GEO-ENVIRONMENTAL BACKGROUND

Transcription

1 CHAPTER II GEO-ENVIRONMENTAL BACKGROUND 2.1 Introduction In an Anthropogeography, it is very much pertinent to study in detail to understand the physical background such as location, climate, natural resources, topography, etc. to understand human adjustment to its natural setup. The determining factors of nature on culture and economy of man is more prominent among less developed societies. The Brokpas of Arunachal Pradesh is a glaring example; by and large depend on their forest for their survival. The study of physical background where nomadic herding is practiced will help us in better understanding the adjustment of Brokpas to their forests. 2.2 Location Arunachal Pradesh is located in the extreme North-Eastern corner of the Union of India in the Trans-Himalayan region. It is situated between 26 º 28' to 29 º 33' North latitudes and between 91 º 31' to 97 º 30' East longitudes. It shares a long international frontier, 160 km with Bhutan to the west, 1080 km with Tibet (China) to the north and north-east and 440 km with Myanmar to the east; while it borders the states of Nagaland and Assam to the south-east and south. Arunachal Pradesh has an area of 83,743 sq. km. This accounts 2.55% geographical area of the country and 32.81% of the North-East India, excluding Sikkim. It has 0.11% of the country s total population, with an average density of 17 persons per sq. km. (2011 Census).

2 West Kameng district with its headquarters at Bomdila is located approximately between 26 º 56' and 28 º 01' North latitudes and 91 º 30' to 92 º 40' East longitudes (Figure 2.1). The district is bounded by Tibet (China) and the Tawang District (Arunachal Pradesh) on the north, East Kameng District (Arunachal Pradesh) on the east, Darrang District of Assam on the south and Bhutan on the west. 1 The district covers an area of 7,422 sq. km. This is 8.86% geographical area of the state. West Kameng district is divided into 13 administrative circles (Table 2.1 & Figure 2.2). As per 2011 Census, West Kameng district has 260 villages with a total population of 83,947 persons comprising 46,155 males and 37,792 females. The average population density is 11 persons per sq. km. The literacy rate of the district is 69.40%; male 75.66% and female 60.80% respectively, as per 2011 census. The sex ratio is 819 females per 1000 males. Table 2.1 Administrative divisions of West Kameng District Sl. No. Sub-division Circle Year of creation 1. Bomdila i) Bomdila Bhalukpong i) Bhalukpong Kalaktang i) Kalaktang ii) Balemu Dirang i) Dirang 1954 ii) Thembang 5. Nafra i) Nafra Rupa i) Rupa ii) Shergaon Shingchung i) Singchung 2006 ii) Kamengbari 8. Thrizino i) Thrizino ii) Jamiri Source: District Statistics Office, Choudhury, S.D., Arunachal Pradesh, District Gazetteers, East Kameng,West Kameng and Tawang Districts,Shillong,1996, p2-24-

3 Figure 2.1 Base map of the study area Source: Digitized from topographical sheets No. 78M, 83A & B, Published by Survey of India. -25-

4 Figure 2.2 Administrative Divisions of Tawang and West Kameng District Source: Digitized from District Statistical Handbook of Tawang and West Kameng,

5 Tawang is one of the administrative districts of Arunachal Pradesh, which is situated in the western part of the state. It is located roughly between 27 º 25' and 27 º 55' North latitudes and 91 º 35' and 92 º 20' East longitudes. The district is bounded by Southern Autonomous Tibet (China) in the north, Bhutan (Trashigang) in the south south-west and west and West Kameng district in the east and south-east. The district is also known as The Hidden Paradise. The district covers an area of 2,172 sq. km. 2 which is 2.59% geographical area of the state. It has a population of 49,977, which shares 3.61% of total population of Arunachal Pradesh. The average density of population is 23 persons per sq. km. as compared to 17 persons for Arunachal Pradesh. The literacy rate of the district is 60.61% out of which 68.54% are males and 48.75% are females. The Sex ratio of the region is 701 females per 1000 males, which is lowest in the state (2011 Census). The McMahon line which came into being formally in 1914 following the Shimla Agreement signed between British government and independent Tibetan government. The area has been gifted/ presented to British India and came under effective Indian administration on 12 th February 1951, when Major Bob Khating 3, the then Assistant Political Officer re-established India s sovereignty over Tawang. In 6 th Oct, 1984, Tawang was carved out from West Kameng district to become the 12 th district of Arunachal Pradesh. Administratively, Tawang is divided into three sub-division i.e. Tawang sub-division, Lumla sub-division and Jang sub-division with Tawang town as its headquarters. The district has 10 administrative circles under three sub-divisions (Figure & table 2.2). 2 Choudhury, S.D., Op.cit.p.2 3 For detail refer to Chakravarty, L.N, Glimpses of the early history of Arunachal, Director of Research, Government of Arunachal Pradesh

6 Table 2.2 Administrative divisions of Tawang District SL. NO. SUBDIVISION CIRCLE YEAR OF CREATION 1. Tawang Sub-Division i) Tawang ii) Kitpi Jang Sub-Division 3. Lumla Sub-Division Source: District Statistics Office, 2012 i) Mukto ii) Thingbu iii) Jang iv) Bongkhar v) Lhou i) Lumla ii) Zimethang iii) Dudunghar Geology Geologically West Kameng and Tawang districts have been divided into two group viz. Se La group and Bomdila group (Figure 2.3). Se La group is structurally the highest unit which is separated from the Dirang formation to the south by Main Central Thrust (MCT), this suite of medium grade to high grade rock derived its name from the Sela pass in West Kameng district (Bakliwal and Das, 1971). The predominance of migmatites, lit-par-lit injection, and higher grade of metamorphism and profuse intrusions of tourmaline granite characteristically differentiate this sequence from the structurally underlying Dirang Formation. 4 In Se La pass area, the rocks exposed include garnetiferous gneiss, sillimanitekyanite-garnetbearing gneiss, migmatite, lit-par-lit biotite gneiss, calcgneiss / marble, Staurolite-bearing-schist, tourmaline granite, quartzite and veins of pegmatite. 5 4 Dutta, N.D. Director General, Geology and Mineral Resources of Arunachal Pradesh, Geological survey of India,No.30 Part IV I(i) Arunachal Pradesh,2010.pp Ibid. -28-

7 A sequence of low to medium grade metasediments with associated gneisses and younger granitoids occupying expansive areas throughout the lesser Himalaya of Arunachal Pradesh from Siang Valley in the east to Kameng Valley and Bhutan in the west designated as the Bomdila Group. From west to east the Bomdila Group is overlain by the Dirang Formation till east of Subansiri river. The southern contact of the Bomdila Group is also known to be thrusted bringing it over either the Gondawanas or Neogene- Quaternary sequences in western and Central Arunachal Pradesh. The rock of the Bomdila Group is subdivided into Tenga Formation, Dedza Formation and Dirang Formation and intrusive in ascending order. The low grade metasediments consisting of green phyllite, metavolcanics sericitequarz phyllite and quartzite originally described from Tenga valley by Das et. al., (1975) are referred to as Tenga Formation. 6 The Tenga Formation is also divided into an upper and a lower member on the basis of lithostratigraphic section measurement in West Kameng district. The upper member which is also known the Jameri Member is predominantly a quartzite with thin bands of phyllite and black shale. The quartzites are grey to milky white, thinly bedded, occasionally schistose and mylonitised. The lower member is also called Along Member is characterised dominantly by basic metavolcanics with thin bands of flaggy quartzite, marble/ dolomite and sericitic quartzose phyllite are seen in Nechiphu-Jameri and Foothill Tenga sections. A thick sequence of low grade metasedimentaries comprising garnetiferous mica schist, phyllite, sericite quartzite, 6 Dutta, N.D. Director General, Geology and Mineral Resources of Arunachal Pradesh, Geological survey of India,No.30 Part IV I(i) Arunachal Pradesh,2010.p

8 Figure 2.3 Geology of Tawang and West Kameng District Source: A Resource Atlas of Arunachal Pradesh, published by Deptt. of Planning, Govt. of Arunachal Pradesh,

9 calc-silicate and tremolite-actinolite marble unconformably overlying the Bomdila Group truncated in the north by the MCT has been designated as Dirang Formation. 7 A sequence of medium grade meta-sediments comprising quartzite, garnetiferous mica schist with occasionally developed staurolite, marble, calc-silicate and amphibolites exposed in the Tawang- Woming La section in Tawang district has been described as Lumla Formation (Tripathi et al., 1979 and Singh, 1988). 8 However the systematic mapping around Tawang and Lumla by Kaura and Basu (1982) clearly indicate that this sequence occurs in a tectonic window bounded by the rock of the Se La Group. A sequence of low grade carbonaceous mica schists and micaceous quartzite containing biotite porphyroblasts transverse to schistosity, mapped by Rana and Duttagupta (1996) in Thinbu, Panga, Sera and Thungung areas of Tawang district has been described as a part Tethyan sequence. On the basis of textural characteristic, this has been tentatively correlated with the Chekha Formation (Early Cambrian) of the adjacent Bhutan Himalaya. 9 Lithologically, the Thingbu Formation comprises a lower argillaceous unit represented by mica schist and an upper part represented by fine to medium detrital quartz mica schist and flaggy quartzite. 2.4 Physiography Mountains are the most imposing feature of topography of West Kameng and Tawang districts. A greater part of these districts is tangle of hills and mountains. Some strips of comparatively level ground along the foothills belt and with patches of plain land in the river valley. 7 Ibid. 8 Dutta,N.D. Op,cit p10 9 Dutta,N.D. Op.cit.p11-31-

10 In West Kameng, there are three principal mountain ranges, viz Sela Range, Bomdila Range and Foothills Range. The Sela range consists of a series of mountains arranged in the form of big line from Tibet in the North, Bhutan in the west and thus forming a tough terrain to pass through it. The altitude of Sela range varies from 4,270m to 4,570m and the legendry Sela Pass is at the height 4,181m. The Bomdila range, having an average height of 2,745m is separated by a 1,372m high valley of river Dirangchu/Meyongchu, a tributary of Kameng River. Bomdila, the district headquarters lies in this range, at an altitude varying from 2,470m to 2,745m. South of the Bomdila range lies the Foothills Range having hills with quite low altitudes and the area is mostly plain. The area of the Foothills Range is full of tropical forests with trees of great economic values and various type of wild game. 10 Tawang represents a high altitude mountainous tract; where the elevation of the district ranges between 1,829m to 6,707m. The topography of West Kameng and Tawang is the east-north-eastward extension of Bhutan Himalaya. To the north of the lower Himalaya terrain, it is rugged and numerous north-south ridges joins the east-northeast: west-south-west great Himalayan ranges known for towering peaks such as the Gorichen, the highest peak in the Tawang district is locally called Sa-nga-phu, is approximately 6,707m. 11 The Kangto (7,103 m) is situated in West Kameng district. These regions having altitude between 3,000m to 7,000 m is snow covered with barren mountains and is mostly no permanent settlement except yak herders stay with their livestock. Only 4.60 % of total area is below 500m. The Latitudinal zone between 1,000-1,500m represents 9.24%. 10 District Statistics Hand book of West Kameng District, District Statistics Office, Bomdila Tawang at a Glance published by the Office of Deputy Commissioner, Tawang. -32-

11 Figure 2.4 Altitudinal zones of the study area Source: Generated from Digital Elevation Model of Shuttle Radar Topographic Mission (USDA),

12 About 30 % of study area falls under the altitudinal zone of 1,500-2,500m. The altitude between 2,500-5,000m which covers 48 % of total area is favourable for rearing of yak and its allied species. Only 1.81% area is above 5,000m. Altitudinal zones and total area with percentage under different categories is represented in figure 2.4 and table 2.3. Table 2.3 Total area and percentage under different altitudinal zones Sl. No. Altitudinal zones (in metres) Total area (in sq. km.) Percentage 1. < > Total Source: Generated from Digital Elevation Model (SRTM) 2.5 Drainage The Kameng River flows through the West Kameng district and ultimately joins the mighty Brahmaputra River in plains of Assam. This river receives many tributaries, of which Bichom is the major river (Figure 2.5). The Bichom River, called Humschu by Akas, 12 rises from the Himalayan watershed in the extreme north-east corner of the West Kameng district. Flowing through the Miji and Aka hills it takes an eastward course. The Bichom is fed by its two major tributaries the Dirangchu/ Meyongchu and the Tenga river before it joins the Kameng river. Tenga and Dirangchu take rise from the Orka La range and runs along many important Monpa villages of Dirang and Bomdila circles. 12 Choudhury S.D., Arunachal Pradesh, District Gazetteers, East Kameng,West Kameng and Tawang Districts,Shillong,1996.,p5-34-

13 Figure 2.5 Major Drainage System of the study area Source: A Resource atlas of Arunachal Pradesh,

14 Near Dirang the river is fed by Sangtichu, a stream that descends from the north, and then flows eastward until it meets the Bichom river in the Aka hills 13. The river Tenga originates in the south-west region of the West Kameng district. It flows eastward and joined by many streams. In the source region it is known as Kharchi and in Sherdukpen area is called Dublo Kho and Dunuk Kho. After entering Tenga valley area it is known as Tenga river. The Tawang Chu (Tongsheng Grangma) and Nyamjangchu are the principal rivers that form the drainage system of the Tawang district (Figure 2.5). Tawang Chu originates from the Gorichen mountain ranges in the north beyond Se La and flows westward along the valleys of Tawang and Lumla into Bhutan. The name of the river Tawang Chu starts after the confluence of Mago Chu and Nyukcharong Chu near Kyelatongbo. Nyukcharong Chu originates in Tibet at an elevation of 2,240m, while Mago Chu originates in India at an elevation of 3,360m. Mago Chu traverses south-west and joins Nyukcharong Chu. The important tributaries and stream besides these two are Nuranang Chu, Dungma Chu, Garong Chu, Larong Chu, Yaminrong Chu, Dotangla Chu, Rudi Chu, Shelkang Chu/Shaikang Chu, Chubiu Rong stream Thumble Rong stream, Larongphu stream, etc. While Nyamjang Chu originates from Tibetan plateau and flows down along Panchen villages (Zemithang). The major tributaries of Nyamjang Chu are Namkha Chu and Taksang Chu. Other tributaries are Le Chu, Sundarong Chu, Samba Chu, Bludi Chu and Nyadi Chu. Both the rivers meet at Kungba Village near Indo- Bhutan border before entering Bhutan. The two main rivers, Tawang Chu and Nyamjang 13 Ibid. -36-

15 Chu show a combination of dendritic, trellis and parallel drainage pattern. 14 Almost all the transhumance activities take place along the rivulets and streams as water is one of the most important natural resource required for animals to drink. 2.6 Climate Arunachal Pradesh is so much influenced by climatic variations that we can see even in their social, cultural and economic life of the people. The weather and climate of the state is so distinct from the rest of the country. The most important variables are the north to south variation in elevation, variability of rainfall, trend and ranges of temperature. The climatic types in the state vary from humid meso-thermal of the southern foothills and plains to alpine in the higher altitudes of the northern parts of the state. The climate of the region is predominated by the Himalayan system, altitudinal variation, rapid changes in topographic and terrain conditions which control variations and differences that significantly influence the climatic pattern. It is located in the subtropical zone and falls within the heavy rainfall area. As a result the southern and southcentral sections of the state have humid. In the northern part, sub-alpine and alpine climate predominate. The climate of the West Kameng and Tawang districts is influenced considerably by the mountainous terrain and its elevations along the southern slopes of the Eastern Himalayas, cut across by long, deep and narrow valleys through which the main rivers and most of its tributaries flow. Spatial variations of climate in West Kameng district are considerably due to the nature of terrain. Temperature fluctuates according to elevation and exposures to the sun. In this district, altitude varies from 213 m at Bhalukpong to 14 Jamba,T. Indo-Bhutan Border Trade: A case study of Tawang(India)and Trashigang district of Bhutan unpublished M.A dissertation, Department of Geography, Rajiv Gandhi University, Itanagar 2012 p

16 7,090m (Kangto peak). At Bomdila (2,700m), the headquarters of West Kameng, experiences C of maximum temperature in the month of July and August and minimum(-) C in the month of January (Table 2.4 & Figure 2.6). Temperature begins to rise in March, remains till August. The month of July and August are generally the warmest. From the month of October onwards the temperature falls gradually till January. Annual rainfall exceeds 250cms over the southern parts. The rainfall decreases with elevation as one proceeds north and north-west. Southern part of the district gets more than 70 per cent of the rain during the period June to September, while northern half receives 50 to 60 per cent of the annual precipitation in the same period. Pre- monsoon showers during March to May account for slightly more than 20 per cent for the southern half and less than 20 per cent for the northern half. Winter precipitation is experienced during October to December over the northern parts constitutes 10 per cent of the total annual rainfall. From the month of November to March, the region is periodically affected by western disturbances passing across or near it from west to east. During this period of disturbances, precipitation, mostly as snowfall, occurs over the northern parts. In the West Kameng district humidity is generally high throughout the year; the winter months being less. Thunderstorms mostly occur during the pre-monsoon months; March to May, often violent and accompanied by hail. Hill fog is a normal feature of weather during the monsoon months. In the valleys, morning fog occurs frequently in the winter. The climate of Tawang is as varied as its altitudinal variations and terrains. Like most of the country, it is affected by monsoon. Temperature varies according to elevation and it goes down to below freezing point ( C) during winter and during summer maximum temperature is C in Tawang area (Table 2.5 & Figure 2.7). -38-

17 Table 2.4 Mean Annual Temperatures, Rainfall and Relative Humidity of Bomdila, Month J F M A M J J A S O N D Max (ºC) Min (ºC) RH (%) Rainfal l (mm) Source: Office of RWD, Bomdila, Government of Arunachal Pradesh. Figure 2.6 Mean Annual Temperatures, Rainfall and Relative Humidity of Bomdila,

18 Table 2.5 Mean Annual Temperatures, Rainfall and Relative Humidity of Tawang, Month J F M A M J J A S O N D Max (ºC) Min (ºC) RH (%) Rainfall (mm) Source: Arunachal Pradesh State Pollution Control Board, EIA-Hydrometeorology and Office of RWD, Bomdila, Government of Arunachal Pradesh, Figure 2.7 Mean Annual Temperatures, Rainfall and Relative Humidity of Tawang,

19 It is fairly cold throughout the year in Mago-Thingbu area located at the height about 3,400m from mean sea level and the temperature never rises above 15 0 C and remains much below freezing points during winter. While low lying valley like Namtsering (1,900m), which lies westward towards the border of Bhutan, the temperature varies from 4 0 C to 35 0 C and is hot and humid during summer and moderately cold during winter. Cold season starts from early part of November and continues up to late March. During this season, some places above 2,240 m experience snowfall. The district receives heavy snowfall during winter. Weather remains pleasant from September to early part of November with little chilly air. Rainfall is heavy in the months of June, July and August, with an average annual rainfall of 180 mm. The monsoon is season marked with hailstorms and thunderstorm that bring landslide and numerous misty, overcast days. 2.7 Soil Arunachal Pradesh is endowed with a wide range of climate, physiography, geology and vegetation resulting in formation of different kind of soils and they are grouped into following four categories. 1. Soils of Warm Per-humid Eastern Himalaya Ecosystem. 2. Soils of Warm Per-humid Siwalik Hill Ecosystem. 3. Soils of Warm Per-humid Purvanchal Ecosystem and 4. Soils of Hot-Humid Plain Ecosystem. 15 Tawang, Bomdila and (Dirang subdivision of West Kameng) fall under the category of Soils of Warm Per-humid Eastern Himalaya Ecosystem. In this ecozone 15 Goswami, C., Soils of Arunachal Pradesh-Their Problems and Potentialities, an article in Souvenir, Farmers Development Workshop and KishanMela, Pasighat,

20 climate is characterized by mild summer and moderate to severe winters. The mean annual soil temperature varies from 18 to 20 0 C. The soils of the ecozone are heterogeneous in nature. The soils of ridges are mostly shallow, loamy to sandy in texture, excessively drained and subjects to severe erosion. The soil developed on moderately steep side slopes are usually moderately shallow to deep, well to somewhat excessively drained, loamy to fine loamy in texture. Soils in narrow inter hill valley are deep, poorly to imperfectly drained, fine in texture with slight erosion and more flood hazard. Most of the soils show little profile and rich in humus. These soils are strongly to moderately acidic in nature (ph 4.5 to 7.2), rich in organic matter. The major soil related problems are erosion and landslide, limited soil depth, soil acidity and poor base saturation. On the contrary, the acid soils rich in organic matter with high rainfall cold climate favour the plantation of different temperate and subtropical fruits like apple, plum, peach, kiwi, etc. Soils of Warm Per-humid Siwalik Hill Ecosystem cover the area comprising the Tenga Valley of West Kameng district and some parts of Tawang district. The climate of the region is characterized by mild summer and moderate winter. The mean annual precipitation exceeds 200 mm. The soils developed in ridges are moderately deep, loamy to fine loamy and moderate to severely eroded. Soils on hill slopes are deep, loamy to coarse/fine loamy in texture with moderate to severe erosion hazards. Soils are strongly to moderate acidic in nature (ph 4.2 to 5.7), medium to high organic matter content (1.0 to 2.5% OC). The major soil related problems are shifting cultivation, leading to deforestation and severe soil erosion, gravelled soil surface, excessive leaching of -42-

21 essential nutrients to poor base saturation. On the contrary, foothill region favours plantation of tea, horticultural crops, and agro forestry. 2.8 Flora and Fauna Flora Arunachal Pradesh abounds in forests, meadows and swamps, each with its own ecological characteristics. The vegetation in the state may be broadly classified into three major types i.e. Tropical, Temperate and Alpine. Each type has a number of sub-types, subject to vertical and horizontal variations in elevation. Tropical evergreen and semi evergreens are confined to the foothills and plains. There are patches of sub-tropical moist deciduous forest above the tropical zone, particularly between 2,200-2,800 m. up to the elevation of 3,800 m is the zone of conifers and above that till the snow line are zones of sub-alpine and Alpine forest and meadows. The West Kameng and Tawang district are the home of wide variety of flora and fauna. These districts are said to be only region in the world to harbour all three species of goral. The lower region of these districts receives heavy rainfall of more than 400cm per annum both from South-West and North-East monsoons. The average relative humidity varies from 75 to 95 percent. The average maximum and minimum temperatures vary considerably with altitude. The flora of these districts can be broadly classified into three main types, (a) Tropical forest type (b) Temperate forest type (c) Alpine forest type (Figure 2.8) and total area under different type of forest (Table 2.6). (a) Tropical forest type: These forests can be divided into two sub types: (i) Tropical Semi-evergreen forest (ii) Sub-Tropical forest or mixed forest. -43-

22 (i) Tropical semi-evergreen forest: This type of forest found along the foothills with an altitudinal range up to 900 m. In the study area this type of forest accounts percent. The forests are characterized by dense vegetation, chiefly comprising of tall evergreen tree species like Dipterocarpus, Artocarpus, Tetrameles, Bombax, Mesua, Duabanga dillenia mixed with bamboos, Pandanaus, climbing canes and tree-fern like Cythea gigantia. (ii) Sub-Tropical forest: This forest forms an intermediate stage combining both tropical and temperate species and covering an altitudinal range of 900-1,800 m. These forests are dominated by species of Ficus, Castanopsis, Callica. In the lower ridges and Sisni, Schima, in the higher ridges whereas in the Kalaktang area, Pinus wallichiana mixed with Rhododendron arboretum, Magnolia, Michelia, Hydrangia, Lyonia, Berberies, Quercus, Rosaceace, etc. are dominant. The valleys of Kalaktang, Rupa, Tenga and Dirang are the abodes of beautiful flowering trees and plants of horticultural value. (b) Temperate forest type: The temperate forests are confined to elevation ranging from 1,800 to 3,500 m. These forests can be divided into two sub types: (i) Temperate broad leaved forests and (ii) Temperate conifer forest. (i) Temperate broad leaved forests: These forests occur between 1,800 to 2,800 m and experience a cold climate and very severe winter with and moderately high rainfall during the monsoon. They are found in Bomdila, Senge, Jang, Tawang Valley and Dirang valley. These forests correspond to the East Himalayan wet temperate forests with dense and, two tiered type. The top canopy is represented by species of tall trees like Quercus lamellose, Q. glauca, Castanopsis spp., Populus ciliata, Rhododendron arboretum, etc Norbu,T., The Monpas of Tawang: Arunachal Pradesh, Department of Cultural Affairs, Directorate of Research, Government of Arunachal Pradesh Itanagar, 2008., pp

23 Figure 2.8 Forest types of the study area Source: A Resource atlas of Arunachal Pradesh, 1999 & Champions and Seth scheme of forest types -45-

24 Table 2.6 Total area under different types of forests Sl. No. Forest Type Total Area (in sq. km.) Percentage 1. Alpine Forest Pine Forest Temperate Forest Sub Tropical Forest Tropical Semi Evergreen Forest Total Source: Generated from forest type map The middle storey is dominated by small to medium sized trees and shrubby species. The common species are Illicium grifithii, Lyonia ovalifolia, Corylopsis himalayana, Myrsine semiserrata, Berberis wallichi, Caryopterris odorata, Debregeasia longifolia, Vaccinium sprengelii, Acer pectinatum, Pyrus polycarpa, Prunus cerasoides, Spiraea arcuata, Symplocos rasimosum, and species of Rhododendron.The ground flora mainly consists of herbaceous species like Anemone elongata, Anaphalis adnata, Begonia nepalensis, Corydalis leptocarpa, Sedum multicaule, Drymaria villosa, Potentilla peduncularis, P. polyphylla, Fragaria nubicola, Cardamine elegantula, Oenanthe javanica, Rorippa indica, Stellaria sikkimensis, S. vesttita, etc. (ii) Temperate conifer forests / Pine forest: These types of forest occur between 2,800 to 3,500 m above temperate broad leaf vegetation and experienced heavy snowfall during winter months. They are also known as East Himalayan mixed coniferous forests. It covers percent in West Kameng and Tawang area. The forest towards the lower limit tends to be mixed coniferous types like Tsuga dumosa, Pinus wallichiana, Rhododendron, Abies spectabilis, Cuppressus torulosa, Taxus wallichiana, Abies delavayi, Picea spinilosa, Larix griffithiana, Abies juniperus. The shrubby layer in such forest is represented by Berberis asiatica, B. wallichiana, Mohonia Spp., Euonymus Spp., Eurya acuminate, Gaultheria fragman, tissima, photinia integrifolia, Vaccinium and -46-

25 Viburnum odoratissimum, etc. The herbaceous flora is mostly seasonal because of heavy snowfall during winter months. Common species are Corydalis pseudolongipes, Cassiope fastigiata, Primula-denticulata, Gaultheria trichophylla, etc. (c) Alpine forest type: This type of vegetation gradually emerges from temperate type at an altitude of 3,000 to 4,500 m and corresponds to alpine pasture, dry alpine scrubs, and dwarf juniper scrubs. In the study area, it covers 20,203 sq. km. which accounts percent of the total area. This type of forest occupies the maximum area. However, between the temperate forests and alpine zone is characterized by trees species like Abies spectabilis, Cupressus torulosa, Juniperus recurva, Larix griffithiana, Pinus wallichiana, Rhododendron Spp., Taxus wallichiana, Tsuga dumosa and shrubs like Berberis asiatica, B. wallichiana, Eurya acuminate, Gaultheria fragmentassima, Photinia intergrifolia, Vaccinium venosum, etc. Abies densa is the dominant conifer with mixed with other conifers like Tsuga dumosa, Taxus baccata, Larix griffithiana and a good variety of small trees and shrubby species of Rhododendron, Berberis, Rosa, Cotoneaster, etc. this range of altitude favours the growth of herbaceous species of Anemone, Aconitum, Cassiope, Primula, Potentilla, Pedicularis, Macanopsis, Coridalis, etc. as small, sometimes stunted, clumps. Towards Sela, about an altitude of 4,200 m, trees gradually disappear, and the rocky slopes are covered with low stunted bushes of Juniperus wallichiana mixed with Rhododendron anthopogon, R. lepidatum and species of Cassiope, Berberis, Sedum, Rheum, etc. on the moss and lichen covered boulders. Beyond the alpine zone, plants lives virtually ceases and only snow capped peaks are found. The Alpine forests cover largest area of the study area with % followed by temperate forest (22.54 %), pine forest (20.58 %) and sub tropical forest (16.07 %). Tropical semi evergreen forest has the -47-

26 lowest share on 12.70% of the study area due to the high altitude location of the area (Table 2.6) Fauna Being covered by temperate and alpine forests, the districts provide an excellent habitat for a wide variety of high altitude wildlife. The mammals recorded in the high altitude of Tawang and West Kameng districts are:- Species Primates: - Tawang macaque, Slow loris, Rhesus macaque. Ungulates:-Barking deer, bharal, chinese goral, himalayan goral, red goral, samber, serow, musk deer, takin and wild pig. Lagomorphs: - Moupin s pika, large eared pika. Pholidota: - Chinese pangolin. Carnivores: - Coloured leopard, common leopard, Himalayan black bear, leopard cat, marbled cat, snow leopard, tiger, wild dog, yellow throated marten, pale weasel, himalayan or masked palm, civet, otter, red panda. Rodents: - Hairy-footed flying squirrel, Himalayan marmot, Himalayan striped squirrel, Orange-bellied Himalayan squirrel, and porcupine. Reptilia: - The available information regarding the occurrence and distribution of the reptilian fauna of Tawang and west Kameng districts are very scanty. The following is a list of reptiles recorded from these regions are Japalura andersonian, Mictopholis, Boiga multifasciata, Rhabdophis Himalaya, Sibinnophis collaris, Trimeresurus monticola and Trimeresurus steinegeri Choudhury S.D., Arunachal Pradesh, District Gazetteers, East Kameng,West Kameng and Tawang Districts,Shillong,1996.,p

27 Fishes are the oldest major group of vertebrates. Fishes found in these two districts are Acrossocheilus hexagonolepis, Barilius bendelisis, Danio aequipinnatus, Garra lamta, Garra nasutus, Labeo dero, Labeo dyocheilus, Oreinus plagiostomus, Neomacheilus beavani, Neomacheilus corica, Neomacheilus rupecola, Ambyceps mangois, Olyra longicaudata, Euchiloglanis hodgarti, Euchiloglanis kamengensis, Pseudecheneis sulcatus and Anabas testudineus. 18 In the lowland alluvial grassy and marshy areas several bird species of babblers, warblers and chats, such as the spotted babbler, the Assam babbler, the red capped babbler, the marshy babbler the bust chat are found. In the perennial water reserve pockets, a variety of birds namely Coots, Jacanas, Teals, Geese, Sandpipers and some game birds such as the Jungles fowl, the Black breasted khaleej, the peacock pheasant, the hornbills, the Green pigeons and the Imperial pigeons are commonly found on fruiting groves. In the montane jungles some typical high altitudinal birds, Asian House Martin, Bar-winged Flycatcher Shrike, Black Bulbul, Black-Drongo, Black Redstart, Black- chinned Yuhina, black-faced laughing thrush, black faced warbler, Black lored Tit, Blood Pheasant, Blue- fronted Redstart, Black throated Tit, Blue-whistling Thrush, Blyth s leaf warbler, Broad- billed Warbler, Brown Hawk owl, Buff-barred Warbler, Chestnut Bellied Nuthatch, Chestnut Bellied Rock Thrush, Chestnut crowned Warbler, Chestnut-Tailed Minla, common Hoopoe, common Lora, common Woodshrike, Crested Serpent Eagle, crimson breasted woodpecker, Cutia, Darjeeling woodpecker, Darkrumped Rosefinch, Emerald Dove, Eurasian-Blackbird, Eurasian Griffon, Eurasian Jay, Eurasian Tree Sparrow, Euraginous Flycatcher, Fire-tailed Sunbird, Golden Bush Robin, 18 Ibid. pp

28 Golden Eagle, Golden-spectacled Warbler, Golden-throated Barbet, Gold-naped Finch, Great Barbet, Great Tit, Green shrike Babbler, Green-backed Tit, Grey Bushchat, Grey Wahtail, Grey-backed Shrike, Grey Crested Tit, Grey headed Bullfinch, Grey- Headed- Canary Flycatcher, Grey-hooded Warbler, Grey-winged Blackbird, Hill-Pigeon, Hill prinia, Himalayan-Griffon, House Swift, Large- billed-crow, Lesser Necklaced Laughing Thrush, Long-tailed Shrike, Long-tailed Thrush, Mistle Thrush, Mountain Imperial- Pigeon, Oriental Hobby, Oriental Turtle- Dove Plumbeous Water Redstart, Red-billed Leiothrix, Red-headed Bullfinch, Red-tailed Minla, Red-vented-Bulbul, Rock bunting, Rufous Sibia, Rufous-necked Laughing Thrush, Rufous- vented Yuhina, Rofous- winged Fulvetta, Rusty- flanked Tree creeper, Scarlet Finch, Scarlet Minivet, Silver-eared Mesia, Speckled Wood Pigeon, Spotted Dove, Spotted Laughing Thrush, Spotted nutcracker, Spot-winged Grosbeak, Streak- breasted Scimitar Babbler, Streaked Laughing Thrush, Striated Laughing Thrush, Stripe-throated Yuhina, Tickell s Leaf Warbler, Ultramarine Flycatcher, Widge-tailed Green-Pigeon, Whiskered Yuhina, White-wagtail, Whitebrowed Rosefinch, White-browed shrike Babbler, White-capped Water-Redstart, Whitecollared Blackbird, White-napped Yuhina, White-spectacled Warbler, Yellow billed Blue Magpie, etc Norbu, T., Op. cit. PP