STUDY AREA. Geo-Ecological setting of the study site:

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1 STUDY AREA Geo-Ecological setting of the study site: The Manipur State is located in the mid of highly diverse Biological region of the Indo- Burma mega diversity Hot-spot zone of the world. The area is identified as the zone of confluence of three major species streams namely the Malayo-Polynesian species, the Tibeto- Chinese species and the Indian sub-continent species. This area is not only the abode of the highly diversified and endemic species but also home of the thirty-eight communities living with indigenous knowledge systems. The state lies in between the 23.83º N to 25.68º N latitudes and 93.03º E to 94.78º E longitudes with a geographical area of about 22,372 Sq. Km. (Table-1). Topologically more than 80 percent of the state of Manipur, covering a surface area of 22,327 Sq. Km, constitutes a series of mountain and hill ranges, while a tectonic valley located centrally. The highest peak, Mount Iso, stand at 2,997meters above the mean sea level with its highest inter-mountain valley of Dzuko at 2,500 meters. The Barak valley including Jiri-plain and the foothill areas of the Kyam Tampak (Kabaw valley) represent the lowest elevated areas of the state at 25 to 30 meters above MSL. In between the lowest elevated and the highest elevated areas of the state, a series of varied topographic distinctions are naturally exhibited in association with varied micro-climatic evidences. As a result, the state is harbouring a variety of endemic bio-diversity and it is said that the state is located in the trijunction where the Himalayan flora and fauna are available in abundance. Manipur forms a part of the global bio-diversity hotspot. A wide variety of habitats exist in the state-ranging from low lying swamps and marshy lands to tropical wet-evergreen, semi-evergreen and a few moist deciduous forests in the lower hilly regions. Sub-tropical, broad leaf and pine clothe to savanna type grass lands are at the upper reaches of the mountain range. The natural vegetation of the state, as that of any mountainous region within the monsoon belt, varies with changes in the topographic landscape features, altitudes and soils. Thus, varieties of flora varying from aquatic to those growing on the high altitudes are found in this part of the globe. About half of the area comprises of tropical evergreen and semi-evergreen forests. Pine forests cover about the sixth part of the area, and large stretches of bamboo forests cover about a fifth of the region. Abandoned jhum fields are also part of 5

2 the forests of Manipur. In these different forest areas different endemic bio-species, at least 100 species of mammals and over 400 species of avifaunal species, many of which are extremely rare and endangered, are found (Ranjan, 2000). Geo-technically and naturally the valley of Manipur was endowed with a number of wetlands where the maximum numbers of endemic aquatic bio-diversities are found observed. Among these the Loktak Pat (lake) is known for its (recently documented) biospecies numbering 265 species of flora and 425 species of fauna (i.e.249 vertebrate & 176 invertebrates). These faunal species comprise of 116 avifaunal species including 21 species of waterfowl that are migratory; 64 fishes, 32 mammal and 6 amphibian species. Current reports have observed more than 233 species of microphytes and 32 species of phytoplankton as the aquatic flora in the Loktak Lake. These are, of course, some of the records of the recent research and documentation activity. However, it is believed that a number of species and subspecies of flora and fauna of the Loktak may have already become extinct. The present day developmental planning and power generation probably are not friendly to wetland ecosystem of the state. Therefore, the rare, endangered and endemic bio-species in the state are under constant threats. It has been a shocking affair how the condition of the Loktak Pat and other adjoining wetlands have deteriorated rapidly. Drainage System: It is also interesting to note that the state belongs to the region of the world s heaviest rainfall region. Currently the state receives 142 cm. of annual rainfall. It receives rains during the summer monsoon, from the middle of June to September. During these four months, it receives 60% of the total annual rainfall. All the drainage systems of Manipur are rain fed one. There are two major Trans Boundary Rivers originated from the state. They are namely the Manipur River and the Barak River. The Manipur River is one of the major head streams of the Chindwin River of the Irrawaddy drainage system of Myanmar. River System of Manipur: The eastern half of the state has been predominantly drained by the Manipur River (head of the Chindwin River) and its tributaries. The sub-drainage system of the Manipur River consists of two sub-groups of tributaries i.e. (a) tributaries directly discharged to the Manipur River and (b) those tributaries emptied into the Loktak Lake and otter valley wetlands. The Iril, Imphal, Thoubal, Chakpi, the Khuga are the first group of tributaries while the Numbul, 6

3 the Nambol, Thongjaorok, the Ningthoukhong, the Moirang turel etc. are the second group of tributaries of the Manipur River draining an area of about 800 Sq. Km. Barak River System : The Barak System consists of mainly seven major tributaries within the zone of the state. They are namely the Makru, Irang, Tuivai, Jiri, etc. The system is draining the basin area of about 9,518 Sq. Km. Other Sub-System : There are another sub-drainage system is also prevailing in the eastern border areas of the state, they are Tezu and Yu River. Forest and vegetation : However, for the present study the scholar has tried to classify the hilly regions of the state into five major types of forests. The classification is sharply stratified by altitude. They are (1) Wet Temperate Forest, (2) Pine Forest, (3) Wet-sub-tropical Hill Forest, (4) Semi Evergreen Forest and (5) Teak-Gurjan Forest. Similarly the Valley region has also been classified into four major vegetation zones viz. (1) Mixed open scrub and scattered tree, (2) Swamp-vegetation, (3) Grasses and herbs and (4) Mixed Riverine forests. They are namely the Manipur River and the Barak River. The Manipur River is one of the major Head streams of the Chindwin River of the Irrawaddy drainage system of Myanmar.. 7

4 N a Fig.1.(a) Map of India, showing location of Manipur. 1(b): Map of Manipur showing study site. b Fig.-1. (a): Map of India showing Manipur. ; Fig.-1. (b): Map of Manipur showing the study site. 8

5 River system of Manipur: The eastern half of the state has been predominantly drained by the Manipur River (head of the Chindwin River) and its tributaries. The sub-drainage system of the Manipur River consists of two sub-groups of tributaries i.e. (a) tributaries directly discharged to the Manipur River and (b) those tributaries emptied into the Loktak Lake and other valley wetlands. The Iril, the Imphal, the Thoubal, the Chakpi, the Khuga are the first group of tributaries of the Manipur River draining an area of about 800 Sq. Km. Barak River system: The Barak river System consists of mainly seven major tributaries within the zone of the state. They are namely the Makru, Irang, Tuivai, Jiri, etc. The system is draining the basin area of about 9,518 Sq. Km. Other Sub-System: There are other sub-drainage systems, which are prevailing in the eastern border areas of the state, they are the Tezu and the Yu River. Hill zones: 1) Wet Temperate Forest- These forests are localized at an elevation of 1,700 to 2, 700 meters above the sea level. The plant species found are Quercus serrata Thunb., Michelia champaca L., Acer laevigatum Wall., Magnolia griffithii Hook.f. & Thomson etc. It covers an area of about 1450 Sq. Km. 2) Pine Forest- This type of forest is found in the north-eastern and southern parts of the state. It lies at an average altitude of 900 to 1800 meters above sea level and covers an area of about 2,440 Sq. Km. Most of the plant species observed are of Pinus khashia Engelm. along with Quercus serrata Thunb. and Castanopsis armata Spach. 3) Wet-Sub-Tropical Hill Forest: It stretches at an elevation of about 900 to 1800 meters above mean sea level covering an area of about 6,590 Sq. Km. Predominant plant species found are Machilus bombycina King ex Hook.f. Schima wallichii Choisy, and Quercus serrata Thunb. etc. Hill Forest: 9

6 Semi-Evergreen Forest: From the foot-hill zones up to 900 meters above the mean sea level this type of forest is found. This type is gregariously grown in the western part of the state adjoining the Barak Valley of Assam. Artocarpus lakoocha Roxb., Phoebe attenuate Nees, Toona ciliata M. Roem., Gmelina arborea Roxb., Schima wallichii Choisy etc. are the common species of the region. This region covers an area of about 645 Sq. Km. and has been subjected to heavy shifting cultivation practices. Teak Gurjan Forest: This type of forest is commonly found along the border zone of the Indo-Myanmar at the same altitudinal zone of the semi-evergreen forest. It covers an area of about 510 Sq. Km. Valley Region: (1) Mixed open scrub and scattered tree- This type of vegetation occupy the foot-hills and hillocks of the valley region. It covers an area of about 1009 Sq. Km. Some of the important species are Calophyllum polyanthus Wall. ex Choisy, Castanopsis armata Spach., Phoebe attenuate Nees, Bombax ceiba L., Pinus khasya Royle ex Gord.and Thea sinensis L. etc. Swamp vegetation- The aquatic and swamp vegetation abound the lakes, swamps and marshes which covers an area of about 434 Sq. Km. Water hyacinth, water lily and many other species of plant belonging to the family of Nymphaeaceae, Euryale ferox Salisb. and Nelumbo nucifera Gaertn. are found in this group. Certain species like Trapa natans L., Cyperus rotundus L., Sagittaria sagittifolia L., and Zizania latifolia Turcz. ex Stapf. and under-ground rhizomes of lotus are used as one of the delicious food items. Grasses and Herbs- The areas around the lakes and marshes and the peripheral plain area bordering the foot-hills are covered with grasses and herbs. It covers an area of about 30 Sq. Km. Reeds, tall grasses and various medicinal and edible herbs including Persicaria barbatum (L.) Hara, Plumbago zeylanica L., Centella asiatica (L.) Urban etc. are some of the common species available in this region. Riverine forest of Mixed type- Most of the river banks, flood-plains and area around the villages support a type of mixed evergreen and deciduous vegetation containing Bambusa natans Wall., Ficus benghalensis L., Mangifera indica L. etc. It covers an area of about 27 Sq. Km. 10

7 Though the state enjoys a fair degree of uniform climatic condition, it has varying landscapes with different micro-climatic conditions clad with diverse flora as stated earlier. Similarly the area supports a variety of faunal species. The phyla of animal are part and parcel of the forest complex and water bodies of the state. Thus, any form of destruction in the plant kingdom has a corresponding effect on the faunal diversity. The avian-faunal species of the area are those common to other parts of the country. However, varied game birds the seasonally migrate in the wetlands of the valley and the inter-mountain wetlands. One of the rarest species of mammal, brow antlered deer popularly known as Sangai is found in the Keibul Lamjao Reserve forest. 11