Soil components include sand, silt, clay, gravel, and humus. Each soil component has unique properties. The water cycle includes the processes of evaporation, condensation, and precipitation and the passage of water over and through land. These processes affect the shape of the land. Both the flow of water and the slope of the land affect erosion and deposition.
Tributaries are branches of streams that converge to form the trunk of a larger stream, or river.
Together, they act as a system that drains the land. Land forms, such as canyons and deltas, result from the action of flowing water. Humans can affect erosion and deposition in various ways, including clearing the land, planting vegetation, and building dams. Hills, rocks, plants, and dams may change the direction and flow of water. Aerial photographs are views of land or other surfaces as seen from above.