Biogeographical regions of India

Using the international 'biome' classification system — based on climate, fauna, flora and soil conditions — India is divided into ten distinct biogeographic zones (Fig. 12.3). The Trans-Himalayan Region (5.7% of the country's landmass) is a high-altitude cold desert extending the Tibetan plateau into Ladakh and Lahaul-Spiti, home to the world's richest wild sheep and goat community as well as the Chiru and Black-necked Crane. The Himalayas (7.2%) run the full mountain chain from the north-west to the north-east, hosting wild sheep, mountain goats, shrew, snow leopard and red panda, many of them endangered. The Indian Desert (6.9%), west of the Aravalli range, spans Gujarat's salt desert and Rajasthan's sand desert, and is home to the endemic wild ass alongside the Indian bustard, camel, foxes and snakes. The Semi-Arid Zones (15.6%), between the desert and the Deccan plateau, support nilgai, blackbuck, four-horned antelope, sambar, chital and spotted deer alongside predators like the Asiatic lion, tiger, leopard and jackal. The Western Ghats stretch nearly 1,500 km along the west coast with about 2,000 mm of annual rainfall, sheltering large populations of the Nilgiri tahr (Tamil Nadu's state animal), Nilgiri langur, tiger, leopard and Indian elephant, plus the endemic grizzled squirrel and lion-tailed macaque. The Deccan Peninsula (4.3%) is predominantly deciduous, thorn and semi-evergreen forest holding chital, sambhar, nilgai, elephant, sloth bear, blackbuck and barking deer, and forms the catchment for the Godavari, Tapti, Narmada and Mahanadi rivers. The Gangetic Plains (11%), fertile and shaped by the Ganges river system, support rhinoceros, elephant, buffalo, swamp deer and hog-deer. North-East India (5.2%) forms the biogeographical 'gateway' between the Indian, Indo-Malayan and Indo-Chinese regions and includes the Eastern Himalaya biodiversity hotspot, home to the Indian rhinoceros, leopard and golden langur. The Coastal Region (2.5%) covers sandy beaches, mudflats, coral reefs and mangroves along a roughly 5,423 km coastl …