| Himalayan biodiversity | | | Dr. Parveen Kumar, Dr. R. K. Arora, Dr. Pawan Kumar | 9/25/2018 10:36:11 PM |
| The Himalayas are considered as the young folded mountains being recognized worldwide for a highly rich diverse flora and fauna. Besides sustaining high levels of biodiversity and human wellbeing these are also acknowledged widely for regulating hydrological integrity. A publication from the Zoological Survey of India reports that the Indian Himalayas, which constitute about 12% of the country's landmass, is home to about 30.16% of its fauna. The publication 'Faunal Diversity of Indian Himalaya', lists 30,377 species/subspecies in the region with the entire identified fauna in the country adding up to 1, 00,762. Spread across six States from Jammu and Kashmir in the west through Himachal Pradesh, Uttarakhand, Sikkim and West Bengal's Darjeeling to Arunachal Pradesh in the far east, the Indian Himalayas are divided into two bio-geographic zones viz the Trans-Himalaya and the Himalaya. The entire region, spread over 3.95 lakh sq. km., is home to 280 species of mammals, 940 species of birds, 316 species of fishes, 200 species of reptiles and 80 species of amphibians. This put together accounts for 27.6% of the total vertebrate diversity of the country. The Himalayas are generally divided into Western Himalayas and Eastern Himalayas. Western Himalayas are above 36°N Lat. (Mt. Godwin-Austin), and eastern Himalayas are below 28°N Lat. (Kanchenjunga). Thus the 8° difference in the latitude between the two ends of the Himalayas has affected the altitude of the regional snowline so that it is lower in western Himalayas and higher in the east. The difference in the observed level of the snowline in western and eastern Himalayas is also due to yearly changes in the climatic conditions of the region. The western Himalayas cover the state of Jammu and Kashmir, Punjab, Himachal Pradesh, Haryana, Uttar Pradesh and the Eastern Himalayas cover the states of Sikkim, Arunachal Pradesh, Assam, Meghalaya, Nagaland, Mizoram, Manipur and Tripura. This accounts for 52.03 percent of the eastern Himalayan region. This Eastern Himalayan region having diverse climatic condition and complex topography comprises of different types of forest and vegetations. The vegetation types in the Eastern Himalayas comprise of (a) Tropical, (b) Sub-tropical, (c) Warm temperate, (d) Cool temperate, (e) Sub-alpine and (f) Alpine. The Eastern Himalayan region home to a remarkable number of globally significant mammals (45 species); birds (50 species); reptiles (16 species); amphibians (12 species); invertebrates (2 species) and plants (36 species), and majority of these species (about 144 species) are found particularly in the northeastern states of India (CEPF 2005). Besides supporting one of the world's richest alpine floras, about one-third of the total flora is endemic to the Eastern Himalayan region.
The Indian Himalayas also have 131 protected areas (PAs), which cover 9.6% of the entire protected area of the country, almost the same as the Western Ghats (10% of protected areas), another biodiversity hotspot in the country. The protected areas include 20 national parks, 71 wildlife sanctuaries, five tiger reserves, four biosphere reserves and seven Ramsar Wetland sites. Of the 940 bird species found in the Indian Himalayas, 39 are endemic to the region. The Indian Himalayas host 1,249 species/subspecies of butterflies, with the highest density recorded in Arunachal Pradesh. Some of the rare high-altitude butterflies found in the Himalayas are Parnassius stoliczkanus (Ladakh banded Apollo) and Parnassius epaphus (Red Apollo), listed under Schedule I and Schedule II of the Wildlife Protection Act. Similarly The Hindu Kush Himalayas (HKS) the extended part of the western Himalayas covering the countries of Afghanistan, Bangladesh, Bhutan, China, India, Myanmar, Nepal and Pakistan also hosts parts of the four Global Biodiversity Hotspots; namely, the Himalayas Hotspot, the Indo-Burma Hotspot, the Mountains of South-West China Hotspot, and the Mountains of Central Asia Hotspot. The region, with its varied landscapes and soil formation, and variety of vegetation types and climatic conditions, is well known for its unique flora and fauna, and has a high level of endemism and numerous critical eco regions of global importance. Approximately 39% of the HKH is comprised of grassland, 20% forest, 15% shrub land, and 5% agricultural land. The remaining 21% is made up of other types of land use such as barren land, rock outcrops, built-up areas, snow cover, and water bodies.
The survival of the Himalayan ecosystems and biodiversity are now threatened by various human activities like timber harvesting, intensive grazing by livestock and agricultural expansion into forest lands, and above all the climate change. These are ultimately the problems arising out of the so called 'modernization' of the society. The emission of green house gases emission, conversion of agricultural land for commercial purposes; deforestation and land degradation have already shown their consequences. The Climate change has emerged as one of the major threats resulting in biodiversity loss in the Himalayan region. In view of the prevailing trend, the consequences of biodiversity loss from climate change are likely to be greatest on the poor and marginalized people who depend almost exclusively on the natural resources. Grabherr et al. (1994) estimated that a 0.50 degrees rise in temperature per 100 m elevation could lead to a theoretical shift in altitudinal vegetation belts at the rate of 8-10 m per decade. This altitudinal shift in the Eastern Himalayan region is expected to be around 80m-200m per decade given the current trend in the region estimated at around 0.040C-0.10C/yr with greater shifts at the higher altitudes since the rate of warming increases with altitude. Besides this about 133 vertebrate species of the region are cited as threatened in the IUCN Red List. This includes 43 species of mammals like the critically endangered Pygmy Hog, the Namdapha flying squirrel and the endangered Snow leopard, the Red Panda and the Kashmir Gray Langur. Fifty-two species of birds are also in the threatened category like the critically endangered White-Bellied Heron and Siberian crane and vulnerable species like the Black Necked crane and the Indian Spotted eagle, among others. |
|
