999). It is also more likely that a fair number of bird species await recording from the impenetrable thickets and deeply forested ridges of entire regions of Neora Valley. The most interesting point in the importance of avi-fauna species of Neora Valley is that the recorded species of birds also include most rare species like Buzzard {Butea sp.), Himalayan Redbreasted Falconet {Microhierax caerulescens). Spotted Seops Owl {Otus spilocephalns). Collared Pigmy Owlet {Glaucidium brodiei), Himalayan Owl {Strix alueo), Himalayan Goldenbreasted Tit- Babbler (Aleippe chrysotis). Golden Stadt's Redstart (Phoonicurcus erythrogaster), Indian Collared Burhchat (Sexicola torquata). Eastern Brown Crested Tit {Parus dichrosus). Eastern Plaincolored Mountain Finch (Leucostricta nemoricold) etc.
Besides,32 species of mammals belonging to 16 families have been reported from the upper reaches of the Neora Valley alone, out of which 9 are reported to be in schedule I of Indian Wildlife (Protection) Act, 1972. This figure when compared to the total mammalian species of India (410) (Nameer, in press) and the State of West Bengal represents 7.8 % and 17 %, respectively (Biswas et al, 1999). Very recently, the Department of Forest, Government of West Bengal and some Non-Govt. Organisations have communicated the presence of tiger population {Panthera tigris) in Neora Valley National Park. According to the report of Forest Department, Neora Valley National Park has the highest density of tiger in West Bengal at present. The valley is also the ideal home to one of the most cute but highly endangered animals of the world i.e.. Red Panda {Ailurus fulgens).
Neora Valley has an amazing diversity of flora that supports a large population of herbivore species, and is extra-ordinarily rich in avi-fauna as mentioned. Nature has bestowed Neora forest with a large number of butterflies. Rich plethora of insects is represented by a mammoth diversity of spiders, bugs, dragonflies, leaf hoppers, lace- wings, beetles, ants, bees and wasps. The rich flora and a much variable vegetation types of the Park thus, supply adequate foods and suitable habitats for all these animals. While the vegetation of the Park is supporting its great faunal population, it is also supporting the numerous vulnerable or endangered species of plants that can survive only in their natural habitats. So, one can expect that Neora Valley National Park, an immense storehouse of the rich biodiversity, would be one day the most prominent and important model Biodiversity Valley of the country.
Therefore, in true sense, Neora Valley National Park is a real conservatory which is not only housing a wide range of biological materials but is also working as an important link between other conservatories thereby providing an access to routes for the migration of the different species.
1.4. CLIMATE
Because of varied topographical and altitudinal conditions, the climate is much variable in different parts of Neora Valley National Park which varies from subtropical to cold- temperate conditions. During summer and monsoon, the climate of the valley remains warm and humid whereas moderate coldness persists with the advent of winter (November-mid-December) at lower elevations. The coldness becomes very severe towards the highest parts of the valley during vvinter, and some of its high peaks like Rechila, Jorepokhari etc. receive snowfall and often remain snow-covered for a short period (2-3 months). Many areas of the park remain foggy for major periods of the year and the sun is hardly visible during monsoon days. The rainfall is more frequent and maximum during monsoon. The maximum average temperature of Neora Valley has been recorded up to 28.8° C during August whereas the minimum average temperature being 6.4° C during February as recorded from the Regional Sericulture Research Station, Kalimpong at 975m altitude. As regards the rainfall and other meteorological data, there is no such Meteorological Station within or in the immediate vicinity of the Neora Valley. Thus, the meteorological information computed here is collected from Regional Sericulture Research Station, 7"" Mile, Kalimpong, which is at a considerable distance of about 40km by road from the location of the park.
A subtropical climate prevails in the lowermost parts (foothills) of the park whereas temperate and cold-temperate climate prevails in the places of higher elevations.
The average annual rainfall of the valley as recorded from the nearest Meteorological Station of the park at Kalimpong is 2246.8 mm. Rainfall is heavy during June-August, maximum rainfall taking place usually in the month of July (Table 1.1 & 1.2).
Table 1.1: Meteorological mean data (1990-1994) pertaining to rainfall, rainy days and temperature (maximum and minimum) as calculated from the obtained data Months Monthly No. of Rainy Mean Temperature Rainfall (mm) Days Min.(°C) Max. ( ° c) JANUARY 51.6 2.4 6.6 18.8 FEBRUARY 23 3 6.4 19.8 MARCH 36.4 4.6 11.2 24 APRIL. 87.4 8.2 14.4 27.2 MAY 150.6 12 16.4 27.6 JUNE 451.8 15.4 19.2 29 JULY 645.2 24.8 21.4 28.6 AUGUST 400.6 22.2 20 28.8 SEPTEMBER 340.4 18.4 18 27.8 OCTOBER 35.4 3.6 14.6 25.4 NOVEMBER 10 1.4 12.2 23.6 DECEMBER 14.4 0.4 8.8 19.4 Total 2246.8 116.4 169.2 300 Average 187.23 9.7 14.1 25
Source: Regional Sericulture Research Station, 7"" Mile, Kalimpong. Altd. 975m.
The data of mean temperature, rainfall and no. of rainy days presented in the above table are based on tables nos. 1.2 & 1.4. m^lJ:MaimRimDm Si(Mx:s.Ee^ondSeriaJtureEeseardiStatioi% 'f'Mlhe,Ka&rpof^AM:975m. 700 600 500 E 400 ^ 200 100 0 -BLl I JAN. FEB. MAR. APR. MAY JUN JUL. AUG. SEP. OCT. NOV. DEC. Months Fig. 1.3: Monthly mean rainfall (1990-94) at Kalimpong 1.4.1. PRECIPITATION Varied amount of precipitation is prevailing altogether at different places of the Neora Valley. The mean highest monthly rainfall recorded at Regional Sericulture Research Station, 7"' Mile, Kalimpong is 645.2 mm during July, while the mean lowest rainfall recorded is 10mm during November. The frequency of rainfall during monsoon is maximum, where there is no barrier for penetration of monsoon clouds, e.g. Jorepokhari, at 3030m elevation (Chopra 1985). The average number of rainy days around Kalimpong areas near the National Park as found in the met-data is 116 days per annum (table 1.2). Considering the monthly average rainfall, Kalimpong area is most rainy area with average monthly rainfall of 187.23 mm compared to Gorubathan area with only 23.16mm at Sermali Agriculture Farm (table 1.3) located at the foothills of Neora Valley, and receives the lowest precipitation level in the area. Table 1.3: Monthly Rainfall (1998-2000) at Gorubathan as recorded at Sermali Year 1998 1999 2000 Average No. of Rainfall No. of Rainfall No. of Rainfall No. of Rainfall Month Rainy (mm) Rainy (mm) Rainy (mm) Rainy (mm) Days Days Days Days Jan. Nil Nil Nil Nil Nil Nil Nil Nil Feb. Nil Nil Nil Nil 1 18.00 0.33 6 Mar. 4 38.25 Nil Nil Nil Nil 1.33 12.75 Apr. 8 33.92 9 12.72 7.00 45.82 8 34.13 May 9 39.82 22 32.61 19.00 35.87 16 36.1 June 27 58.23 21 41.20 24.00 112.80 24 57.01 July 30 70.8 28 51.96 30.00 48.99 29.3 56.69 Aug. 29 68.34 26 5L68 28.00 47.60 27.66 55.87 Sep. 15 38.62 28 36.68 25.00 28.05 22.66 34.45 Oct. 12 42.13 12 35.30 7.00 66.50 10.33 47.97 Nov. 1 25.3 3 12.30 3.00 12.30 2.33 16.63 Dec. NIL NIL NIL NIL NIL NIL NIL NIL Total 135 415.41 149 274.45 144 415.93 147 368.59 Average 11.25 34.62 12.42 22.87 12.00 34.66 11.89 30.71 Source:Sermali Agriculture Farm, Gorubathan. Altd. 270m. 1.4.2. TEMPERATURE The average maximum temperature for the Neora Valley as recorded from its nearest meteorological station at Kalimpong over a period of five years (1990-94) has been found to be 28.8 °C during the month of August, and the average minimum temperature being recorded 6.4 °C during February. However, this data is taken in the generalized view, and does not necessarily imply to the exact temperature figures of the Neora Valley National Park as the temperature often hovers around -5° C during winter (our observation on Dec 12, 1994) at Rechila Peak of the valley. Data thus presented in the table is interpreted from the data procured from the Regional Sericulture Research Station at Kalimpong, which can be taken into consideration in the prevailing context, particularly this being not so fer from the Neora Valley. The table 1.2 depicts the collective figures of month-wise mean maximum and minimum temperature (1990-94) and the table 1.4 shows the individual year mean maximum and minimum temperature as recorded from the Regional Sericulture Research Station, Kalimpong for the past consecutive five years since January 1990 to 1994. In the higher elevated areas of the Neora Valley, the occurrence of frost is a common feature, and the seasonal snowfall is also in the natural routine of the climate. In winter nights, the mercury goes down to the freezing point and often to an extent of (-) 5" C (our observation on Dec 12, 1994 at Rechila Peak). 30 25i 1 r _: 1 20 1 _ r - 10 - p _ 5 n - JW. Fffl WR. AFR IVAY JLN JUL fUS. SB>. OCT. NOV. DHl IVIonths Fig. 1.4: Monthly mean (max. & min.) temperature (" C) during 1990-94 at Kalimpong 1.4.3. HUMIDITY AND SUNSHINE The Neora Valley environment maintains a high humidity level round the year. The higher places of the valley towards north usually remain humid ahnost round the year. During rainy season, the trend of decrease in humidity being found towards lower and southern valley slopes. The drier months are March and April when the relative humidity continuously go down. Sunshine is frequently disturbed due to formation of dense fog and clouds, usually in the morning and afternoon. The fog and mist formation goes to its extreme duriog the month of July in the places like Choudha Feri, Pankhasari, Alubari, Chitray, Dhamdhamey Dara, Hattidara, Jorepokhari, Tinsimina etc. of the Neora Valley, while it is also frequent 10 •o •^ n\ 00 IN •i-1 r- rf r^ CN 0 NO 0 0 0 CO CN CN CS CN ON 0(3 1 « in O (U 1—1 •^ -* 00 o\ 0 CO r- 00 in 0 -^ ON 00 00 S -q 0 yi 0 ,—1 CN CN T—1 00 1* 0 CO (->1— 1 -^ r-t VI o\ rs 0 0 M- ON 0 in 0 r^ m ex ,_ B CO in 0 t^ NO CO ON ^ r~ m en •^ t^ CN •-3 u ^ 00 1^ IN m r-~ NO t— 00 NO •* 0 CO 00 I—1 \n V3 ON (N NO C3N 0 00 00 m CO 0 IN 0 cN NO CO 1 1« o o „ 0 t^ •o 00 CN NO in NO CO la- CS ON 00 m § 1 00 0 IN VO 00 ON t—< 0 00 in r_l CO ' I rH r-H f—1 1—< 1—t CN CS I(~>N 1— 1 1—c ON NO »—< r-1 fn g — 0 ,—1 vfi t^ 00 ON 0 00 0 NO in CS CN 0 (N M ol (S (N CN CO CNl CO IN CS CS 0 CO NO CN vo t^ u-1 10 CO NO in t^ CN CO ON NO in ,—4 P 'rf ^n •^ lAl in NO in NO r-t C3N cN § ^ CS (S V2 •o VO CO 0 NO NO m CO CO IN 0 NO CO I I—1 (S CN CN CS CS CS CN V3 'O CO TT 0 CO 00 •^ IN 00 IN CO 1—1 (I—^< ,_( 1—1 ^,. CN IN IS r- CO i O M *—' 1^ -1 •" 1 s •* m r~- ON CO 0 CS CO CO CO ^ 00 ON CO § .3 00 0 V5 00 CT\ f7N 00 00 00 CO 00 CO ^ 00 m o :s^ r—I o\ t—t \o 00 CJN 0 r- I^ 00 IN in CS CO a I t—1 ol •B S 01 0 S3 J 0 > 0 3 > 0 lU > en :z; 1 2 1 2 •1 :§ 0 Q < during the months of June, August, and occasionally also in September. Sun is almost invisible during some of the monsoon days and remains enclosed within the heavy fog and mist, and the continuous over-casting of the sky with clouds is a common feature. While the sky remains moderately clouded in other seasons, the winter mornings are frequently filled with lifted fog. However, the clear sky and sunny days prevail during autumn whereas sky remains smoggy during the summer or spring. 1.5. TOPOGRAPHY Neora Valley is situated on the flanks of Eastern Himalaya and its topography is extremely variable with varied altitudinal range from as low as 300m near Samsing in terai region to as high as 3100m at Rechila Peak, the highest point of the valley. The V- shaped "Neora Valley is almost like a conglomeration of several undulating hilly ridges and furrows dissected by low-lying hill slopes, small streams and rivulets. Stretching right from terai region to almost the lower alpine zones, the valley also forms a trans- boundary line with Sikkim and Bhutan (a neighbouring country) at some points. Low and deep undulating spurs and hilltop in the V-shaped valley are covered with dense vegetation except being nude or open at some parts. The natural scene is very attractive by virtue of the picturesque landscape of the valley, lakes, streams and dense green vegetation. Alubari Khasmahal, the only flat piece of land in the valley ascend upward to a historical place called Tinsimana meaning "tri-junction"- a common boundary where the parts of the Royal Kingdom of Bhutan, State of Sikkim (a sovereign country before it merged with India in 1975) and Darjeeling district of West Bengal meet at that point. The higher ridges of the valley descend dov^nward to the tea garden settlement near Samsing at the terai region. From the Rechila peak of the valley, one can have a glance of the beautiful scenaries of the part of Chumbi Valley of Tibet, part of the Royal kingdom of Bhutan, parts of Sikkim State and the hilly and terai regions of the Darjeeling and Jalpaiguri districts of West Bengal. The river Neora originates from below this peak-point taking on other small tributaries from the hill spurs and crest on its way downward, flowing towards the river Teesta in the plain. Some of these tributaries and subsidiary streams are named, and all have their origin within the domain of the park. From the peak of the Neora Valley (3100m), the hill slopes and furrows descend downward to Jorepokhari (3040m), Tinsimana (2900m) and further down to Chitray (2600m), Lower Alubari (2280m), PHE source (2130m), Jaributti (2195m), Sakam (1800m), etc. The hill ridges lying in the west of these places extend further towards Rechila Park (2280m), Pankhasari (2200m) and Choudha Feri (2260m), ultimately leading to Labha (2000m). The hill ridges of the valley towards eastern side descend down to places called Tangta (1300m), Todey (1250m), Godak (1200m) and Jholung (1100 m). On the other side, the hills of Neora Valley rise high from Gorubathan (300m- 1000m) and Samsing forests (300-1200m) to Machuki (1300 m), Ruka Hill (2500m), Thosum Beat (2500-2800m) and finally to Rechila Peak (3100m). 1.6. DRAINAGE SYSTEM In the entire Neora Valley, the largest water source is the Neora Khola (literally meaning narrow stream/river) that originates from Jorepokhari (Bhujel, 1992-93). The seepage water of other smaller lakes also forms the source and catchment of the Neora Khola. The Neora khola is also fed by many other smaller tributaries and jhoras originating from 12 different hill ridges and crests and lie enclosed in the valley. Rising from Jorpokhari, this hill stream is fed by nine main streams and sixteen subsidiary streams, the main feeder being the Thosum Chu (Guha, 1982-83). 1.6.1. LAKES There are quite a few beautiful lakes at the hill summit, in the midst of forest cover,and as well as deep in the valley between hilltops, some of them often drying up during the dry season. Amongst these prominent water bodies/lakes of the Neora forest, there are three beautiful high altitude lakes supporting a large number of plants and animals, specially the migratory birds. At the hill summit of trijunction (2900m), a couple of small lakes serve the purpose of water source to a number of animals including transboundary animal population that come from across the adjoining forest of Royal Kingdom of Bhutan and vice-versa. These animals use the transboundary forest areas as their ideal habitat making use of drinking water source of the Tinsimana Pokhari. Jorepokhari, which literally means paired lakes, are the permanent lakes of the Neora Valley, situated in an open patch of flat land at the upper region of the Rechila Chowk and is situated at an altitude of 3040m. The size of the lake is about 200 x 200m and is located above the international trijunction demarcation. The lake also serves as the permanent source of drinking water to the cattle, herdsmen, hunters, orchid and medicinal plants collectors, timber thieves, trekkers, businessmen travelling to the transboundary places of Bhutan, Sikkim, Kalimpong, Dooars area, etc. through the forest route of Neora Valley. Besides this, Jorepokhari also provides the seepage water to the small tributaries of the river of Neora serving as the ultimate source of the Neora Khola. (Plate VIII: 81). Apart from these lakes, another but comparatively larger lake (300 x 200m) and unnamed because of its remote location, is situated in the bowl-like ground remaining almost unexposed being covered by dense canopy of gigantic trees, and lake marginal vegetation. (Plate VIII: 77). 1.6.2. STREAMS AND RIVERS There are many small water tributaries originating from different hilltops and ridges, flowing down to join small springs or khola. Neora Khola (Mo/ar=narrow river) is one such prominent but small rain-fed river with the maximum catchment area of all the river systems in the Neora forest. Flowing through the valley, Neora khola is about 60 km long with the average width of its bed varying between 90 to 120m (Bhujel, 1992-93). In fact, the Neora Khola is one of the main sources of drinking water for the people of Kalimpong town situated about 50 km away from the Neora Valley. A small stream called Asala khola emerges from the cliffs and crest of the hills of Machuki and flows down to Phari, Samsing and Suntalay down in the foothills. Chel khola, another stream originates from the forest valleys of Sakam and passes down via Ambiok and Gorubathan, and finally joins the River Teesta in the plains. There are also other small perennial streams/jhoras, many of which however in true sense, acquire the shape of streams only during the rainy season. Some of these perennial streams or jhoras of the Park include Siri Khola, Thosum Chu, Ruka Kholsa, Norchu, Sakam khola, etc. Apart from this, there are few unnamed seasonal jhoras or tributaries 13 originating from undulating deep and low crest and ridges of the Neora Valley, but remain almost dried up during winter. 1.7. VEGETATION STRUCTURE The region of the valley can be broadly divided into two vegetational zones- (i) Mixed semi-deciduous forests and (ii) Rhodendron-forest (Plate VIH: 79). While the latter type is forming a thick and dense cap over the hills (above 2800m), it is poor in floristic richness with more or less barren to thin forest floor species composition. In contrast, mixed semi-deciduous forests occupying the regions below 2800m altitude are very rich in floristic composition of all habit groups including trees, shrubs, climbers, annuals, geophytes, epiphytes, etc. While the vegetation is mostly dominated by angiosperms, there are appreciable number of ferns and four species of gymnosperms including two planted conifer species of the plantation forests (Taxus baccata, Tsuga dumosa and the planted two species being Pinus longifolia and Cryptomeria japonicd). The flora is extremely important with the occurrence of numerous interesting and useful species of plants. Based on the present study and some earlier fragmentary studies (Majumdar et al 1984; Bhujel 1992-93), the forests of Neora Valley can broadly be grouped into following types depending upon the elevation of the area and the dominant species composition: Tropical Forest (Low Hill Forest, upto 1000m) Sub-tropical Forest (Middle Hill Forest, 1000-1600m) Temperate Forest (Upper Hill Forest, 1600-2400m) Cold Temperate Forest (2400-2800m) Rhododendron/Sub-Alpine Forest (2800-3000m) Alpine Scrubs (3000m and above) Also, there are some secondary grasslands and plantation forests (upto 2300m). 1.7.1. TROPICAL FORESTS Extending upto an elevation of about 1000 m, the valley has tropical type of forested vegetation which can further be categorized into sub-types as evergreen, semi-evergreen, moist and dry deciduous forests. The forest area of this tropical zone comprises of the dense broad-leaved semi-evergreen to evergreen forest forming a closed evergreen canopy. The tree species in it are attaining a height of 20 to 30 metre and exihibit clear demarcation with bushy and dense herbaceous undergrowth. The canopy is composed of mostly zizantic species of trees. Amongst the trees, prominent ones include Schima wallichii, Bombax ceiba, Terminalia myriocarpa, Albizia spp., Toona ciliata, Lagerstroemia parviflora, Bauhinia purpurea etc. Other species of trees encountered in the lower belt of the park include Tetrameles nudiflora, Duabanga grandiflora, Syzygium formosa, Litsea polyantha, Sierculia villosa, Mangifera sylvatica, Garcinia paniculata, Ostodes paniculata, Pterospermum lancifolium etc. Tree ferns and Pandanus nepalensis are commonly seen interpersed in tlie forest in comparatively open areas. Some shrub species of this range include Morinda angustifolia, Coffea bengalensis, Desmos chinensis, Desmos dumosus, Miliusa roxburghiana, Buddleja macrostachya, Murraya paniculata, Murraya koeningii, Paramignya monophylla, Leea guineensis, Cassia tora, Desmodium sequax, Desmodium laxiflorum, Crotalariaferruginea, etc. This type of vegetation is observed in the areas of Samsing, Phari, Machuki, lower part of Sakam, Gorubathan, Chel, upper part of Jaldhaka, etc. 14 1.7.2. SUB-TROPICAL FORESTS Forests of middle hill zone (1000-1600m) comprise of evergreen as dominant species. This zone encompasses the areas such as upper parts of Saicam, Machuki, Chel, upper belt of Todey-Tangta, Phaparkheti, lower parts of Ruka Hills, etc. Alongwith the deciduous trees, the large epiphytes and climbers also occur in this zone. Most common trees in this part of forest area are Quercus glauca, Castanopsis indica, Castanopsis tribuloides, Castanopsis hystrix and Michelia champaca. Other dominant species of trees of this region include Exbucklandia populnea, Litseapolyantha, Alnus nepalenis, Phoebe attenuata, Juglans regia, Engelhardtia spicata, Macaranga postulata, Betula alnoides, etc. Thin patches of bamboo (Dendrocalamus hookeri) also occur in the lower belt of the zone. Epiphytic orchids, aroids and other epiphytes and climbers etc. are abundantly represented. The undergrowth of the forest consists of numerous herbaceous and shrubby species. Dichroa febrifuga, Sida acuta, Dobinea vulgaris, Desmodium multiflorum. Smithia ciliata, Crotalaria ferruginea, Eupatorium odoratum, Litsea cubeba, Thysanolena maxima, etc. are some of the shrubs frequently seen in this forest zone. Some climber species growing in this range include Clematis buchaniana, Clematis gouriana, Kadsura heteroclita, Desmos dumosus, Cyclea bicristata, Stephania glandulifera, Stephania elegans, Dicentra paucinervia, Natsiatum herpeticum, Berchemia floribunda, Rhamnus nepalensis, Gouania leptostachya, Parthenocissus semicordata, etc. Cardamine flexuosa, Nasturtium officinale, Viola diffusa, Viola pilosa, Viola hamiltoniana, Viola sikkimensis, Sagina japonica, Drymaria diandra, Drymaria villosa, Portulaca oleracea, Oxalis corniculata, Impatiens pulchra, Impatiens spirifer, Impatiens drepanophora, etc. are the common herb species growing here. 1.7.3. TEMPERATE FORESTS This type of forests is found in the altitudinal belt of 1600-2400m of the Park. The vegetation in this part of the valley is extremely thick and covered by mostly medium sized and evergreen species of trees. Deciduous trees also occur here but these form a small proportion in the vegetation. The Park areas such as Jaributti, Pankhasari, Alubari, Hattidara, Dhamdhamay Dara, Chouda Feri, Zero Point, Chonko Bhir, PHE Source, Middle Rechila, Chitray, Ruka Beat, Lower parts of Thosum Beat, Mulkharka, Reshete, etc. fall in this temperate forest zone. The vegetation is mainly mixed-type, however, oaks and laurels cover a large portion of forests. The occurrence of mosses, lichens and other epiphytes were mainly concentrated on the branches of gregarious oak trees. The prolific growth of the species of smaller herbs, shrubs and fern on the forest floor is a common sight inside the forest. Woody climbers are also prevalent. Common taxa predominant in this range include Quercus lamellosa, Quercus pachylla, Quercus lineata, Michelia cathcartii, Michelia doltsopa. Magnolia campbelli, Castanopsis hystrix, Castanopsis tribuloides, Machilus edulis, Acer campbelli, Betula alnoides, Symplocos glomerata, Symplocos theaefolia, Prunus nepalensis, Prunus cerasoides, Eurya japonica, Phoebe attenuata, Evodiafraxinifolium, Taxus baccata, Pieris formosa, etc. Alnus nepalensis with its quality of rapidly establishing itself on the landslide-affected areas is found growing extensively along watercourses on the lower part of these forests. The preponderance of this taxon has precisely delineated the altitudinal zones by virtue of their pattern of occurrence. The dense thickets of shrubs in this forest range include Lycesteria formosa, Lycesteria stipulata, Viburnum erubescence, Viburnum cordifolium, Maesa chisia, Ancuba himalaica, Elsholtzia fruticosa, Ilex crenata, Rubus lineatus, Rubus splendidissimus, Daphne bholua, Maesa chisia, Ardisiaspp., Neillia thyrsiflora, Lonicera sp, Arundinaria sp, Gaultheria griffithiana, Agapetes saligna, etc. These species constitute impenetrable shrub layer (thickets) in the forest and form a dense shrub canopy. Apart from this, there are patches of forest where bamboo species, mainly the Dendrocalamus hamiltonii grow gregariously interspersed amidst the forest areas. The herb species composition of this forest zone includes mainly Fragaria nubicola, Viola biflora, Impatiens bracteata, Impatiens spirifer, Hemidesmus indicus. Begonia gemmipara. Begonia sikkimensis, Cynoglossum glochidiatum. Campanula pallida, Potentilla polyphylla, Potentilla sundaica, Epilobium clarkeanum, Epilobium royleanum, Oxalis corymbosa, Oxalis acetosella, Didymocarpus aromaticus, Chirita macrophylla, Ajuga lobata, Prunella vulgaris, etc. 1.7.4. COLD TEMPERATE FORESTS (2400-2800m) The richness of arboreal flora gradually decreases within and above this range but the diversity of herb species including endemics of Eastern Himalayas is found to be increasing in generalised term (Hara 1966; Bhujel 1996). Apparently, this vegetation zone can be distinguished into mixed temperate forests usually at the upper elevations and the Hemlock-Acer-Rehododendron mixed forests. The vegetations of both the forest types are enriched by the addition of numerous climbers, shrubs and herbaceous ground cover. Some of these shrub species which may be mentioned here include Arundinaria moling, Gaultheria fragrantissima, Smilax glaucophylla, Himalayacalamus falconeri, Dendrocalamus hamiltonii, Dichroafebrifuga, Helwingia himalaica, Aconogonum molle, Schisandra grandiflora. Daphne bholua, Hoelboellia latifolia, Agapetes saligna, Vaccinium retusum, Pieris formosa, Lyonia ovalifolia, Neillia rubiflora, Rubus paniculatus, Rubus lineatus, etc. Two species of the coniferous trees {Taxus baccata, Tsuga dumosd) are also found intermingled with the tree canopy of the cold temperate forests but their abundancce is quite low. Apart from this, they are sparsely present in the hill tracts. Interestingly, Alnus nepalensis is seen nicely growing over the slope and landslide areas. Amongst numerous herb species of this vegetation zone, important ones to mention are Poa annua, Potentilla fulgens, Fragaria nubicola, Peracarpa carnosa, Viola pilosa, Elsholtzia strobilifera. Prunella vulgaris, Hydrocotyle himalaica, Gnaphalium qffine, Fimbristylis dichotoma, Streptolirion volubile, Carex inanis, Isacne albens, etc. One important natural phenomenon observed in the cold temperate forest zone is that the invasion of bamboo. Upto the upper reaches of this belt (2800m), the bamboos have rapidly infested the forest vegetation. Bamboo is seen to gradually replacing the other species of plants thereby establishing themselves in some areas. Only few shade-loving plants are growing there in these bamboo-infested forest patches including one endangered species of Balanophora polyandra. 1.7.5. RHODODENDRON/SUB-ALPINE FORESTS (2800-3000m) The forest zone in the sub-alpine range of the Neora Valley is mainly composed of Rhododendrons and conifers. In the lower belt of sub-alpine zone, tree species like Quercus lineata, Quercus pachyphylla, Betula utilis, Acer campbelli, Acer sikkimensis 16 and Magnolia campbellii have extended quite often, and are gradually replaced by Rhododendron-forest at the higher-up elevations. Interspersed among the Rhododendrons are Tsuga dumosa, indeed not much enough. The Armdinaria spp. exhibits its full growth and dense patches forming thick undergrowth in Rhododendron and silver-fir mixed forest. Various species of Rhododendron in the zone include Rhododendron arboreum, Rhododendron barbatum, Rhododendron falconeri, Rhododendron dalhousie. Rhododendron edgeworthii, Rhododendron grande, Rhododendron glaiicophyllum. Rhododendron grffithianum, Rhododendron triflorum, etc. The areas of the valley within this range include mainly upper regions of Chitray, Thosum Hills, Tinsimana, Jorpokhari, left and right hill cliffs of Jorpokhari, etc. (Plate Vni: 79). 1.7.6. ALPINE SCRUBS (3000m and above) At about 3000 m and above this elevation, vegetation at some places has adapted in the form of scrubs towards the higher steeper slopes, and in true sense, there is no tall tree in this range. The vegetation at this zone represents the mosaic of Rhododendron Settsu, Rhododendron anthopogon, Rhododendron thomsonii, Rhododendron campanulatum and, species of Aconitum, Viola, Primula, Arisaema, Geranium, Fragaria, Ranunculus, Meconopsis, Potentilla, etc. are found frequently growing. 1.7.7. GRASSLANDS A few grasslands of secondary origin are also seen in the valley in Alubari Khasmahal, Jorpokhari and Jaributti areas of the National Park. Biotic and climatic factors like grazing animals and snowfall check the natural regeneration at these areas. Commonly growing grasses of these grasslands include Eulalia mollis, Poa alpina, Helitotrichon virescens, Agrostis myriantha, Festuca leptopogon, etc. Apart from these species of grasses, some herbaceous species growing in the area include Potentilla polyphylla, Fragaria daltoniana. Primula denticulata, Halenia elliptica, Ranunculus diffusus, Anaphalis triplinervis, Plantago erosa etc. 1.7.8. PLANTATION FORESTS In some parts of the National Park such as Chouda Feri, Zero Point (2100-2300m) etc., the natural vegetation has been replaced by plantation forest by the Forest Department. The growing need of timber to human and the revenue generation activity of government have resulted into the indiscriminate felling of timber trees and Department of Forest has initiated the plantation of monocuture or mixed coniferous species. The plantation of rapidly growing monoculture plant speceise, namely Cryptomeria japonica and Pinus longifolia have certainly a direct impact on the rich biodiversity of the Neora Valley. In Alubari Khasmahal area, Forest Department is raising seedlings of plants like Exbucklandia populnea, Acer campbellii etc., and these are also being planted in semiopen places of the Park. However, the plantation forests near Chouda Feri are highly invaded by the bamboos. 1.8. PREVIOUS FLORISTIC WORK The nature bestowed rich biodiversity of this Himalayan belt have attracted a number of researchers, scientists and naturalists from around the country and the worldover. The botanical splendor of Eastern Himalaya can be realised from the visits of D. Don (1825), 17 followed by the visit of famous naturalist Griffith in 1847 and Sir Joseph Dalton Hooker during 1848-49. J. D. Hooker undertook an increditable expedition work visiting many places of this region and made a vast collection of plant meterials, many of which now being the representative specimens today, which are also included in the comprehensive monomental work titled The Flora of British India in seven volumes (1872-97). His much-appreciated work include The Flora of British India (1854, 1872-97, 1904), The Himalayan Journals (1854), Flora Indica (1855) with T. Thomsons, Rhododendrons of Sikkim Himalaya (1849-51), and A sketch of the Flora of British India (1907). Eventhen, we donot find any mention of floristic richness of Neora Valley nor the reference of plant samples collected from this pocket of Biodiversity Hotspot. The Valley was hitherto unknown to almost all the successive botanical explorers after Hooker including Thomas Anderson (1832-1870), J.A. Gammie (1894), Robert Pantling with Sir George King (1898), George H. Cave (1897) with Sir W.W. Smith (1909), H.J. Elwes (1877), C.B. Clarke (1876, 1885), George Watt (1881), C.C. Lacaita (1913) and many other botanists. Although these infamous botanists visited this Eastern Himalayan belt, Neora Valley was overlooked in their floristic explorations, and in true sense, not even the checklist of plant species or study report pertaining to the bioresources of the Neora Valley in the broad sense is available as of today. However, some botanists have made contributions to the flora of Darjeeling-Sikkim Himalayas including J.S. Gamble (1878, 1895), A.M. Cowan and J.M. Cowan (1929), S.K. Mukherjee (1940), H. Hara (1963, 1968, 1971), H. Kanai (1966, 1971), M. Mizushima (1968), H. Ohashi (1975), A.J.C. Grierson and D.G. Long (1979-1987). Apart from this, in the post 1940s, botanists such as K.P. Biswas (1967), B.N. Ghosh (1951), R.S. Rao (1963), B.D. Sharma (1970) also visited Sikkim Hills and the adjoinging areas but failed to reach the virgin valley of Neora. Similarly, many other botanists like B. Krishna (1987), R.C. Srivastava (1992, 1996), A.P. Das (1987), D.G. Long (1990), P.K. Hajra and D.M. Verma (1996) and H.J. Noltie (1994 and 2000) have also visited the adjacent hilly terrains leaving behind the Neora Valley. Moreover, N.C. Majumdar, B. Krishna and M.C. Biswas's joint paper (1984) which deals with the brief description of the vegetation of Neora Valley and adjacent regions in Kalimpong Forest Division is the first report of botanical excursion to this place. Their paper gives very brief floristic account especially of the lower areas, and it appears that they too have missed to reach the interior difficult terrains of the valley. R.B. Bhujel in his expedition to Neora Valley, visited a few interior areas of the valley in 1993 in connection with the study of environmental damage caused by the controversial Neora drinking water project, and has mentioned some plant species in the report. Very recently, A.K. Samanta and A.P. Das (1998) have studied the angiospermis climbers of the valley, and have described some interesting climbers. Nevertheless, no comprehensive work either on flora or fauna of the virgin Neora Valley has appeared until now. 1.9. IMPORTANCE OF THE PRESENT WORK The hilly region of West Bengal forms an important part of Eastern Himalayas, which is recognised as a Biodiversity Hot Spot by lUCN in recent times. District of Darjeeling is one such hill station of the State of West Bengal having rich and interesting botanical regions in the whole of Indian sub-continent and has been a central point of attraction for large number of domestic and foreign tourists, researchers and the plant hunters. 18 The region is being estimated to represent corhparatively a higher percentage of flora of the country, representing all the major groups of plant kingdom including a number of endemics (Chetterjee 1940; Biswas 1967; Das and Chanda 1987). Migration of several species from adjoining countries and their naturalization is a unique feature in this hill region (Das 1995; Bhujel 1996). Neora Valley forest is one such species-rich area and is declared National Park by the Government of West Bengal. The Neora Valley National Park is surrounded by the rich forests of Sikkim and Bhutan, and has got a vast tract of virgin vegetation. There has been insignificant or no study at all, about the vegetation and flora of this valley. The hilly terrains, deep valleys and interior regions of this part of Darjeeling District were hitherto remained unexplored. The present attempt is a floristic work through extensive trekking or field visit, survey and documentation of the floristic elements of the Neora valley. In this study, latest nomenclature of plant species, taxonomic description, their local names, flowering and fruiting periods, the places of their distribution, ecological status, and the ethnobotanical knowledge of local people about its floristic elements have been dealt with which will be extremely useful for many scientific purposes. Besides, a checklist of the flora of Neora Valley achieved in this work will be an important information base for the researchers, students, scientists, and planners and overall to the government for its proper utilisation and management. This will equally be useful for the people of Botanical Survey of India involved with the assignment of preparation of Flora of India. The Neora Valley keeps a great meaning in terms of ethnobotany of the hill people. People living in the periphery of the valley maintain their own science and economy, and meet-up their regular needs of food, medicine, fuel, numerous useful household materials, etc. The ethnobotanical information recorded from the valley will be much useful for further ethnobotanical studies. The Flora may be very useful for the assessment of our natural wealth and resources. This may also help to identify, segregate and conserve the economically important plant species viz., medicinals, wild edibles, timber, ornamental, aromatic, spices and many other non timber forest produces (NTFPs). Most importantly, this flora may find a prompt and justifiable use in the overall planning and strategy of many developmental programmes. Researchers including botanists, naturalists, foresters, ecologists and economic planners may use the flora for policy advocacy, conservation activities, sustainable exploitation, mass education, planning environmental strategies, and propagation of the endangered and highly vulnerable floristic elements. Herbarium so developed in this study is a source of authentic information and may find an utmost use by researchers, students, teachers, foresters and scientist in the future. 19 0 ON NO NO 0 CO 00 cs o) n r- t—1 NO w-i NO NO NO NO co t—» r~- in i .^! cs O) CN CN