The Earth’s biodiversity is evenly distributed across its surface. There are over a thousand major eco-regions in the world. It is estimated that there are about 200 richest, rarest and most distinctive natural areas in the world. These are referred to as the Global 200.
Hotspots of biodiversity refer to bio-geographic regions where significant levels of biodiversity with richness and unusual concentration of endemic species are found, however, they are threatened with mindless exploitation and destruction.
A biodiversity is termed as a hotspot if −
· It has at least 1,500 vascular plants as endemic.
· It must be threatened or under threat of destruction to a considerable extent.
Across the world, about 35 areas are marked as hotspots of biodiversity and they represent 2.3 percent of the Earth’s land surface but they support more than half of the world’s endemic plant species and almost half of birds, mammals, reptiles, and amphibians as endemic.
North and Central America − California Floristic Province, Madrean pine-oak woodlands, Mesoamerica
The Caribbean − Caribbean Islands
South America − Atlantic Forest, Cerrado, Chilean Winter Rainfall-Valdivian Forests, Tumbes-Chocó-Magdalena, Tropical Andes
Europe − Mediterranean Basin
Africa − Cape Floristic Region, Coastal Forests of Eastern Africa, Eastern Afromontane, Guinean Forests of West Africa; Horn of Africa; Madagascar and the Indian Ocean Islands; Maputaland-Pondoland-Albany; Succulent Karoo
Central Asia − Mountains of Central Asia
South Asia − Eastern Himalaya, Nepal; Indo-Burma, India and Myanmar; Western Ghats, India; Sri Lanka
South East Asia and Asia-Pacific − East Melanesian Islands; New Caledonia; New Zealand; Philippines; Polynesia-Micronesia; Southwest Australia; Sundaland; Wallacea
East Asia − Japan; Mountains of Southwest China
West Asia − Caucasus; Irano-Anatolian
About 1.8 million species are known to mankind at present. Scientists, however, have estimated that the number of species of plants and animals on the earth can go up to 20 billion. It means a majority of species still remain undiscovered.
World’s most prolific bio-rich nations are in the south. On the other hand, the majority of the countries capable of exploiting biodiversity are the developed Northern countries. These countries have very low level of biodiversity.
Developed nations want to consider biodiversity as ‘global resources’. However, nations rich in biodiversity like India don’t want to compromise their sovereignty over their biological diversity unless there is a revolutionary change in global thinking about sharing of all types of natural resources such as rare minerals as uranium, oil, or even intellectual and technological resources.
India is home to rich biodiversity. Countries with diversities higher than India are located in South America such as Brazil, and South East India countries such as Malaysia and Indonesia.
Biological diversities are now being increasingly appreciated as being of unimaginable value. International initiatives such as World Heritage Convention, Biodiversity Action Plan (BAP) aims for the protection and support of biologically rich natural areas and address threatened species and habitats to protect and restore biological systems.
Convention in the Trade of Endangered Species (CITES) is intended to reduce the utilization of endangered plants and animals by controlling trade in their products and in pet trade.
A mega diversity region or country is one that harbors majority of the Earth’s species and is therefore considered extremely bio-diverse. India is rich in biodiversity from north to south and from east to west. Geological events in the landmass of India, different climatic regions across the country and its special geographical position between a couple of distinct biological evolution and radiation of species are responsible for India’s rich and varied biodiversity.
India is one among the top 10 countries with rich biodiversity and one among the 12 Mega biodiversity regions in the world. Around 18 biosphere reserves have been set up in India.
India is home to 350 different mammals (rated highest in the world), 1, 200 species of birds, 453 species of reptiles and 45, 000 plant species. India is home to 50, 000 known species of insects, that include 13, 000 butterflies and moths. It is estimated that the number of unnamed species could be much higher than the existing number.
More than 18 percent of Indian plants are endemic (native to a particular region) to the country and found nowhere else in the world.
India has 27 indigenous breeds of cattle, 40 breeds of sheep, 22 breeds of goats and 8 breeds of buffaloes.
Among the amphibians found in India, 62 percent are unique to this country. High endemism has also been recorded in various flowering plants, insects, marine worms, centipedes, mayflies, and fresh water sponges.
Apart of noticeable diversity in Indian wild plants and animals, there is also a great diversity of cultivated crops and breeds of domestic livestock. The traditional cultivars (a plant variety that has been produced in cultivation by selective breeding) include about 50,000 varieties of rice and a number of cereals, vegetables, and fruits. The highest diversity of cultivars is found concentrated in the high rainfall areas of Western Ghats, Eastern Ghats, Northern Himalayas. and North-Eastern hills.