Geography-River Erosion, The Water Cycle and Drainage Basin

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Evaporation

Water being converted from a liquid to a gas due to the heat of the sun.

Transpiration

Water vapour being 'breathed out' by plants into the atmosphere.

Condensation

The formation of clouds or due to water vapour in the atmosphere being cooled, so that it state into tiny liquid water droplets.

Precipitation

The transfer of liquid water from the atmosphere to the ground in the form of rain, snow, sleet or hail.

Surface runoff

Water that flows over land until it reaches lakes, rivers, or other bodies of water.

Infiltration

The process by which water on the ground surface soaks down into the soil.

Percolation

The downward movement of water through soil and rock due to gravity.

Throughflow

Water flowing through the soil layer parallel to the surface until it reaches a stream or body of water.

Groundwater Flow

Water flowing from an aquifer into a body of water.

Source

The place where a stream or river begins.

Drainage basin

The area of land from which a single stream or river and its tributaries drains all of the water.

Watershed

An area or ridge of land that separates waters flowing to different drainage basins.

Tributary

A stream or river that flows into a larger river.

Confluence

The place where 2 rivers meet.

Floodplain

The area subject to flooding adjacent to the river.

Channel Network

The pattern of linked streams and rivers within a drainage basin.

Mouth

Where the river flows into the sea.

Vertical Erosion

When the river channel or valley becomes deeper.

Lateral Erosion

When the river channel or valley becomes wider.

Hydraulic Action

The force of the water breaks rock particles away from the river channel.

Abrasion

When the pebbles being transported wear away the river bed and banks (sandpaper effect).

Attrition

When rocks that the river is carrying knock against each other, which makes them break apart to become smaller and more rounded.

Solution

When rock particles can be dissolved by the river.

Saltation

When particles are carried by water in short jumps due to the flow's energy. It happens in fast-flowing rivers and can cause erosion and sediment movement.

Suspension

The transport of sediment particles, such as silt and clay, within the water column.

Traction

When larger particles are rolled or dragged along the riverbed.