Biodiversity and Conservation
Biodiversity can be defined as the sum total of diversity that exists at all levels of biological organisation. The three levels of biodiversity are: genetic, species and ecological diversity. The efforts have been made to protect diversity at all these levels.
The kingdom Fungi has more species than all the vertebrate species combined.
The diversity of species diversity on earth is not uniformly distributed instead shows a patterns. The species diversity is generally highest in the tropics and decreases towards the poles.
The species richness is more in the tropics because tropics had more evolutionary time and they provide a relatively constant environment. They receive more solar energy which contributes to greater productivity.
The fossil study reveals the incidence of mass extinctions in the past, but the present rates of extinction, largely attributed to human activities.
The reasons for high extinction rates at present include habitat (particularly forests) loss and fragmentation, over exploitation, biological invasions and co-extinctions.
Species which are under threat of extinction can be classified as: critically endangered species, endangered species and vulnerable species.
India has 8.1% of biodiversity of the world.
The reasons for conserving biodiversity are narrowly utilitarian, broadly utilitarian and ethical. The two strategies for conservation of biodiversity are: in situ conservation and ex situ conservation.
Recently, 34 ‘biodiversity hotspots’ in the world have been proposed for intensive conservation efforts. Of these, three (Western Ghats-Sri Lanka, Himalaya and Indo-Burma) cover India’s rich biodiversity regions.
For in situ conservation in India there are 14 biosphere reserves, 90 national parks and 448 wildlife sanctuaries. Ex situ conservation methods include protective maintenance of threatened species in zoological parks and botanical gardens,
The cryopreservation of gametes of threatened species is also a part for conservation of biodiversity.
Apart from this, a treaty called Convention on Biological Diversity (CBD) has been signed by many nations for conservation of biodiversity.