How do gradient and discharge change in a downstream direction and why are glacial valleys shaped differently from river valleys?
Rk Naresh The answer to many questions about river form and behavior can be found in river morphology. The topic is too big for a single answer.
Respected sir
In a downstream direction, the gradient of a river typically decreases as the river flows from its steep, high-energy headwaters to the gentler slopes near its mouth. Consequently, the discharge generally increases downstream as tributaries contribute additional water and the river's drainage area expands.
Glacial valleys are shaped differently from river valleys due to the distinct processes involved in their formation. Glacial valleys are carved by the movement of glaciers, which erode the landscape through plucking and abrasion, resulting in a characteristic U-shape with steep sides and a flat bottom. In contrast, river valleys are primarily shaped by fluvial erosion and sediment transport, leading to a V-shape with a narrow, incised profile and sloping sides.