Unit 4 - Water and its Management

Key terms in the textbook & revision guide

Sanitation

The conditions ^^necessary^^ for health (such as providing clean drinking water and the safe disposal of sewage)

Precipitation

The process in which ^^liquid water^^ (rain) or ^^ice particles^^ (snow or hail) ^^fall to Earth^^ due to gravity

Surface run-off

^^Precipitation^^ that flows ^^over the ground surface^^, eventually finding its way into streams and rivers

Interception

^^Precipitation^^ that doesn’t reach the Earth’s surface due to the ^^obstruction by trees and plants^^

Infiltration

^^Precipitation^^ which soaks into sub-surface soils and moves into rocks through cracks and pores (water ^^seeps into the ground^^)

Through-flow

The process by which ^^infiltrated water flows through the soil^^

Groundwater Flow

The process by which infiltrated water flows ^^through rocks^^

Evaporation

Water from oceans, seas and other water sources which change ^^from water droplets to water vapour^^ in the atmosphere due to ^^heat^^

Transpiration

The movement of water ^^up plants^^ and its subsequent ^^loss as water vapour from their leaves^^

Condensation

^^Water vapour^^ converted back ^^into liquid or solid^^ due to a ^^decrease in temperature^^ (with increasing height by air currents)

Surface Water

Water in ^^lakes, rivers and swamps^^

Ground Water

Water in the ^^soil^^, and in ^^rocks^^ under the surface of the ground

Aquifers

Water stored in ^^porous rocks^^ under the ground

Artesian Aquifers

^^Aquifers^^ in which the water is ^^under pressure^^

Potable

Safe to drink

Reservoirs

^^Artificial lakes^^ used as a source of ^^water supply^^, usually created behind a dam or by the side of a river **(bank-side reservoir)**

Service Reservoirs

^^Reservoirs^^ where ^^potable water^^ is stored (i.e. water towers & cisterns)

Wells

A ^^hole^^ bored or dug into ^^rock^^ to reach the water stored in them

Desalination

The ^^removal of salt^^ from seawater

Distillation

Water which is ^^boiled^^ and released as ^^vapour^^, leaving salt behind

Reverse Osmosis

Pumping water at a ^^high pressure^^ through a ^^fine membrane^^

Water-rich countries

Countries with ^^plentiful^^ ^^freshwater^^ supplies

Water-poor countries

Countries with ^^scarce^^ ^^freshwater^^ supplies

Water Conflict

Conflict between countries, states or groups over an ^^access to water resources^^

Physical water scarcity

^^Not enough water^^ to meet both human demands and those of ecosystems to function effectively

Economic water scarcity

A situation in which there is ^^enough water available but the money does not exist to extract and or treat^^ enough of it for human needs

Sewage

^^Waste matter^^ that is carried away in ^^sewers or drains^^ from domestic (or industrial) establishments

Biomagnification

Increases concentration of a ^^toxic substance^^ in the tissues of organisms at successively ^^higher levels in a food chain^^, causing illness

Bioaccumulation

The accumulation of a ^^toxic substance^^ in the tissue of a ^^particular organism^^

Flush toilet

Uses a ^^holding tank for flushing water^^, and a ^^water seal^^ that prevents smells

Pour toilet

Toilets which have a ^^water seal^^ but uses water poured by hand for flushing

Pit latrine

Type of toilet that ^^collects human faeces^^ in a hole in the ground that is sometimes ^^ventilated^^ to take away smells

Composing toilet

A dry toilet in which ^^vegetable waste, straw, grass, sawdust and ash^^ are added to the ^^human waste^^ to produce ^^compost^^

Water treatment

Water is made potable by undergoing coagulation treatment, being filtered and/or disinfected

Chlorination

^^Chlorine^^ used as a ^^disinfectant^^ to kill remaining pathogens

Water-borne disease

Diseases which are spread by ^^consuming contaminated water^^ due to poor sanitation and untreated sewage, or by washing food, pots. and pans, or hands and face in dirty water

Cholera

^^Intestinal^^ infection that causes ^^severe diarrhoea^^ that may lead to dehydration and eventually death

Water-bred dieases

Diseases where the ^^carrier breeds in water and spreads the disease by biting its victims^^

Malaria

A life-threatening disease which is transmitted through the bite of an infected ^^mosquito^^ (vector) that carries the ^^Plasmodium parasite^^

Pathogen

An ^^organism^^, including bacteria and viruses, that ^^can cause disease^^

Vector

An organism that ^^carries^^ a disease-producing organism (such as the mosquito which carries the malarial parasite)

Effluent

A discharge of liquid waste

Dieback

The ^^death of a tree or shrub^^ that starts at the ^^tip of leaves or roots and spreads towards the centre of the plant^^, caused by unfavourable environmental conditions or disease

Leaching

The ^^movement of a soluble chemical or mineral^^ ^^away from soil^^, usually caused by the action of rainwater

Algae

Plant-like, photosynthetic organisms that ^^lack true stems, roots and leaves^^

Algal bloom

^^The rapid growth of algae in water^^, caused particularly by a surge of nutrients

Eutrophication

A sequence events starting with enrichment of water by mineral nutrients or organic mater that leads to reduction in oxygen levels in the water and the death of fish and other animals