- Discharge increases, as noted above, because water is added to the stream from tributary streams and groundwater.
- As discharge increases, the width, depth, and average velocity of the stream increase.
- The gradient of the stream, however, will decrease.
How does the gradient of a river change from headwaters to mouth?
Stream gradients tend to be higher in a stream’s headwaters (where it originates) and lower at their mouth, where they discharge into another body of water (such as the ocean). ... Discharge increases downstream in most rivers, as tributaries join the main channel and add water.
How does a stream’s gradient typically change as you move from the head of the stream toward the mouth?
Stream gradient tends to decrease as you move from the headwaters (source area) of a stream toward its mouth (where a steam enters a body of water such as a lake or ocean). Stream roughness tends to decrease as you move toward the mouth because larger rocks are not easily transported by the stream.
What happens to the gradient of streams as they increase in order?
As the order of the stream increases, the discharge increases , the gradient decreases, the velocity increases, and the channel dimensions (width and depth) increase to accommodate the increased discharge.
How does a stream’s gradient affect its velocity?
Gradient looks at how far the water drops over the distance the water actually flows . The gradient influences the velocity of the stream. The steeper the gradient, the higher will be the velocity if all other factors are held constant.
What is the relationship between gradient and stream load?
As the velocity rises or falls , so does the amount of load. Consider the situation of where a stream flows into a body of water. As the stream flows downslope, it is carrying a load based on the gradient and velocity of the stream. When the stream empties into the water body, that gradient is lost.
What is the ultimate base level for stream erosion?
Sea level is referred to as the ultimate base level, because all streams, rivers and waterways eventually erode toward that ultimate destination.
What factors control a stream’s velocity?
The velocity of a river is determined by many factors, including the shape of its channel, the gradient of the slope that the river moves along , the volume of water that the river carries and the amount of friction caused by rough edges within the riverbed.
What happens to a river as its load discharge and gradient decrease?
As one moves along a stream in the downstream direction: Discharge increases, as noted above, because water is added to the stream from tributary streams and groundwater. As discharge increases, the width, depth, and average velocity of the stream increase. The gradient of the stream, however, will decrease .
How would an increase in gradient affect the speed of water?
If the slope is too gentle and velocity is too slow to transport the sediments being supplied by weathering and erosion, the sediments will pile up . This increases the gradient which causes the water to flow faster which increases erosion and transport, which then reduces the gradient.
What affects stream gradient?
A stream that flows upon a uniformly erodible substrate will tend to have a steep gradient near its source, and a low gradient nearing zero as it reaches its base level. ... Human dams, glaciation, changes in sea level , and many other factors can also change the “normal” or natural gradient pattern.
How do gradient and discharge change between a stream’s headwaters and its mouth?
How do gradient and discharge change between a stream’s headwaters and its mouth? While gradient decreases between a stream’s headwaters and mouth, discharge increases . ... A stream profile is a cross-section view of a stream from its headwaters to its mouth.
Why is stream gradient important?
Why is stream gradient important? The gradient, or steepness, of a streambed drives many important processes, such as erosion , sediment movement, and the speed of water flow. ... Artificially flat channels may result in slow moving water and excessive sediment deposits, which can contribute to flooding.
How does gradient affect erosion?
Slope gradient greatly affects amount of surface water run-off and soil sediment loss . Soil erosion rates becomes acute when slope angle exceeds a critical value and then increases logarithmically. The slope gradient can have variable effect in different climatic zones, depending mainly on annual rainfall.
How do we calculate gradient?
To calculate the gradient of a straight line we choose two points on the line itself. The difference in height (y co-ordinates) ÷ The difference in width (x co-ordinates) . If the answer is a positive value then the line is uphill in direction. If the answer is a negative value then the line is downhill in direction.
