Thursday, January 26, 2017

Biodiversity Hot Spots (Environment Notes)


  • Hot spots are the richest and most threatened reservoirs of plant and animal life of the earth. They have maximum number of endemic species.
  • 25 terrestrial hot spots have been identified for the conservation of biodiversity. They occupy 1.4% of the earth’s surface and 20% of worlds the human population lives in these areas. Western Ghats and Eastern Himalayas (Includes some parts of Indo-Burma or Purvanchal Hills) are two hot spots of India.
To qualify as a hot spot, a region must meet two strict criteria:
  1. Species endemism: the region must contain at least 1,500 species of vascular plants (> 0.5% of the world’s total) as endemics, and
  2. Degree of threat: the region has to have lost at least 70% of its original habitat.
  • Each biodiversity hot spot represents a remarkable universe of extraordinary floral and faunal endemism struggling to survive in rapidly shrinking ecosystems.
  • Over 50 percent of the world’s plant species and 42 percent of all terrestrial vertebrate species are endemic to the 34 biodiversity hot spots.
  • Some hot spots are much richer than others in terms of their numbers of endemics. Five key factors have been taken into consideration and those biodiversity hot spot that tops the list with respect to these five factors are considered as hottest hot spots.

Factors

  1. Endemic plants,
  2. Endemic vertebrates,
  3. Endemic plants/area ratio (species per 100km2),
  4. Endemic vertebrates/area ratio (species per 100km2) and
  5. Remaining primary vegetation as % of original extent.

Biodiversity Hotspots Across the World

The eight hottest hot spots in terms of the above five factors are:
  1. Madagascar
  2. Philippines
  3. Sundaland [South East Asia]
  4. Brazil’s Atlantic Forest
  5. Caribbean
  6. Indo-Burma
  7. Western Ghats and Sri Lanka
  8. Eastern Arc and Coastal Forests of Tanzania/Kenya
These eight ‘hottest hot spots’, appear at least three times in the top ten listings for each factor.
Biodiversity Hotspots Across the World

Indian Biodiversity Hot Spots

There are 3 biodiversity hot spots present in India. They are:
  1. The Eastern Himalayas [Arunachal Pradesh, Bhutan, Eastern Nepal]
  2. Indo-Burma and [Purvanchal Hills, Arakan Yoma, Eastern Bangladesh]
  3. The Western Ghats and Sri Lanka

Indo-Burma Region

  • The Indo-Burma region encompasses several countries.
  • It is spread out from Eastern Bangladesh to Malaysia and includes North-Eastern India south of Brahmaputra river, Myanmar, the southern part of China’s Yunnan province, Lao People’s Democratic Republic, Cambodia, Vietnam and Thailand.
  • The Indo-Burma region is spread over 2 million sq. km of tropical Asia.
  • Since this hotspot is spread over such a large area and across several major landforms, there is a wide diversity of climate and habitat patterns in this region.

Biodiversity of Indo-Burma Region

  • Much of this region has been deteriorating rapidly in the past few decades.
  • This region is home to several primate species such as monkeys, langurs and gibbons with populations numbering only in the hundreds.
  • Many of the species, especially some freshwater turtle species, are endemic.
  • Almost 1,300 bird species exist in this region including the threatened white-eared night-heron [Endangered], the grey-crowned crocias [Endangered], and the orange-necked partridge [Near Threatened].
  • It is estimated that there are about 13,500 plant species in this hotspot, with over half of them endemic. Ginger, for example, is native to this region.

The Eastern Himalayas

  • The Eastern Himalayas is the region encompassing Bhutan, northeastern India, and southern, central, and eastern Nepal.
  • The abrupt rise of the Himalayan Mountains from less than 500 meters to more than 8,000 meters results in a diversity of ecosystems that range from alluvial grasslands and subtropical broad leaf forests along the foothills to temperate broad leaf forests in the mid hills, mixed conifer and conifer forests in the higher hills, and alpine meadows above the tree line.

Biodiversity of the Eastern Himalayas

  • The Eastern Himalayan hotspot has nearly 163 globally threatened species (both flora and fauna) including the One-horned Rhinoceros [Vulnerable], the Wild Asian Water buffalo [Endangered].
  • There are an estimated 10,000 species of plants in the Himalayas, of which one-third are endemic and found nowhere else in the world.
  • A few threatened endemic bird species such as the Himalayan Quail, Cheer pheasant, Western tragopan are found here, along with some of Asia’s largest and most endangered birds such as the Himalayan vulture and White-bellied heron.
  • Mammals like the Golden langur, The Himalayan tahr, the pygmy hog, Lang-urs, Asiatic wild dogs, sloth bears, Gaurs, Muntjac, Sambar, Snow leopard, Black bear, Blue sheep, Takin, the Gangetic dolphin, wild water buffalo, swamp deer call the Himalayan ranged their home.

Western Ghats and Sri Lanka

  • Western Ghats, also known as the “Sahyadri Hills” encompasses the mountain forests in the southwestern parts of India and highlands of southwestern Sri Lanka.
  • The entire extent of hotspot was originally about 1,82,500 square kms, but due to tremendous population pressure, now only 12,445 square Km or 6.8% is in pristine condition.
  • The wide variation of rainfall patterns in the Western Ghats, coupled with the region’s complex geography, produces a great variety of vegetation types.
  • These include scrub forests in the low-lying rainshadow areas and the plains, deciduous and tropical rainforests up to about 1,500 meters, and a unique mosaic of montane forests and rolling grasslands above 1,500 meters.
  • In Sri Lanka diversity includes dry evergreen forests to dipterocarpus dominated rainforests to tropical montane cloud forest.
  • The important populations include Asian elephant, Niligiri tahr, Indian tigers, lion tailed macaque [All Endangered], Indian Giant squirrel [Least Concern], etc.

World Heritage Sites

  • World Heritage Sites means “Sites any of various areas or objects inscribed on the United Nations Educational, Scientific, and Cultural Organization (UNESCO) World Heritage List”.
  • The sites are designated as having outstanding universal value under the Convention concerning the Protection of the World Cultural and Natural Heritage.
  • This Convention, which was adopted by the UNESCO in 1972 (and enforced in 1975) provides a framework for international cooperation in preserving and protecting cultural treasures and natural areas throughout the world. The first list of World Heritage state was published in 1978.
  • The convention defines the kind of sites which can be considered for inscription of the World heritage list (ancient monuments, museums, biodiversity and geological heritage,), and sets out the duties of the State Parties in identifying potential sites and their role in protecting them.
“Natural heritage sites are restricted to those natural areas that
  • furnish outstanding examples of the Earth’s record of life or its geologic processes.
  • provide excellent examples of ongoing ecological and biological evolutionary processes.
  • contain natural phenomena that are rare, unique, superlative, or of outstanding beauty
or
  • furnish habitats or rare endangered animals or plants or are sites of exceptional biodiversity”.
  • There are ten criteria for cultural heritage and natural heritage.
  • Nominated sites must be of “outstanding universal value” and meet at least one of the ten criteria. The criteria are given below.

Criteria

  1. to represent a masterpiece of human creative genius;
  2. to exhibit an important interchange of human values, over a span of time or within a cultural area of the world;
  3. to bear a unique or at least exceptional testimony to a cultural tradition or to a civilization which is living or which has disappeared;
  4. to be an outstanding example of a type of building, architectural or technological ensemble or landscape which illustrates a significant stage(s) in human history;
  5. to be an outstanding example of a traditional human settlement, land-use, or sea-use,;
  6. to contain superlative natural phenomena or areas of exceptional natural beauty and aesthetic importance;
  7. to be outstanding examples representing major stages of Earth’s history;
  8. to contain the most important and significant natural habitats for insists conservation of biological diversity, including those containing threatened species of outstanding universal value from the point of view of science or conservation.
  • The UNESCO funds numerous efforts to preserve and restore World Heritage Sites in developing nations.
  • It maintains also a List of World Heritage Sites in developing nations.
  • It maintains also a List of World Heritage in danger facing threat of pollution and other natural hazards.
  • Sites subject to unusual levels of pollution, natural hazards, or other problems may be placed for restoration. Such designated sites facilitate promotion of tourism.

International Year of Biodiversity

  • The United Nations declared 2010 to be the International Year of Biodiversity. It is a celebration of life on earth and of the value of biodiversity for our lives.
Slogan
“Biodiversity is variety of life on earth
Biodiversity is life.
Biodiversity is our life”.

No comments: