Western Ghats

The Western Ghats or Sahyadri mountains run along the western edge of India's Deccan Plateau, and separate the plateau from a narrow coastal plain along the Arabian Sea. The range starts south of the Tapti River near the border of Gujarat and Maharashtra, and runs approximately 1600 km through the states of Maharashtra, Goa, Karnataka, Kerala, and Tamil Nadu, almost to the southern tip of the Indian peninsula. The average elevation is around 900 meters. Higher peaks occur in the northern section of the range in Maharashtra, notably Kalsubai 1646 m (5427 ft), Mahabaleshwar 1438 m (4710 ft) and Harishchandragarh 1424 m (4691 ft); in southwest Karnataka, notably Kudremukh at 1862 m; and in the southern part of the range, with Anai Mudi in Kerala at 2695 meters height the highest peak in the Western Ghats. The only major gap in the range, the Palghat Gap, joins Tamil Nadu to Kerala. Smaller ranges, including the Nilgiri Hills of northwestern Tamil Nadu and Biligirirangans southeast of Mysore in Karnataka, meet the Shevaroys (Servarayan range) and Tirumala range farther east, linking the Western Ghats to the Eastern Ghats. These ranges of hills serve as important wildlife corridors, allowing species like elephants to move between the ranges.

The northern portion of the narrow coastal plain between the Western Ghats and the Arabian Sea is known as the Konkan Coast or simply Konkan, and the southern portion is called Malabar or the Malabar Coast. The foothill region east of the Ghats in Maharashtra is known as Desh, while the eastern foothills of central Karnataka state is known as Malnad region. The largest city within the mountains is the city of Pune, in the Desh region on the eastern edge of the range.

The mountains intercept the rain-bearing westerly monsoon winds, which cool as they are pushed upwards by the mountain slopes and release their moisture as rain. The dense forests also contribute to the precipitation of the area by acting as a substrate for condensation of moist rising (orographic) winds from the sea, and releasing much of the moisture back into the air via transpiration, allowing it to later condense and fall again as rain. The westward-facing slopes receive much more rain than the eastward-facing slopes, and the Western Ghats are considerably wetter than the dry Deccan to the east. The Western Ghats form the most important watershed for peninsular India, the plentiful rain giving rise to numerous streams, with many waterfalls, which form the headwaters of both the short rivers that run to the Arabian Sea and the great perennial rivers of the Deccan, including the Godavari River, Krishna River, Cauvery River and their tributaries, which empty into the Bay of Bengal. Many of these rivers and streams are threatened by pollution from mining, agricultural and urban runoff, coffee pulp effluents and other human activity. There has recently been a strong movement to curb mining operations in the Western Ghats, as this is one of the global Biodiversity hotspots. One standing example of such a campaign is the one in Kudremukh, where Iron ore is mined, and the river Kali is used to transport ore.

Historically the Western Ghats were well-covered in dense forests. In the south they contain the only rainforests of southern India. These forests are home to an interesting and diverse fauna and flora, many of them showing affinities to Southeast Asia, but are increasingly threatened by human activity. Several national parks and other protected areas lie within the range, but it is estimated that only a small fraction of the Western Ghats remains in pristine condition. The Silent Valley National Park in Kerala is considered by many to be the last tracts of virgin tropical evergreen forest in India.

Biogeographers have long recognized the distinctive plant and animal communities of the Western Ghats. Many of these faunal and floral elements are not found anywhere else in the India except in parts of northeastern India. The Western Ghats are also home to many endemic species, and the endemism is especially high in the amphibian and reptilian fauna. The snake family Uropeltidae is almost entirely restricted to and diversified in this region of the world. The frog Nasikabatrachus sahyadrensis was discovered in 2003 as being a living fossil.

The Western Ghats are ecologically distinct from the drier regions to the north and east, but can be further divided into four ecoregions. The northern portion of the range is generally drier than the southern portion, and at lower elevations makes up the North Western Ghats moist deciduous forests ecoregion, with mostly deciduous forests made up predominantly of teak (Tectona grandis) and dipterocarps. Above 1000 meters elevation are the cooler and wetter North Western Ghats montane rain forests, whose evergreen forests are characterized by trees of family Lauraceae.

The evergreen Wayanad forests of Kerala and Tamil Nadu mark the transition zone between the northern and southern ecoregions of the Western Ghats. The southern ecoregions are generally wetter and more species-rich. At lower elevations are the South Western Ghats moist deciduous forests, with Cullenia is the characteristic tree genus, accompanied by teak, dipterocarps, and other trees. These moist forests transition to the drier South Deccan Plateau dry deciduous forests to the east, in the mountains' rain shadow. Above 1000 meters are the South Western Ghats montane rain forests, also cooler and wetter than the surrounding lowland forests, and dominated by evergreen trees, although some montane grasslands and stunted forests can be found at the highest elevations. The South Western Ghats montane rain forests are the most species-rich ecoregion in peninsular India; eighty percent of the flowering plant species of the entire Western Ghats range are found in this ecoregion. It also harbors the highest levels of endemism: 35 percent of the plants, 42 percent of the fishes, 48 percent of the reptiles, and 75 percent of the amphibians that live in this ecoregion are endemic. Still higher, above elevations of 1600 MSL are seen the shola-grassland mosaic, which are habitats exclusive to the Western Ghats.de:Westghats kn:ಸಹ್ಯಾದ್ರಿ ja:西ガーツ山脈 uk:Ґати Західні