Describe the main forms of river erosion.

Erosion is the wearing away of the bank of the river as well as the bedload it transports. There are four main forms of river erosion. Firstly, Hydraulic action is where the force of the water acts to break rock particles away from the river channel. Abrasion is where the bedload (rocks in transport) wear away the river's banks. Thridly, attrition is the collision of bedload to erode itself. Finally, Solution is where the river water dissolves rock particles and occures to both the bedload and the river bank. The dominance of each type of erosion will vary across both time and space.