How does the long profile of a river change from source to mouth?
The long profile of a river shows changes in the height (altitude) of the course of a river from its source to its mouth. A long profile is usually concave and the slope becomes more gentle towards the mouth of the river. Long profiles usually have irregularities such as waterfalls or lakes.
What is the gradient of a river from its source to its mouth?
Long profile. This is the change in altitude and gradient from the source to the mouth of a river. Essentially, a river erodes its way down through the landscape (vertical erosion) until it reaches base level (usually the sea but sometimes an inland lake).
How is a river formed headwater and mouth?
Rivers collect and carry fresh water from a high point like a hill or a mountain. The beginning point of a creek or stream is called its headwater. Rivers move downstream from the headwater (highest point) to the mouth (or lowest point). Upstream means against the current or flow back up the river to the headwater.
What is a stream’s gradient and how does it change from the headwaters to the 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).
How does gradient change discharge?
How do gradient and discharge change between a stream’s headwaters and its mouth? While gradient decreases b/w a stream’s headwaters and mouth, discharge increases. Gradient and discharge determine the velocity.
Which load is responsible for the most stream erosion?
Most of the sediment in a stream is carried as suspended load. It does not contribute greatly to stream erosion, since it is not in frictional contact with the stream bed. Bed load. The heavier, coarser‐grained earth material that travels along the bottom of the stream is the bed load.
What are the 3 types of stream load?
Stream load is broken into three types: dissolved load, suspended load, and bed load (Ritter, 2006).
Which stream environment has the highest competence?
During summer the glacier melts and adds more water to the river, Also the head water regions of braided stream are located at the river source and at this point the slope is very high and this result to the highest velocities and more water from the glacier. This leads to the highest competence.
What are the three types of sediment load?
When particles are eroded and transported by wind, water, or ice, they become part of the transport medium’s sediment load. There are three categories of load that may be transported by an erosional agent: dissolved load, suspended load, and bedload.
What factors affect sediment transport?
The two main flow factors in sediment transport are the settling rate and the boundary layer shear stress 27.
What are the 4 processes of transportation?
Transport
- Solution – minerals are dissolved in the water and carried along in solution.
- Suspension – fine light material is carried along in the water.
- Saltation – small pebbles and stones are bounced along the river bed.
- Traction – large boulders and rocks are rolled along the river bed.
What determines how much load a stream can carry?
The ability of streams to carry a load is determined by 2 factors: Competence and Capacity. Competence of a stream measures the largest PARTICLES it can transport. A stream’s competence increases with it velocity. The competence of a stream increases 4 times-when the velocity doubles.
What is the measure of the largest particles a stream can carry?
Competence
How do streams become graded?
The factors that make a river larger and the factors that make it smaller balance out. This is when it becomes a graded stream. But the slower, wider, and shallower parts of the stream deposit more material than they erode. The steeper areas will tend to get worn away, making them larger.
Which is a characteristic of a rejuvenated stream?
Characteristics of a rejuvenated river include water that flows rapidly with sloping sides that create steep cuts on the valley floor.
What is the smallest type of stream?
The smallest streams, rills, run in tiny channels also called rills. Rivulets and runnels run in gullies. Brooks and creeks run in washes or ravines or arroyos or gulches as well as small valleys with other names.
What are three characteristics of an old river?
Ridges are sharp, valleys are steep sided, and the landscape has maximum relief. Old age. The valley walls wear down, the river creates a broad flood plain, and begins to meander, or develop wide bends.
What are some characteristics of an old river system?
Old river – a river with a low gradient and low erosive energy. Old rivers are characterized by flood plains. Rejuvenated river – a river with a gradient that is raised by the earth’s movement.
What are the physical characteristics of a river?
Rivers shape the land as they flow over it. They may form valleys, floodplains, and deltas. When water flows through the mouth of a river into a large body of standing water, such as a lake or ocean, the river slows down. It deposits the sediment it is carrying near its mouth, generally forming a delta (Figure 4.10).
Why do most rivers have wider channels than most streams?
Why do most rivers have wider channels than streams? Streams feed into rivers and have more water for bigger channels. Large rocks that bounce along the bottom of a stream. They are rocks that need a lot of energy to carry them.
What happens as a river gets older?
As, the river gets older it accumulates larger number of water sources called as tributaries. Therefore, the volume of water will increase. This soil gets settled at the bottom increasing the channel of river flow. As, the river gets older the bottom bed becomes wider hence, will result in increased in water channel.
What are the 4 stages of a river?
Nearly all rivers have an upper, middle, and lower course.
- Young River – the upper course.
- Middle Aged River – the middle course.
- Old River – the lower course.
How can you tell the age of a river?
Scientists look at various geologic clues to help determine the age of a river, including how old the valley surrounding it is, how deep the water cuts into the riverbed, and the age of the sediments carried by the river.
Where does the water in lakes come from?
The water in lakes comes from rain, snow, melting ice, streams, and groundwater seepage. Most lakes contain freshwater. All lakes are either open or closed. If water leaves a lake by a river or other outlet, it is said to be open.
What is the main source of fresh water?
A. More fresh water is held in lakes on the Earth’s surface than is held in aquifers as groundwater.
How big does a body of water have to be to be a lake?
Definitions for lake range in minimum sizes for a body of water from 2 hectares (5 acres) to 8 hectares (20 acres) (see also the definition of “pond”). Charles Elton, one of the founders of ecology, regarded lakes as waterbodies of 40 hectares (99 acres) or more.
Why is it dangerous to swim in a reservoir?
Reservoirs are very dangerous places to swim and the government advises against people taking a dip in a reservoir. Here’s why: They tend to have very steep sides which makes them incredibly hard to get out of. They can be very deep, with hidden machinery that can cause injuries.
Is it dangerous to swim in a dam?
Stay away from the edge of water above and below hydroelectric dams and conveyance facilities. Surfaces can be extremely slippery and cause you to fall in the water. Don’t swim in any rapidly moving water. Never sunbathe, picnic or camp in an area which may become flooded due to dam operations.
Is Reservoir water clean?
Water Supply Reservoirs are designed to store the rain that falls during the wetter parts of the year, so that there is a continuous supply of water for the drier periods. The water from reservoirs must be cleaned before it is used. Find out more about water treatment and its distribution.
Why are lochs dangerous?
Apart from the small matter of Nessie lurking deep beneath the surface, the water is bitterly cold all year round – only around 5°C. In these low temperatures, you will quickly get hypothermia. So, in other words, wild swimming in Loch Ness is very dangerous!