Landforms

Review-Key Vocabulary

DepositionDeltaOx Bow lakeCanyonValleyMeanderTributaryErosionWeatheringSediment

•Long depression in Earth’s surface- usually contains a river.•Process by which material is moved from the Earth’s surface.•Low, flat piece of land at the mouth of a river.•Curving changes of direction in a river or stream. •Breaking down of Earth’s materials.•A place where part of the river breaks away.•River or stream that does not reach the ocean.•Pieces of Earth’s material.•Fast-moving water, carries sand soils. As water slows down it deposits the sand in soil in a new location. •Deep narrow valleys with steep sides.

Flood PlainIs flat land near a river formed by deposition during floods. During a flood, water flows over a river’s banks. When the water leaves the swift movement of the river, it slows down. As the water slows down, it drops the sediment it was carrying. The rocks and soil becomes part of the flood plain.

FLOOD PLAIN

The River Tay is the longest river in Scotland and the largest volume river in Great Britain.

FLOOD PLAIN

FLOOD PLAIN

Review•Erosion occurs when natural forces move soil and small rocks from one place to another.•Wind, rain and other natural forces cause erosion.•Not all land erodes in the same way.•Erosion depends on the shape of the land.

Water MovementMoving water is one of the most common causes of erosion. Gravity pulls water downhill, this is why water flows downhill.As water moves from high ground to low ground, it weathers and erodes the rock it moves over.Fast-moving water often erodes rock faster than slow-moving water does.

SlopeThe speed of runoff water depends on the slope of the land it is moving over.Slope is the degree of change in elevation (height) over a length of land. A steep hill will have a large change in elevation over a length of land.A gently sloping hill will have a small change in height over the length of land.

Some landforms are made by the slope of the land and the amount of running water.The slope of the land affects the speed that water will flow over the land.Water will move faster when a hill has a greater slope. As water moves faster, it will also erode a steeper surface more quickly than a clatter one. The steeper the slope the more material that will be eroded.

Slope affects erosionThe slope of an area and the amount of water delivered to that area contributes to the rate (how much) of erosion.

What do you think?Does a steep hill have more erosion?Does a gently sloping hill have more erosion?Why?How does water move down a steep slope?How does water move down a gently sloping hill?What does water movement have to do with erosion?

Landforms from waterSome landforms that result from running water are :1.Canyons2.Deltas3.Alluvial fans

Grand Canyon

In the province of Tarragona, in Catalonia

Alluvial Fans

•Alluvial fans are fan-shaped deposits of water-transported material (alluvium). •They usually form where a fast flowing stream flattens, slows, and spreads. •At the end of a slope alluvial fans can form.

China

WindWind often carries small particles of sand and soil.The slope of land often affects what plants and trees grow (vegetation).Steep slopes are often bare. It is harder fro plant life to grow where soil erodes quickly (why).Wind erodes more rock and soil when there are no plants or trees(vegetation) to block the wind. Wind often blows down steep slopes very quickly (like what other force)Fast-moving air erodes the exposed (what) rock and soil faster that slow-moving air does.Fast-moving air can carry larger amounts of soil and dust.

VegetationPlants and trees can help slow down erosion (why). Soil on a steep slope is often missing nutrients(what) for plants to grow. (why do you think the soil would be missing nutrients?)Water also is an issue on steep slopes because it moves downhill very quickly and does not soak into the soil. This makes it harder for plants to grow there.

Giants Castle National Park, South Africa

Slope and Erosionslope video.htm

How can we use the stream tables to show that slope has and affect on erosion?