A Level Geography ~ Key Definitions

the properties of the earth's water, and especially its movement in relation to land.

the sequence of conditions through which water passes from vapor in the atmosphere through precipitation upon land or water surfaces and ultimately back into the atmosphere as a result of evaporation and transpiration

a set of things working together as parts of a mechanism or an interconnecting network

system in which mass or energy can be lost to or gained from the environment.

an isolated system which doesn't exchange any matter with its surroundings

an area or ridge of land that separates waters flowing to different rivers, basins, or seas.

the area from which rainfall flows into a river, lake, or reservoir.

rain, snow, sleet, or hail that falls to or condenses on the ground.

water that is caught and stored by vegetation

the part of rainfall or other precipitation which falls to the forest floor from the canopy.

the flow of intercepted water down the trunk or stem of a plant

the draining away of water from the surface of an area of land

the total volume of water flowing through a channel at any given point measured in cumecs

the process by which water on the ground surface enters the soil

water that either falls through gaps in the vegetation or which drops from leaves, twigs or stems

the passage of water, through a porous object, like rocks or soil

river discharge provided by ground water seeping into the river bed

water held underground in the soil or in pores and crevices in rock

the replenishment of an aquifer by the absorption of water

the level below which the ground is saturated with water

a place where water wells up from an underground source

the combined effects of transpiration and evaporation – loss of water from ground surfaces and vegetation into the atmosphere

location used by hydrologists or environmental scientists to monitor and test terrestrial bodies of water

overland flow, due to the ground being saturated with water

the tendency of water to flow horizontally across land surfaces when rainfall has exceeded infiltration capacity

a graph showing the rate of flow versus time past a specific point in a river, or other channel or conduit carrying flow

the time interval from the center of mass of rainfall excess to the peak of the resulting hydrograph

it reflects the increase in discharge from the catchment area, in response to a rainfall event

it represents the withdrawal of water from the storage built up in the basin

the highest point on the hydro graph when the rate of discharge is greatest

in a hydrograph, the line which seperates the baseflow from discharge due to rainfall, so the increase in discharge can be observed

a storm hydrograph with a steep rising limb and steep falling limb over a short period of time

the human use of land and the modification of the natural environment

The total length of all the streams and rivers in a drainage basin divided by the total area of the drainage basin

the degree to which rocks or soil allow water to fill pore spaces

the ability of a rock to absorb water and allow water to flow through cracks and joints

a body of permeable rock which can contain or transmit groundwater

the minimal point of soil moisture the plant requires not to wilt

the amount of soil moisture or water content held in the soil after excess water has drained away and the rate of downward movement has decreased

the total load actually transported by a river

the maximum size of material a river can transport

the total volume of water flowing through a channel at any given point and is measured in cubic metres per second

the speed that the river is flowing at

the ability of the channel to conserve energy that may otherwise be lost to friction

when fluid flows in parallel layers without any disruption between the layers

the mixing between layers of water characterised by chaotic property changes

the corkscrew flow of water in a meander

the process of scraping or wearing something away

mechanical erosion of the earth's surface caused when materials are transported across it by running water

erosion caused by acids in rivers and waves dissolving rocks by chemical action

a type of chemical weathering in which water dissolves minerals in rocks

erosion that occurs when the motion of water against a rock surface produces mechanical weathering

a process of transportation by rivers in which large material is rolled along the bed

a process of transportation by rivers in which material is picked up and carried along within the water itself

a process of transportation by rivers in which small particles bounce along the bed in a leap-frog movement

the taking up of river sediment into transport

sediment particles transported in a stream by rolling, sliding, or tumbling along the stream bed

small sediment carried in the water itself, by suspension

sediment which is carried in the water itself, by solution

an area of low-lying ground adjacent to a river, formed mainly of river sediments and subject to flooding

a channel that consists of a network of small channels separated by small and often temporary islands called braid bars

a small island in a braided river

a bend in a river

a deep place in a river

a rocky or shallow part of a stream or river where the water flows brokenly

the outside bank of a river which is continually undergoing erosion.

the gentle slope on the inside of the meander where depostion has taken place

an alluvial deposit that forms by accretion inside an expanding loop of a river

a place where water flows over a vertical drop in the course of a stream or river

a deep basin excavated at the foot of a waterfall by the action of the falling water

a fast-flowing and turbulent part of the course of a river

a narrow valley between hills with steep rocky walls and a stream running through it

a steep cliff, bank, or promontory

an embankment built to prevent the overflow of a river

a U-shaped body of water that forms when a wide meander from the main stem of a river is cut off

a deposit of sediment crossed and built up by streams

a triangular tract of sediment deposited at the mouth of a river due to a decrease in velocity

height at which a flood could occur

height at which a flood has taken place

the annual variation in the flow of a river

an estimate of the likelihood of an event, such as a flood or a river discharge flow to occur

overland flow and runoff which reaches the river quickly, causing a rapid rise in the level of the river