How does erosion from runoff differ from stream erosion?

How does erosion from runoff differ from stream erosion?

As the runoff flows, it may pick up loose bits of soil and sand. Runoff causes more erosion if the land is bare. Much of the material eroded by runoff is carried into bodies of water, such as streams, rivers, ponds, lakes, or oceans. Runoff is an important cause of erosion.

How does a stream erode?

Hydraulic action, abrasion, and solution are the three main ways that streams erode the earth’s surface. Hydraulic action. The ability of flowing water to dislodge and transport rock particles or sediment is called hydraulic action.

What happens to a river as it hits flatter land and flows more slowly?

The slope of the land over which the water flows is one factor. Flowing water eventually slows down and deposits the sediments it is carrying. It may slow down when it reaches flatter land. Or it may slow down when it flows into a large body of still water, such as a lake or the ocean.

What happens to rivers and streams as they continue to flow down a mountain to flatter ground?

As the river moves onto flatter ground, the stream erodes the outer edges of its banks to carve a floodplain, which is a flat level area surrounding the stream channel (figure 26). Streams work to down cut in their stream beds until they reach base level.

What is the difference between stream velocity and stream discharge?

Stream velocity is the speed of the water in the stream. Units are distance per time (e.g., meters per second or feet per second). Stream discharge is the quantity (volume) of water passing by a given point in a certain amount of time.

What is the difference between a stream and a river?

A river is a natural flow of running water that follows a well-defined, permanent path, usually within a valley. A stream (also called a brook or a creek) is a natural flow of water that follows a more temporary path that is usually not in a valley.

How is the mountain stream different from the water fall?

A mountain stream flows very quickly because of the steep slope. The rapidly falling water digs down into the stream bed and makes it deeper. The slope is so steep that water cascades down in a waterfall.

What are the effects of floods on the stream compared to average flows on erosion and moving sediment?

Flood Erosion and Deposition: As flood waters rise, the slope of the stream as it flows to its base level (e.g., the ocean or a lake) increases. Also, as stream depth increases, the hydraulic radius increases thereby making the stream more free flowing. Both of these factors lead to an increase in stream velocity.

When a stream has a greater supply of sediment than it can carry?

Aggradation (or alluviation) is the term used in geology for the increase in land elevation, typically in a river system, due to the deposition of sediment. Aggradation occurs in areas in which the supply of sediment is greater than the amount of material that the system is able to transport.

What is river and stream erosion?

Lesson Summary. Rivers and streams erode the land as they move from higher elevations to the sea. Eroded materials can be carried in a river as dissolved load, suspended load, or bed load. A river will deeply erode the land when it is far from its base level, the elevation where it enters standing water like the ocean.

How does the elevation of a stream affect erosion?

The higher the elevation, the farther the stream is from where it will reach base level and the more cutting it has to do. As a stream gets closer to base level, its gradient lowers and it deposits more material than it erodes.

What happens to a stream as it moves out of the mountains?

As a stream moves out of high mountainous areas into lower areas closer to sea level, the stream is closer to its base level and does more work eroding the edges of its banks than downcutting into its stream bed. At some point in most streams, there are curves or bends in the stream channel called meanders (Figure 10.3).

Why does a stream deposit more material than it erodes?

As a stream gets closer to base level, its gradient lowers and it deposits more material than it erodes. On flatter ground, streams deposit material on the inside of meanders. A stream’s floodplain is much broader and shallower than the stream’s channel.

Where does erosion take place in a river?

A river erodes deeply when it is far from its base level, the place where it enters standing water. Streams form bends, called meanders. Broad, flat areas are known as floodplains. A delta or an alluvial fan might form where the stream drops its sediment load.