Topic 4 SL

Groundwater

Water stored beneath the Earth’s surface in soil and rock crevices.

Saline

Salty.

Hydrological cycle

The biogeochemical cycle by which water continuously cycles on, above, and below the surface of the Earth.

Evaporation

The transformation of a liquid into a vapor, for example liquid water into water vapor.

Transpiration

The release of water by plants as water vapour.

Evapotranspiration

The process by which water moves from land to the atmosphere by evaporation and from plants by transpiration.

Advection

Wind-blown movement of water vapor or condensed/frozen water droplets (clouds).

Sublimation

The transformation of solid to vapour, for example ice to water vapour.

Condensation

The transformation of a gas into a liquid, such as water vapor into liquid water.

Precipitation

Water that falls to the Earth’s surface or condenses in various forms of rain, snow, hail, or sleet; in chemistry it describes the transformation of a dissolved substance to an insoluble solid.

Infiltration

Movement of water from the surface into the soil.

Percolation

The transfer of water downward through layers of soil or rock.

Run-off

The transfer of water from a solid surface into a body of water.

Surface run-off

Flow of excess water over land after rainfall, melting of snow, etc.

Streamflow

Flow of water in a river or artificial body, such as a canal.

Irrigation

The transfer of water by humans from surface or groundwater storages to crops.

Drought

A long period of abnormally low rainfall that leads to a shortage of water for organisms in an area.

Drip irrigation

The controlled supply of water directly to individual plants through a network of tubes or pipes.

Fertilisers

Substances mainly composed of nitrates, phosphorus, and potassium, added to increase soil fertility.

Eutrophication

The natural or artificial enrichment of a body of water, particularly with nitrates and phosphates, that results in depletion of the water’s oxygen content. Eutrophication is accelerated by human activities that add detergents, sewage, or agricultural fertilizers to bodies of water.

Algae

Aquatic organisms that perform photosynthesis to produce their own food.

Flash flood

Unexpected intense flood caused mainly due to excessive rainfall.

Deforestation

The action of removing trees from a wide area of land.

Sedimentation

The process of particles settling to the bottom of a body of water.

Afforestation

Planting large numbers of trees on land which has few or no trees.

Urbanization

The process of making a landscape more built-up, industrialized and dominated by close human settlements.

Sponge Cities

Urban environments constructed to prevent run-off and flooding, and to recharge groundwater, by provision of green spaces.

Water Security

Having access to sufficient amounts of safe drinking water.

Water Scarcity

Limited availability of water to human societies.

Mitigation

Action to reduce the severity of something; e.g. strategies involve reduction, stabilization of GHG emissions and their removal from the atmosphere.

Dams

A wall with gates built across a water body to stop the flow and collect the water.

Reservoirs

An area where water is collected and stored for later use.

Rainwater Catchment

An area to which excess rainwater drains.

Desalination

Processes that remove the excess salt and other minerals from water in order to obtain freshwater suitable for consumption or irrigation.

Ways to Increase Supply of Water

• Dams and reservoirs

• Desalination technology

• Improving natural wetlands

• Rainwater Catchment systems

Ways to Reduce Demand for Water

• Metering

• Rationing

• Products that uses less water

• Grey-water recycling

Metering

Measuring and recording a quantity using a meter. This can be used to keep track of water usage in households.

Rationing

Limiting the quantity a person or group may use.

Grey-Water Recycling

Waste water from showers and sinks can be recycled for purposes other than drinking, such as water plants.

Ways of Conserving Water in Food Production

• Drip irrigation

• Greenhouses

• Aquaponics

• Drought-resistant crops

Aquaponics

A form of aquaculture that combines raising fish in tanks with the culture of soilless plants. Waste water from fish tanks goes to plants, then the purified water from plants goes back to fishes.

Phytoplankton

Microscopic aquatic plants that carry out photosynthesis.

Natural Capital

The natural resources that have economic value or provide a service to humans.

Natural Income

Materials in nature that can be used by humans to meet their needs and wants.

Maximum Sustainable Yield (MSY)

The largest yield or catch that can theoretically be taken from a species’ stock without permanently depleting the stock.

Fishing quotas

A permitted or required quantity, for example of fish that can be caught in a year by a particular ship.

Ocean acidification

A reduction of the ocean’s pH over time (becoming more acidic), caused mainly by dissolution of CO2 from the atmosphere.

Coral Bleaching

Occurs when corals expel the colorful algae living within the coral polyps, making the coral turn white.

Marine Protected Area

Region in the ocean where human activities, such as fishing or development, are regulated to conserve and protect marine ecosystems.

Aquaculture

The farming of aquatic organisms, including fish, mollusks, crustaceans and aquatic plants.

Why are fish species overexploited?

• Lacking fishing regulation

• Hi-tech fishing gears catch unsustainable amount of fishes

• Global markets hides fishes origins

Fishing sustainability is affected by…

• Number of fish caught in a time period.

• Damage done to habitats from fishing.

• Level of bycatch

Stakeholders in Managing Fish Stocks

• Countries (international cooperation)

• Individual action

• NGOs.

• National governance

Negative Impacts of Aquaculture

• Harm to local habitats

• Diseases

• Antifouling agents can be harmful

• Fishmeal comes from wild fish