Thar Desert natural vegetation of this dry area is classed as Northwestern thorn scrub forest occurring in small clumps scattered more or less openly. Density and size of patches increase from west to east following the increase in rainfall. The natural vegetation of the Thar Desert is composed of the following tree, shrub and herb species: The endemic floral species include "Calligonum polygonoides", "Prosopis cineraria", "Acacia nilotica", "Tamarix aphylla", "Cenchrus biflorus". The Thar Desert is the most widely populated desert in the world, with a population density of 83 people per km. In India, the inhabitants comprise Hindus, Muslims, and Sikhs. In
Thar Desert high winds. But the poverty leaves no other option to these jhugiwalas (people living in jhugis). The river Luni is the only natural water source that drains inside a lake in the desert. It originates in the Pushkar valley of the Aravalli Range, near Ajmer and ends in the marshy lands of Rann of Kutch in Gujarat, after travelling a distance of 530 km. The Luni flows through part of Ajmer, Barmer, Jalor, Jodhpur, Nagaur, Pali, and Sirohi districts and Mithavirana Vav Radhanpur region of Banaskantha North Gujarat. Its major tributaries are the Sukri, Mithri, Bandi, Khari, Jawai, Guhiya and