Geography of India of the world's most intensely farmed areas. The main crops grown are rice and wheat, which are grown in rotation. Other important crops grown in the region include maize, sugarcane and cotton. The Indo-Gangetic plains rank among the world's most densely populated areas. The Thar Desert (also known as "the deserts") is by some calculations the world's seventh largest desert, by some others the tenth. It forms a significant portion of western India and covers an area of . The desert continues into Pakistan as the Cholistan Desert. Most of the Thar Desert is situated in Rajasthan, covering 61% of
Thar Desert or man-made (johads), are often the only source of water for animals and humans in the true desert areas. The lack of a constant water supply causes much of the local population to live as nomads. Most human settlements are found near the two seasonal streams of the Karon-Jhar hills. Potable groundwater is also rare in the Thar desert. Supplies are often sour due to dissolved minerals, and are only available deep underground. Wells that successfully bear sweet water attract nearby settlement, but are difficult to dig, possibly claiming the lives of the well-diggers. According to 1980 housing census in