The removal of soil by running water and wind is known as soil erosion. The soil-forming process and the erosional process of running water and wind are continuous. Gully Erosion: When soil is removed by water flowing along definite paths downs the slope or in channels, it is called gully erosion. Gullies cut up agricultural land andmake it unfit for cultivation. Badland is a region with a large number of deep gulliesor ravines, e.g., Chambal Valley in Madhya Pradesh.