Ch.2.6 Flashcards
Although water covers about 70% of the Earth’s surface, most of it is sea water and only about ______% is fresh water
3
Only _________% of the fresh water on Earth is in rivers and lakes
0.4
Water is a ____________ resource.
Precious
In many parts of the world, fresh water supplies cannot meet our needs. ______________ _________ will make the situation worse.
Population growth.
It is important that we must use water _____________ and not waste it.
Wisely
As water resources are limited, we need to ____________ water in daily life.
Conserve.
Names 7 ways to conserve water at home.
Hints: take, run, wash, use, repair, save, turn
- Take a short shower instead of a bath or a long shower
- Run the washing machine only when you have a full load
- Wash dishes in a basin rather than under running water
- Use water saving devices such as a washing machine with the Grade 1 efficiency label
- Repair any dripping taps as soon as possible
- Save water used to wash fruits and vegetables for watering your plants
- Turn off the tap instead of letting the water run while you brush your teeth
Human activities produce various kinds of pollutants. If pollutants are discharged directly into rivers, lakes or seas, they may cause ___________________.
Water pollution.
Name the three main sources of pollution.
Discharging waste water directly, littering and dumping solid waste and oil spill accidents
A lot of waste water is produced from __________, ___________, _________ and ______________
Homes, restaurants, farms and factories
The waste water from different sources contains different ____________.
Pollutants.
Harmful effects of discharging waste water directly:
- _______________, ______________, ______________ and _____________ promote the growth of algae
- If algae grows rapidly in a short period of time, they use up the _________ in water
- Fish and other aquatic life may die due to _______________
- _____________ and toxic chemicals cause harmful effects to nearly all life forms
Human waste, animal waste, detergents, fertilisers, oxygen, suffocation, pesticides
Some people pollute the environment directly by throwing solid waste on beaches and in rivers and seas, such as:
* Plastic \_\_\_\_\_\_\_\_ and \_\_\_\_\_\_\_\_\_\_ * \_\_\_\_\_\_\_\_\_\_\_\_\_\_ nets
Bags, bottles, fishing
Harmful effects of littering and dumping solid waste:
* Solid waste can be \_\_\_\_\_\_\_\_\_\_\_\_\_\_ to animals, eg: * Sea lions and sea turtles may get trapped in \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ * Fish may mistake \_\_\_\_\_\_\_\_\_\_\_\_\_ for food
Hazardous, fishing nets, plastic
Oil from accidental spills of ____________ ships causes series pollution.
Oil tanker
Harmful effects accidental oil spills:
* Oil floats on water and prevents \_\_\_\_\_\_\_\_\_\_\_\_ from dissolving into sea water * Fish die from lack of \_\_\_\_\_\_\_\_\_\_\_ * Sea birds cannot fly when their \_\_\_\_\_\_\_\_\_\_\_\_\_ are covered with oil * They also cannot use their feathers to keep \_\_\_\_\_\_\_\_\_\_\_\_ and may die of cold
Oxygen X2, feathers, warm
- Controls of water pollution
- Use only the needed amount of ___________ for washing
- Take part in a ________________ campaign
- Do not throw ____________ into seas and onto beaches
- Dispose of _____________ waste properly in laboratories
- Do not dispose of solid waste in ____________ or street drains
Detergent, beach clean-up, rubbish, chemical, toilets
The Hong Kong Government has also taken practical and __________ measures to reduce water pollution, eg:
* Laws have been set up to restrict the discharge of ____________ __________ _________ from restaurants, farms and factories
legal, untreated waste water
Waste water treatment in Hong Kong:
About __________ million cubic metres of waste water are produced every day. Before discharging the waste water into seas and rivers, the waste water has to be treated to _______________ ____________ ______________
2.9
Reduce water pollution
The ________________ _____________ ______________ (_ _ _) is responsible for the treatment of waste water.
Drainage services department, dsd
The department that is responsible for the treatment of waste water operates over _ _ _ ________________ _____________ ______________ including _ _ _____________ _______________ ____________. In each of these plants, sewage is treated to remove the ________________ ______________ it contains.
200 sewage treatment facilities, 67 sewage treatment plants, harmful substances
Harmful chemical wastes from factories are collected and sent to the ____________ _____________ _____________ ______________ (_ _ _ _) for treatment. Chemical wastes from __________________ ______________________ are also treated in the same place.
Chemical waste treatment centre, school laboratories
Harbour area treatment scheme
- to improve the water quality of ___________ ________, the Hong Kong government introduced the harbour treatment scheme (_ _ _ _) in 1990s
- since the implementation of _ _ _ _, the _________ ___________ of the Victoria Harbour has improved: the overall _________________ level in the harbour has reduced ______________
Victoria Harbour HATS HATS Water quality E. Coli Significantly