1. Erosion: This involves the wearing away and transportation of rock and soil by the flowing water.

* Hydraulic Action: The force of the water itself can dislodge and move rocks and soil. This is especially powerful during floods.

* Abrasion: Rocks and sediment carried by the river act like sandpaper, grinding and wearing away the riverbed and banks.

* Corrosion: The slightly acidic water can dissolve certain types of rock, especially limestone.

2. Deposition: This involves the dropping or settling of eroded material as the river's energy decreases.

* Sediment Transport: Rivers carry a wide range of sediment sizes, from fine clay to large boulders. The speed and volume of the water determine what size sediment can be carried.

* Decreased Energy: When a river slows down, its energy decreases. This causes it to drop the heavier sediment first, with finer material being deposited further downstream.

* Landforms: The deposition of sediment creates a variety of landforms, including:

* Floodplains: Wide, flat areas along the river that are prone to flooding.

* Meanders: Curving bends in the river, created by erosion on the outside of the bend and deposition on the inside.

* Oxbow Lakes: Crescent-shaped lakes formed when a meander is cut off from the main river channel.

* Deltas: Fan-shaped deposits at the mouth of a river where it enters a lake or ocean.

Overall, the interplay between erosion and deposition leads to constant changes in the landscape, shaping river valleys, valleys, floodplains, and other features. This dynamic process is a fundamental aspect of Earth's constantly evolving surface.