**2. Extent of ravine in India**

In India the ravines have mostly developed along the river systems having highly productive and deep alluvial soils. The National Commission on Agriculture estimated 3.67 M ha of ravine lands 1.12% of total geographical area of India [6]. Out of 3.67 M ha of ravine lands in India, 2.36 M ha (64%) exists in Uttar Pradesh, Madhya Pradesh, Bihar, Rajasthan, and Gujarat states of India [7]. The ravines on *Yamuna* and *Chambal* River are the largest and most severely degraded ecosystems in the country. Besides these the ravines also extends from the banks of the *Tapti*, *Narmada*, *Watrak*, *Sabarmati*, and *Mahi* River. However, some staggered patches of ravines are also found in *Chota Nagpur* plateau, *Mahanadi* river basin and upper *Sone* Valley, *Indo-Gangetic* plains, *Shiwaliks* and *Bhabar* tract, and Western Himalayas even up to the *Kashmir* Valley [7]. In unmanaged conditions rate of ravine extension ranges from 0.6 to 1.0 m per year and is much greater on sandy soil than on the clay loam soils. The average annual loss of nutrients from these ravine lands due to soil erosion has been estimated at 5.37–8.4 Mg resulting into loss of production due to non-reclamation of ravines [8].
