Here is an essay on ‘Biodiversity in India’ for class 11 and 12. Find paragraphs, long and short essays on ‘Biodiversity in India’ especially written for school and college students.
Essay on Biodiversity in India
- Essay on the Introduction to Biodiversity in India
- Essay on the Magnitude of Biodiversity
- Essay on the Status of Biodiversity in India
- Essay on the Uses and Threats of Biodiversity
- Essay on the Vanishing Wildlife
- Essay on the Causes of Destruction
Essay # 1. Introduction to Biodiversity in India:
Biodiversity encompasses all species of plants, animals, and microorganisms and the ecosystems and ecological processes of which they are parts. It is an umbrella term for the degree of nature’s variety including both the number and frequency of ecosystems, species or genes in a given assemblage. Thus, the term ‘biodiversity’ refers to the totality of ‘genes, species and ecosystems’ of a region.
It is usually considered at three different levels:
(i) Genetic diversity,
(ii) Species diversity, and
(iii) Ecosystem diversity.
(i) Genetic diversity is the sum total of genetic information, contained in the genes of individuals of plants, animals and microorganisms that inhabit the earth.
(ii) Species diversity refers to the variety of living organisms on earth and has been variously estimated to be between 5 and 50 million or more, though only about 1.4 million have actually been described.
(iii) Ecosystem diversity refers to the variety of habitats, biotic communities, and the ecological processes in the biosphere as well as the tremendous diversity within ecosystems in terms of habitat differences and the variety of ecological processes.
Biodiversity is defined as “the variability 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 diversity within species between species and of ecosystems.”
Conservation and sustainable use of biodiversity is fundamental to ecologically sustainable development. Biodiversity is part of our daily lives and livelihood, and constitutes resources upon which families, communities, nations and future generations depend.
Every country has the responsibility to conserve, restore and sustainably use the biological diversity within its jurisdiction. Biological diversity is fundamental to the fulfilment of human needs. An environment rich in biological diversity offers the broadest array of options for sustainable economic ability, for sustaining human welfare and for adapting to change. Loss of biodiversity has serious economic and social costs for any country.
The experience of the past few decades has shown that as industrialisation and economic development in the classical sense have taken place, patterns of consumption, production and needs change, straining, altering and even destroying ecosystems.
India, a megabiodiversity country while following the path of development, has been sensitive to the needs of conservation and, hence, is rich in biological resources. Ethos of conservation and harmonious living with nature is very much ingrained in the lifestyles of India’s people.
Essay # 2. Magnitude of Biodiversity:
The foundation for assessing the importance of biodiversity is an inventory of how many species exist and which species exist where. At the global level the plants and animals are relatively well known. Erwin (1982), for example, suggests as many as 30 million species in total, with most undescribed species living in tropical forests. The known and described number of species of all organisms on the earth is between 1.7 and 1.8 million which is fewer than 15 per cent of the actual number.
About 61 per cent of the known species are insects. Only 4,650 species of mammals are known to biological science. A large number of plant species (2,70,000) and vertebrates are known. But the fact remains that basic knowledge of the organisms that make up most ecosystems, especially in the tropics, is inadequate. Information about bacteria, viruses, protists and Archaea is only fragmentary. For convenience, many assume that about 10 million species exist though the final figure is likely to be 30-50 millions.
Essay # 3. Status of Biodiversity in India:
India occupies only about 2.4 per cent of the world’s land area but its contribution to the world’s biodiversity is approximately 8 per cent of the total number of species which is estimated to be 1.75 million. Of these, 126,188 have been described in India. The species recorded includes flowering plants (angiosperms), mammals, birds, reptiles, amphibians and fishes, constituting 17.3 per cent of the total, whereas nearly 60 per cent of India’s bio wealth is contributed by fungi and insects. Based on the available data, India ranks tenth in the world and fourth in Asia in plant diversity, and ranks tenth in the number of endemic species of higher vertebrates in the world.
There are about 410 species of mammals (8.86% species of the world), about 1,250 species of birds (about 12% of the world species), about 2,546 species of fishes (about 11% of the world species), about 197 species of amphibians (4.4% of the world species), and more than 408 species of reptiles (6% of the world species) are found in India. Among these groups the highest levels of endemism are found in amphibians.
Essay # 4. Uses and Threats of Biodiversity:
Uses of Biodiversity:
Humans derive many direct and indirect benefits from biological diversity. All our food comes from wild species brought into domestication. Most of our medicines, pharmaceuticals, fibres, rubber and timber come from biological resources. The biodiversity also provides many ecological services free of charge that are responsible for maintaining ecosystems. Our water is supplied by one of nature’s most important processes, called the ‘hydrological cycle’. Forested watersheds provide clear, high-quality water for domestic or agricultural use, while healthy rivers provide water, transport and fish.
Threats to Biodiversity:
Major biodiversity threats are as follows:
1. Habitat destruction and fragmentation;
2. Extension of agriculture;
3. Filling up of wetlands;
4. Conversion of rich biodiversity site for human settlement and industrial development;
5. Destruction of coastal areas;
6. Uncontrolled commercial exploitation;
7. Disturbance and pollution; and
8. Introduction of non-native (exotic) species.
Essay # 5. Vanishing Wildlife:
Before the arrival of man about two million years ago, animal species were subjected to natural causes of extinction. A few examples are of extinct ammonites, large cephalopods and brachiopods of Devonian period and dinosaurs of Mesozoic Era. Siwaliks (Himalayan range) were formed in the last and in it are found the largest number of fossils of Tertiary period.
Siwalik fossils include mastodons, hippopotamus, rhinoceros, Sivatherium (large four-horned ruminant), giraffe, horses, camels, bison, deer, antelope, pigs, chimpanzees, orangutans, baboons, langurs, macaques, cheetals, sabre-toothed cats, lions, tigers, sloth bear, Aurochs, leopards, wolves, sholes, porcupines, rabbits, etc.
Many fossil tree species have also been found in the intertrappean beds including Grewioxylon (Eocene) and Heritieroxylon keralensis (middle Miocene) from Kerala and H. arunachalensis (Mio-Pliocene) from Arunachal Pradesh. Grossopteris (fern fossil) was discovered from India and Antarctica led to the discovery of Gondwanaland. Fossil cycads are also found in India.
From Narmada valley was discovered the first dinosaur, Titanosaurus indicus. Another dinosaur fossil from the same area was Rajasaurus narmadensis. Whale fossil Himalayacetus subathuensis was found in Simla hills (Eocene). This area was under water during Tertiary period. Another whale fossil was Remingtonocetus about 43-46 million years old.
During Indus valley civilisation species of wild cattle Bos primegenius nomadicus was vanished. Other mammals which became extinct in India are Indian/Asiatic cheetah, Javan Rhinoceros and Sumatran rhinoceros.
Pink-headed duck (Rhodonessa caryophyllacea) and Himalayan Quail (Ophrysia superciliosa) have became extinct.
The number of species of wild fauna disappeared during the last four centuries are 7 species, 11 species, 27 species and 67 species in seventeenth, eighteenth, nineteenth and twentieth centuries respectively.
Essay # 6. Causes of Destruction:
It is very necessary to access the factors which are hampering in the growth of population of the species such as decimating (death) factors like diseases, predators, etc., or scarcity of food, water and shelter.
Man can easily destroy but cannot create a new species. Forests are unlocked property, it is vast and open and, hence, vulnerable for theft, hunting and killing, poaching, etc. Enormous growth in human population results in conversion of forest into agricultural fields, hunting of wild animals for food, etc. Increase in human population and enhancement in cattle (livestock population) goes side by side which causes adverse effect on wild population.
Pollutants as insecticides, byproducts of industries in the form of gases and water pollutants, quarry of mines, etc., inside forest and such other activities resulting into habitat shrinkage as well as death and disease among the wild animals. Hunting, poaching, killing, smuggling, etc., of wild animals have been hampering and suffering the wild animals. Majority of people are poor and illiterate and are unaware about the importance of wildlife and its role in ecosystem. Wildlife is very much essential for ecobalance and is ultimately essential for human life.
For the existence of an organism/wildlife, food, water and shelter are required. These basic components are exclusively related with wildlife habitats. Wildlife habitats are presently undergoing tremendous changes primarily by the man for his needs, encroachment of forest land for grazing and agricultural purposes due to mushroom growth in human population, constructing roads and cities, etc.
Therefore, man’s manipulation of environment for his needs is the most prevalent factor affecting wildlife habitat and wildlife populations. For instance, in U.S.A., the dense old growth forests may be disastrous to the spotted owl’s nesting and feeding requirements, while it greatly increases preferred forage food for elk.
Destruction of Habitat:
The most serious depletion of wildlife is due to habitat destruction. Habitats which protect wildlife are being converted for human settlements, harbours, dams, reservoirs, croplands, grazing grounds, mining operations, etc. Environmental pollution and deforestation have also caused the degradation of important habitats.
Migratory animals are also vulnerable to the destruction of habitats because disturbance at any point of their migratory routes affects them. Some of the dams are blocking spawning, migration of fishes by inundating habitats and by altering the physical environment. Many species of whales, sea cows and sea turtles are facing total extinction as they are caught by mechanical devices for the sea industry.
Vultures and kites feed on carcases. Since carcases are being buried or burnt now, the population of large flying bird, California condor (Gymnogyps californianus) has started declining.
Asiatic wild ass (Asinus hemionus khur) in Rann of Kutch, Indian lion, musk deer, etc., are facing danger of imminent extinction due to reduction of habitat.
In wild animals, there are a number of diseases which are decimating factors and cause a lot of loss of wild animals. It is also very difficult to diagnose and treat the disease in wild animals because they are free ranging animals. Khera (1980) pointed out that the prevalence of epizootic diseases among wildlife has also been a major factor associated with decline in number of some species of wildlife population.
Important diseases found in wild animals are as follows:
1. Foot and Mouth disease (FMD) caused by Picorna virus mostly occurring in wild boar, cheetal, sambhar and gaur (hoofed mammals).
2. Rinderpest caused by Paramyxo virus found in ruminants such as cattle, cheetal, sambhar, gaur and wild buffalo, etc. It also infects wild animals through the cattle.
3. Anthrax caused by Bacillus anthrasis (bacteria) found in mammals (enlargement of spleen).
4. Brucellosis caused by Brucella bacteria found in cattle, cheetal, sambhar, etc. It causes tumor in the joints.
5. Botulism a kind of paralysis caused by Clostridium botulinum (bacteria). It makes the food poisonous. It occurs in aquatic birds.
6. Tuberculosis caused by Bacterium tuberculosis. It is found in wild animals like human beings. It is also common in monkeys.
7. Rabies caused by Rhabdo virus. It is very common in pet dogs and street dogs, wolf, jackal, fox, jungle cat, mongoose, etc.
8. Distemper caused by Paramyxo virus. It is found in carnivorous mammals. Fever affects central nervous system.
Adverse climatic conditions also cause casualty in wild animals such as very hot weather, excessive rainfall and cold, flood, earthquake, volcano, etc. The population having excessive number than the carrying-capacity is more liable to death. Such deaths can be minimised by increasing carrying capacity, food, water and shelter.
Fire, flood, earthquake and road crossing, etc., also cause their accidental death. In forest fire, many wild animals, their young ones, eggs, shelter are burnt. Such accidents can be avoided or minimised by proper management.
Wild animals are also killed by poisoning by man to save agricultural crops and cattle, etc.
Illegal hunting of wild animals by man is also to be checked. It is done by smugglers and local people living inside forest or neighbouring forest. It causes heavy loss in wild populations.