Biodiversity is the variability among living and non-living organisms and ecological complexes of which they are part, including diversity within and between species and ecosystems. Biodiversity has direct consumptive value in food, agriculture, medicine and industry. In the opinion of experts, the more diverse the species population (both in number of species and quantity of each species), the more risk is spread over the entire community, because several food sources exist at each trophic level. In other words, greater diversity in ecosystem results in greater stability.
India has been divided into ten Bio-geographic zones and these zones together consist of 25 bio-geographic provinces. The aim is to designate one representative site as Biosphere Reserve in each bio-geographic zones for long term conservation.
The Bio-geographic zones of India area:
Biosphere Reserves (BRs) are internationally designated landscape/seascape units under UNESCO’s flagship programme-‘Man and Biosphere (MAB)’. The Biosphere Reserves represent characteristic ecosystems in different bio-geographic regions and consider human communities as their integral component.
The objectives of Biosphere Reserves include:
(i) ensuring in-situ conservation (at all levels of biodiversity ranging from genes to ecosystem);
(ii) widening the understanding (through research and monitoring) of components of ecosystems; (iii) achieving integrated development (improved quality of life for indigenous communities living in and around) of the area.
The Biosphere Reserves are, therefore, sites for experimenting with and learning about sustainable development.
Considering the importance of such areas, a total of 580 units in 114 countries have been designated in the World Network of Biosphere Reserves (WNBR). Out of the 18 Biosphere Reserves designated nationally, 9 Biosphere Reserves have been admitted to the World Network so far.
Biosphere Reserves of India on the World Network of Biosphere Reserves
| S. No. | Name | States | Year in which added |
| to World Network | |||
| 1 | Nilgiri Biosphere Reserve | Tamil Nadu, Kerala, Karnataka | 2000 |
| 2 | Gulf of Mannar Biosphere Reserve | Tamil Nadu | 2001 |
| 3 | Sundarbans Biosphere Reserve | West Bengal | 2001 |
| 4 | Nanda Devi Biosphere Reserve | Uttarakhand | 2004 |
| 5 | Nokrek Biosphere Reserve | Meghalaya | 2009 |
| 6 | Panchmarhi Biosphere Reserve | Madhya Pradesh | 2009 |
| 7 | Simlipal Biosphere Reserve | Odisha | 2009 |
| 8 | Achanakmar-Amarkantak Biosphere Reserve | Madhya Pradesh, Chhathisgarh | 2012 |
| 9 | Great Nicobar | Andaman and Nicobar | 2013 |
The Biosphere Reserves Programme was initiated in India in 1986 and till date, 18 sites have been designated as Biosphere Reserves (BR) in different parts of the country.