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Biodiversity in India - Part 1
1.0 INTRODUCTION
Biodiversity refers to the variety & differences among living organisms from all sources, including terrestrial, marine, and other aquatic ecosystems and the ecological complexes of which they are a part. This includes genetic diversity within and between species and of ecosystems. Thus, in essence, biodiversity represents all life. India is one of the mega biodiversity centres in the world and has two of the world's 18 'biodiversity hotspots' located in the Western Ghats and in the Eastern Himalayas (Myers 1999). The forest cover in these areas is very dense and diverse and of pristine beauty, and incredible biodiversity.
Over the past 100 years, a lot of damage has been done to the earth’s biodiversity. Increasing human population, increasing consumption levels, and decreasing efficiency of use of our resources are some of the causes that have led to overexploitation and manipulation of ecosystems. Illegal trade in wildlife, such as rhino horn, has led to the extinction of species. Consequences of biodiversity loss can be great as any disturbance to one species gives rise to imbalance in others.
What is biodiversity : This term is used by to refer to all aspects of variability evident within the living world, including diversity within and between individuals, populations, species, communities, and ecosystems. Differences in pest resistance among rice varieties, the range of habitats within a forest ecosystem, or the global extinction of species of lake fish, all illustrate different aspects of biological diversity. The term is commonly used loosely to refer to all species and habitats in some given area, or even on the Earth overall.
The biosphere : The part of the planet occupied by living organisms can be pictured as a thin and irregular envelope around the Earth's surface, at most just a few kilometres deep on the globe's radius of more than 6000 km. Because most organisms depend directly or indirectly on sunlight, the regions reached by sunlight form the core of the biosphere: i.e. the land surface, the top few millimetres of the soil, and the upper waters of lakes and the ocean. Bacteria occur almost everywhere, even kilometres deep within the Earth's rocky crust. Active living organisms are usually absent where liquid water is absent, but the dormant spores of bacteria and fungi are ubiquitous, from polar icecaps to many kilometres above the surface of the Earth.
The sacred groves of India are some of the areas in the country where the richness of biodiversity has been well preserved. The Thar desert and the Himalayas are two regions rich in biodiversity in India. There are 103 national parks & 535 wildlife sanctuaries in the country, and the government is very serious about protecting the biodiversity of India.
2.0 GEOGRAPHICAL FEATURES OF INDIA
As one of the world’s largest nations, India occupies a prime position in discussions on biodiversity. It is the seventh largest country in the world and Asia's second largest nation with an area of 32,87,263 square km. The Indian mainland stretches from 8° 4' to 37° 6' N latitude and from 68° 7' to 97° 25' E longitude. It has a land frontier of some 15,200 kms and a coastline of 7,516 kms (Government of India, 1985). India's northern frontiers are with Xizang (Tibet) in the Peoples Republic of China, Nepal and Bhutan. In the north-west, India borders on Pakistan; in the north-east, China and Burma; and in the east, Burma. The southern peninsula extends into the tropical waters of the Indian Ocean with the Bay of Bengal lying to the south-east and the Arabian Sea to the south-west. For administrative purposes India is divided into 29 states and 7 union territories. The country is home to around 1300 million people, about 18% of the World's population.
Physically, India is divided into four relatively well defined regions - the Himalayan mountains, the Gangetic river plains, the southern (Deccan) plateau, and the islands of Lakshadweep, Andaman and Nicobar. The Himalayas in the far north include some of the highest peaks in the world. The highest mountain in the Indian Himalayas is Khangchenjunga (8586 m) which is located in Sikkim on the border with Nepal. To the south of the main Himalayan massif lie the Lesser Himalaya, rising to 3,600-4,600 m, and represented by the Pir Panjal in Kashmir and Dhauladhar in Himachal Pradesh. Further south, flanking the Indo-Gangetic Plain, are the Shivaliks (mountains) which rise to 900-1,500 m.
The northern plains of India stretch from Assam in the east to the Punjab in the west (a distance of 2,400 km), extending south to terminate in the saline swamplands of the Rann of Kachchh (Kutch), in the state of Gujarat. Some of the largest rivers in India including the Ganga (Ganges), Ghaghara, Brahmaputra, and the Yamuna flow across this region. The delta area of these rivers is located at the head of the Bay of Bengal, partly in the Indian state of west Bengal but mostly in Bangladesh. The plains are remarkably homogenous topographically: for hundreds of kilometres the only perceptible relief is formed by floodplain bluffs, minor natural levees and hollows known as 'spill patterns', and the belts of ravines formed by gully erosion along some of the larger rivers. In this zone, variation in relief does not exceed 300 m (FAO/UNEP, 1981) but the uniform flatness conceals a great deal of pedological variety. The agriculturally productive alluvial silts and clays of the Ganga-Brahmaputra delta in north-eastern India, for example, contrast strongly with the comparatively sterile sands of the Thar Desert which is located at the western extremity of the Indian part of the plains in the state of Rajasthan.
As is well known, the climate of India is dominated by the Asiatic monsoon, most importantly by rains from the south-west between June and October, and drier winds from the north between December and February. From March to May the climate is dry and hot.
3.0 BIODIVERSITY OF INDIA
3.1 Wetlands
India’s variety of wetland habitats is a rich one. The total area of wetlands in India is 15.26 million hectares, or 4.63% of the country. Two sites - Chilika Lake (Orissa) and Keoladeo National Park (Bharatpur) - have been designated under the Convention of Wetlands of International Importance (Ramsar Convention) as being especially significant waterfowl habitats. The country's wetlands are generally differentiated by region into eight categories (Scott, 1989): the reservoirs of the Deccan Plateau in the south, together with the lagoons and the other wetlands of the southern west coast; the vast saline expanses of Rajasthan, Gujarat and the gulf of Kachchh; freshwater lakes and reservoirs from Gujarat eastwards through Rajasthan (Kaeoladeo Ghana National park) and Madhya Pradesh; the delta wetlands and lagoons of India's east coast (Chilka Lake); the freshwater marshes of the Gangetic Plain; the floodplain of the Brahmaputra; the marshes and swamps in the hills of north-east India and the Himalayan foothills; the lakes and rivers of the montane region of Kashmir and Ladakh; and the mangroves and other wetlands of the island arcs of the Andamans and Nicobars.
3.2 Forests
India’s natural ecosystems give it a distinct identity. Furthermore, its geography, history and culture add to it. The panorama of Indian forests ranges from evergreen tropical rain forests in the Andaman and Nicobar Islands, the Western Ghats, and the north-eastern states, to dry alpine scrub high in the Himalaya to the north. Between the two extremes, the country has semi-evergreen rain forests, deciduous monsoon forests, thorn forests, subtropical pine forests in the lower montane zone and temperate montane forests.
One of the most important tropical forests classifications was developed for Greater India and later republished for present-day India. This approach has proved to have wide application outside India. In it 16 major forests types are recognised, subdivided into 221 minor types. Structure, physiognomy and floristics are all used as characters to define the types.
The main areas of tropical forest are found in the Andaman and Nicobar Islands; the Western Ghats, which fringe the Arabian Sea coastline of peninsular India; and the greater Assam region in the north-east. Small remnants of rain forest are found in Orissa state. Semi-evergreen rain forest is more extensive than the evergreen formation partly because evergreen forests tend to degrade to semi-evergreen with human interference. There are substantial differences in both the flora and fauna between the three major rain forest regions.
The Western Ghats Monsoon forests occur both on the western (coastal) margins of the ghats and on the eastern side where there is less rainfall. These forests contain several tree species of great commercial significance (e.g. Indian rosewood Dalbergia latifolia, Malabar Kino Pterocarpus marsupium, teak and Terminalia crenulata), but they have now been cleared from many areas. In the rain forests there is an enormous number of tree species. At least 60 percent of the trees of the upper canopy are of species which individually contribute not more than one percent of the total number. Clumps of bamboo occur along streams or in poorly drained hollows throughout the evergreen and semi-evergreen forests of south-west India, probably in areas once cleared for shifting agriculture.
The tropical vegetation of north-east India (which includes the states of Assam, Nagaland, Manipur, Mizoram, Tripura and Meghalaya as well as the plain regions of Arunachal Pradesh) typically occurs at elevations up to 900 m. It embraces evergreen and semi-evergreen rain forests, moist deciduous monsoon forests, riparian forests, swamps and grasslands. Evergreen rain forests are found in the Assam Valley, the foothills of the eastern Himalayas and the lower parts of the Naga Hills, Meghalaya, Mizoram, and Manipur where the rain fall exceeds 2300 mm per annum. In the Assam Valley the giant Dipterocarpus macrocarpus and Shorea assamica occur singly, occasionally attaining a girth of up to 7 m and a height of up to 50 m. The monsoon forests are mainly moist sal Shorea robusta forests, which occur widely in this region (IUCN, 1991).
The Andamans and Nicobar islands have tropical evergreen rain forests and tropical semi-evergreen rainforests as well as tropical monsoon moist monsoon forests (IUCN, 1986).The tropical evergreen rain forest is only slightly less grand in stature and rich in species than on the mainland. The dominant species is Dipterocarpus grandiflorus in hilly areas, while Dipterocarpus kerrii is dominant on some islands in the southern parts of the archipelago. The monsoon forests of the Andamans are dominated by Pterocarpus dalbergioides and Terminalia spp.
3.3 Marine environment
India is not found wanting in terms of fishing potential. The nearshore coastal waters of India are extremely rich fishing grounds. The total commercial marine catch for India has stabilised over the last ten years at between 1.4 and 1.6 million tonnes, with fishes from the clupeoid group (e.g. sardines Sardinella sp., Indian shad Hilsa sp. and whitebait Stolephorus sp.) accounting for approximately 30% of all landings. In 1981 it was estimated that there were approximately 180,000 non-mechanised boats (about 90% of India's fishing fleet) carrying out small-scale, subsistence fishing activities in these waters. At the same time there were about 20,000 mechanised boats and 75 deep-sea fishing vessels operating mainly out of ports in the states of Maharashtra, Kerala, Gujarat, Tamil Nadu and Karnataka.
Many of us have read about the famous Australian Great Barrier Reef. In India too, coral reefs occur, but along only a few sections of the mainland, principally the Gulf of Kutch, off the southern mainland coast, and around a number of islands opposite Sri Lanka. This general absence is due largely to the presence of major river systems and the sedimentary regime on the continental shelf. Elsewhere, corals are also found in Andaman, Nicobar, and Lakshadweep island groups although their diversity is reported to be lower than in south-east India (UNEP/IUCN, 1988).
Indian coral reefs have a wide range of resources which are of commercial value. Exploitation of corals, coral debris and coral sands is widespread on the Gulf of Mannar and Gulf of Kutch reefs, while ornamental shells, chanks and pearl oysters are the basis of an important reef industry in the south of India. Sea fans and seaweeds are exported for decorative purposes, and there is a spiny lobster fishing industry along the south-east coast, notably at Tuticorin, Madras and Mandapam Commercial exploitation of aquarium fishes from Indian coral reefs has gained importance only recently and as yet no organised effort has been made to exploit these resources. Reef fisheries are generally at the subsistence level and yields are unrecorded.
Other notable marine areas are seagrass beds, which although not directly exploited are valuable as habitats for commercially harvested species, particularly prawns, and mangrove stands. In the Gulf of Mannar the green tiger prawn Penaeus semisulcatus is extensively harvested for the export market. Seagrass beds are also important feeding areas for the dugong Dugong dugon, plus several species of marine turtle.
Turtles have given rise to a lot of heated debate indeed! Five species of marine turtle occur in Indian waters: Green turtle Chelonia mydas, Loggerhead Caretta caretta, Olive Ridley Lepidochelys olivacea, Hawksbill Eretmochelys imbricata and Leatherback Dermochelys coriacea. Most of the marine turtle populations found in the Indian region are in decline. The principal reason for the decrease in numbers is deliberate human predation. Turtles are netted and speared along the entire Indian coast. In south-east India the annual catch is estimated at 4,000-5,000 animals, with C. mydas accounting for about 70% of the harvest. C. caretta and L. olivacea are the most widely consumed species. E. imbricata is occasionally eaten but it has caused deaths and so is usually caught for its shell alone. D. coriacea is boiled for its oil which is used for caulking boats and as protection from marine borers. Incidental netting is widespread. In the Gulf of Mannar turtles are still reasonably common near seagrass beds where shrimp trawlers operate, but off the coast of Bengal the growing number of mechanized fishing boats has had the effect of increasing incidental catch rates.
4.0 Species Diversity
India contains a great wealth of biological diversity in its forests, its wetlands and in its marine areas. This richness is shown in absolute numbers of species and the proportion they represent of the world total
India has a great many scientific institutes and university departments interested in various aspects of biodiversity. A large number of scientists and technicians have been engaged in inventory, research, and monitoring. The general state of knowledge about the distribution and richness of the country's biological resources is therefore fairly good.
4.1 Endemic species
Endemic means native. India has many endemic plant and vertebrate species. Among plants, species endemism is estimated at 33% with 140 endemic genera but no endemic families (Botanical Survey of India, 1983). Areas rich in endemism are north-east India, the Western Ghats and the north-western and eastern Himalayas. A small pocket of local endemism also occurs in the Eastern Ghats (MacKinnon & MacKinnon, 1986). The Gangetic plains are generally poor in endemics, while the Andaman and Nicobar Islands contribute at least 220 species to the endemic flora of India (Botanical Survey of India, 1983).
WCMC's Threatened Plants Unit (TPU) is in the preliminary stages of cataloguing the world's centres of plant diversity; approximately 150 botanical sites worldwide are so far recognised as important for conservation action, but others are constantly being identified (IUCN, 1987). Five locations have so far been issued for India: the Agastyamalai Hills, Silent Valley and New Amarambalam Reserve and Periyar National Park (all in the Western Ghats), and the Eastern and Western Himalaya.
Endemism among mammals and birds is relatively low. Only 44 species of Indian mammal have a range that is confined entirely to within Indian territorial limits. Four endemic species of conservation significance occur in the Western Ghats. They are the Lion-tailed macaque Macaca silenus, Nilgiri leaf monkey Trachypithecus johni (locally better known as Nilgiri langur Presbytis johnii), Brown palm civet Paradoxurus jerdoni and Nilgiri tahr Hemitragus hylocrius.
Only 55 bird species are endemic to India, with distributions concentrated in areas of high rainfall. They are located mainly in eastern India along the mountain chains where the monsoon shadow occurs, south-west India (the Western Ghats), and the Nicobar and Andaman Islands (ICBP, 1992).
In contrast, endemism in the Indian reptilian and amphibian fauna is high. There are around 187 endemic reptiles, and 110 endemic amphibian species. Eight amphibian genera are not found outside India. They include, among the caecilians, Indotyphlus, Gegeneophis and Uraeotyphlus; and among the anurans, the toad Bufoides, the microhylid Melanobatrachus, and the frogs Ranixalus, Nannobatrachus and Nyctibatrachus. Perhaps most notable among the endemic amphibian genera is the monotypic Melanobatrachus which has a single species known only from a few specimens. It is possibly most closely related to two relict genera found in the mountains of eastern Tanzania.
4.2 Threatened species
India contains 172 species of animal considered globally threatened by IUCN, or 2.9% of the world's total number of threatened species (Groombridge, 1993). These include 53 species of mammal, 69 birds, 23 reptiles and 3 amphibians. India contains globally important populations of some of Asia's rarest animals, such as the Bengal Fox, Asiatic Cheetah, Marbled Cat, Asiatic Lion, Indian Elephant, Asiatic Wild Ass, Indian Rhinoceros, Markhor, Gaur, Wild Asiatic Water Buffalo etc.
A workshop indicated that as many as 3,000-4,000 higher plants may be under a degree of threat in India. Since then, the Project on Study, Survey and Conservation of Endangered species of Flora (POSSCEP) has partially documented these plants, and published its findings in Red Data Books.
5.0 Protected Areas Network
5.1 Development and history
India has had a long tradition of protection of wildlife. Wise use of natural resources was a prerequisite for many hunter-gatherer societies which date back to at least 6000 BC. Extensive clearance of forests accompanied the advance of agricultural and pastoral societies in subsequent millennia, but an awareness of the need for ecological prudence emerged and many so-called pagan nature conservation practices were retained. As more and more land became settled or cultivated, so these hunting reserves increasingly became refuges for wildlife. Many of these reserves were subsequently declared as national parks or sanctuaries, mostly after Independence in 1947. Examples include Gir in Gujarat, Dachigam in Jammu & Kashmir, Bandipur in Karnataka, Eravikulum in Kerala, Madhav (now Shivpuri) in Madhya Pradesh, Simlipal in Orissa, and Keoladeo, Ranthambore and Sariska in Rajasthan.
Wildlife, together with forestry, has traditionally been managed under a single administrative organisation within the forest departments of each state or union territory, with the role of central government being mainly advisory. There have been two recent developments. First, the Wildlife (Protection) Act has provided for the creation of posts of chief wildlife wardens and wildlife wardens in the states to exercise statutory powers under the Act. Under this Act, it is also mandatory for the states to set up state wildlife advisory boards. Secondly the inclusion of protection of wild animals and birds in the concurrent list of the constitution, has proved the union with some legislative control over the states in the conservation of wildlife. The situation has since improved, all states and union territories with national parks or sanctuaries having set up wildlife wings.
The adoption of a National Policy for Wildlife Conservation in 1970 and the enactment of the Wildlife (Protection) Act in 1972 lead to a significant growth in the protected areas network, from 5 national parks and 60 sanctuaries to 69 and 410 respectively, in 1990.
The network was further strengthened by a number of national conservation projects, notably Project Tiger, initiated in April 1973 by the Government of India with support from WWF and the crocodile Breeding and Management Project, launched on 1 April, 1975 with technical assistance from UNDP/FAO.
5.2 Protected areas of the Western Ghats
The Western Ghats are a chain of highlands running along the western edge of the Indian subcontinent, from Bombay south to the southern tip of the peninsula, through the states of Maharashtra, Karnataka, Kerala and Tamil Nadu. Covering an estimated area of 159,000 sq. km, the Western Ghats are an area of exceptional biological diversity and conservation interest, and are "one of the major Tropical Evergreen Forest regions in India". As the zone has already lost a large part of its original forest cover (although timber extraction from the evergreen reserve forests in Kerala and Karnataka has now been halted) it must rank as a region of great conservation concern. The small remaining extent of natural forest, coupled with exceptional biological richness and ever increasing levels of threat (agriculture, reservoir flooding plantations, logging and over exploitation), are factors which necessitate major conservation inputs.
There are currently seven national parks in the Western Ghats with a total area of 2,073 sq. km (equivalent to 1.3% of the region) and 39 wildlife sanctuaries covering an area of about 13,862 sq. km (8.1%).
The management status of the wildlife sanctuaries in this part of India varies enormously. Tamil Nadu's Nilgiri wildlife sanctuary, for example, has no human inhabitants, small abandoned plantation areas and no produce exploitation, while the Parambikulam wildlife sanctuary in Kerala includes considerable areas of commercial plantations and privately owned estates with heavy resource exploitation.
6.0 International Programmes and Conventions
India participates with many international agreements and programmes concerned with aspects of nature conservation and sustainable development. These range from legal instruments such as the Convention on Biological Diversity, which place obligations on those nations which become contracting parties, to scientific programmes such as the UNESCO Man and the Biosphere Programme, a global programme of international scientific cooperation. Examples of agreements and programmes with which India is collaborating include:
Convention on International Trade in Endangered Species (CITES): Since India became a party to CITES on 18th October 1976 it has provided data annually to the CITES secretariat on the trade of endangered species through its CITES Management Authority. The text of the CITES convention along with the CITES appendices are provided.
6.1 World Heritage Convention
India ratified the World Heritage Convention in 1977 and since then five natural sites have been inscribed as areas of 'outstanding universal value'. These sites are: Kaziranga National Park, Keoladeo National Park, Manas National Park, Sundarbans National Park, and Nanda Devi National Park.
6.2 Convention on Biological Diversity
India signed the Convention on Biological Diversity on 5th June 1992, ratified it on 18th February 1994 and brought it into force on 19th May 1994. This convention will provide a framework for the sustainable management and conservation of India's natural resources.
6.3 Ramsar (Wetlands) Convention
India has been a contracted party to the Ramsar Convention since 1st February 1982. India has now six sites covering some 1,92,973 hectares of important wetlands. These sites are: Chilika Lake, Keoladeo National Park, Wular Lake, Harike Lake, Loktak Lake, and Sambhar Lake.
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