When the gradient of a river channel changes from a steep to a gentle angle, the main activity of the river will be

When the gradient of a river channel changes from steep to gentle, the main activity of the river will be depositing. This means that the river will drop and deposit the sediments it has been carrying, such as sand, mud, and rocks, on the riverbed and along the banks. As the river slows down due to the decrease in gradient, it loses the energy required to transport the sediments, resulting in deposition. Deposition creates new landforms, such as sandbars and floodplains, which can support vegetation and wildlife habitats. Therefore, a decrease in gradient can lead to positive ecological effects.