Context

• Biodiversity Hotspots areas that have extremely rich and diverse flora and fauna and are under threat of getting endangered. Officially, four Biodiversity hotspots of India out of the 36 Biodiversity Hotspots in the world are present.

• They are:

  • the Himalayas,

  • the Western Ghats,

  • the Indo-Burma region and

  • the Sundaland.

• To these may be added the Sundarbans and the Terrai-Duar Savannah grasslands for their unique foliage and animal species. 

About Biodiversity hotspots of India

Himalayas

• Broad-leaved trees giving way to evergreen forests of oak and conifers to alpine meadows at much higher elevations where trees can’t grow because of the harsh climate and only ground-hugging plants thrive.
• Innumerable animal species-charismatic western tragopan & snow leopard whose favourite prey is the bharal and ibex.

Indo-Burma region

• One of the largest hotspots, covers Myanmar, Thailand, Cambodia, Vietnam, Laos PDR and also includes the Gangetic plains, areas around the Brahmaputra river and parts of Andaman and Nicobar Islands.
• Fed with rich alluvial soil by several large Asian rivers besides the Ganga and Brahmaputra
• Species found here like the Annamite muntjac and grey-crowned crocias.

Western Ghats

• World Heritage Site,
• In the southern forests live the arboreal and shy lion-tailed macaques
• Weird pig-nosed purple frog (More details on WG has been updated earlier)

Sundaland

• Part of India that falls in the Sundaland Hotspot is the Nicobar Islands.
• Extends to the tectonic plates under the Indian Ocean.
• Home to iconic species like orangutans, pig-tailed langurs, Javan and Sumatran rhinos, and proboscis monkeys found only in Borneo
• Home to the world’s largest flowers, the rafflesia, which measure one metre across.

Terrai-duar Savannah

• The world’s tallest and rarest grasslands are found in the Terrai-duar Savannah region, which form a narrow stretch at the base of the Himalayas — a continuation of the Indo-Gangetic plain in India, Nepal and Bhutan.
• These grasslands are fed by the rich silt deposited by the monsoon floods every year.
• The elephant grass is home to the one-horned rhinoceros that appears to be like a grey boulder in the tall grass,
• Asian elephants and sloth bears, among other animals.

Sunderbans

• A set of 104 islands formed by the Ganga-Brahmaputra delta, comprises the largest mangrove forest in the world.
• In this World Heritage Site, the Royal Bengal tigers swim in the creeks, the Gangetic dolphins play in the rivulets, while the estuarine crocodiles bask on the river-banks.
• The rising sea, owing to global warming, poses a grave danger of drowning these bountiful islands.

Back to Basics

About biodiversity hotspot 

• The British biologist Norman Myers coined the term “biodiversity hotspot” in 1988 as a biogeographic region characterized both by exceptional levels of plant endemism and by serious levels of habitat loss. In 1990 Myers added a further eight hotspots, including four Mediterranean-type ecosystems. 
• Conservation International (CI) adopted Myers’ hotspots as its institutional blueprint in 1989, and in 1996, the organization made the decision to undertake a reassessment of the hotspots concept. 
• To qualify as a biodiversity hotspot on Myers 2000 edition of the hotspot-map, a region must meet two strict criteria:
  • it must contain at least 0.5% or 1,500 species of vascular plants as endemics, and
  • it has to have lost at least 75% of its primary vegetation.
• These sites support nearly 60% of the world’s plant, bird, mammal, reptile, and amphibian species, with a very high share of those species as endemics.
• Some of these hotspots support up to 15,000 endemic plant species and some have lost up to 95% of their natural habitat.
• Biodiversity hotspots host their diverse ecosystems on just 2.4% of the planet’s surface, however, the area defined as hotspots covers a much larger proportion of the land.
• Overall, the current hotspots cover more than 15.7% of the land surface area, but have lost around 85% of their habitat.

Source: TH

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