Edexcel IGCSE Geography River Environments

Abstraction

Removal of water from rivers, lakes or groundwater for human use.

Base Flow

That part of a river's discharge fed by groundwater.

Channel

The part of a valley floor occupied by the flowing water of a stream or river.

Channel network

The system of tributary streams that join increasingly larger river channels in a drainage basin.

Dam (& Reservoir)

A barrier (made on earth, concrete or stone) built across a valley to interrupt river flow and create a man‐made lake (reservoir) to store water.

Discharge

The quantity of water that passes a given point on a stream or river‐bank within a given period of time.

Drainage Basin

The area drained by a river and its tributaries, bounded by a watershed.

Erosion

The wearing down of the land by water, ice, wind and gravity.

Flood

When river discharge exceeds river channel capacity and water spills out of the channel onto the floodplain and other areas.

Flood Plain

That part of a valley floor over which a river spreads during seasonal floods.

Hydrograph

A graph on which variations in a river's discharge are plotted against time.

Hydrological Cycle

The unending movement of water between land, sea and atmosphere.

Impermeable

Rocks that do not allow water to pass through them.

Interlocking spurs

A series of ridges projecting out on alternate sides of a valley and around which a river winds its course.

Landform

A physical feature with recognizable characteristics e.g. waterfall, meander, formed by specific processes such as erosion or deposition.

Levee

A bank of sediment formed along the edge of a river channel deposited by floodwater.

Mass movement

The movement of weathered rock down slope without the direct action of running water.

Meander

A pronounced bend in a river.

Oxbow Lake

A crescent shaped lake which form when a meander bend is cut off from the main river channel.

Precipitation

The deposition of moisture on the Earth's surface, in the form of dew, frost, rain, hail, sleet or snow.

River Regime

The variation (seasonal pattern) in river discharge over the course of a year.

Shortage/ Surplus

Areas where water supply is lower / higher than water demand from humans

Store

Places within a system where materials or energy are held for a time.

Streamflow

The flow of surface water in a well‐defined channel.

Transfer

Flows of water between stores in the hydrological cycle.

Valley

A linear depression in the landscape formed by erosion, usually with a river channel at its lowest point.

Velocity (stream)

The speed of water flow in the river channel.

Water quality

A measure of how fit for human consumption water is. Polluted water has low water quality.

Watershed

The dividing line between one drainage basin and another.

Waterfall

A river landform created by erosion, where water drops steeply/vertically as it flows over a cliff like feature.

Weathering

The chemical alteration and physical breakdown of rock in situ.