River Environments Keywords

Abstraction: the taking of water from rivers, lakes and from below the watertable (aquifers)

Attrition: A process of erosion. The material is moved along the bed of a river, collides with other material, and breaks up into smaller pieces. 

Aquifers: permeable rock that can transfer or store water below ground (ground water)

Base flow: the usual level of a river, the part of a river's discharge fed by groundwater

Catchment area=Drainage basin

Channel network: the pattern of linked streams and rivers within a drainage basin

Clean water: water that is fit for human consumption and is therefore relatively free from pollutants

Condensation: when water vapour is cooled and changes state to form water droplets

Confluence: where two rivers/streams meet

Corrasion: a process of erosion, sometimes known as abrasion. This is when fine material rubs against the river bank. The bank is worn away, by a sand-papering action called abrasion, and collapses. 

Corrosion: a process of erosion. Some rocks forming the banks and bed of a river are dissolved by acids in the water

Cumecs: cubic metres per second, the unit for river discharge

Dam: a large structure, usually of concrete, sometimes earth, built across a river to hold back a large body of water (reservoir) taken for human use

Deposition: the dropping of material that was being carried by a moving force, such as running water

Discharge: the quantity of water flowing in a river channel at a particular location and time

Drainage basin: It is a water system involving external inputs and outputs, where the amount of water in the system varies over time. It is the area where water from precipitation (rain/snow..) drains downhill into a common body of water such as a river or lake. [The area drained by a river and its tributaries.]

Erosion: the wearing away and removal of material by a moving force, such as running water

Flood plain: the flat land lying either side of a river which periodically floods

Hydraulic action: a process of erosion. The sheer force of water hitting the banks of a river

Hydrograph: a graph showing the discharge of a river over a given period of time

Hydrological cycle: the global movement of water between the air, land and sea

Impermeable: if a material is impermeable, it does not allow water to pass through it

Interlocking spur: a series of ridges projecting out on alternate sides of a valley and around which a river winds

Levee: a raised bank of material deposited by a river during periods of flooding

Mass movement: the movement of weathered material down a slope due the force of gravity

Meander: a winding curve in a river's course

Oxbow: a horseshoe-shaped lake once part of a meandering river, but now cut off from it

Pollution: the presence of chemicals, dirt or other substances which have harmful or poisonous effects on aspects of the environment such as rivers and the air

Reservoir: an area where water is collected and stored for human use

River regime: the seasonal variations in the discharge of a river

Saltation: a process of transportation. smaller stones are bounced along the bed of a river in a leap-frogging motion

Solution: a process of transportation. Dissolved material is transported by the river.

Suspension: a process of transportation. Fine material, light enough in weight to be carried by the river. It is this material that discolours the water.

Stores: features, such as lakes, rivers and aquifers, that receive, hold and release water

Stormflow: the increase in stream velocity caused by a period of intense rainfall

Stream velocity: the speed at which water is flowing in a river at a given location and time

Traction: a process of transportation. Large rocks and boulders are rolled along the bed of the river

Transfers: the movement of water between stores in the hydrological cycle

Transport: the movement of a river’s load

Waterfall: where a river’s water falls vertically, as where a band of hard rock runs across the river channel

Watershed: the boundary between neighbouring drainage basins

Weathering: the breakdown and decay of rock by natural processes, without the involvement of any moving force