Almost everything that humans do, produces waste. Waste may be in the form of surplus energy, like heat or light or substances produced during industrial processes. Sewage waste is generated by people themselves.
All these waste are released unto the environment, because there is nowhere else for it to go. When something contaminates the environment, we call it pollution.
Pollution can damage natural habitats, or disturb the life processes of organisms that live there. Pollution is a great problem that needs to be addressed with seriousness. Educating the youth about the facts may be the only way forward.
The processes we use to produce food and make things often create dangerous wastes, which can cause lasting damage if they are allowed to pollute the environment.
When fertilizers from farmland are washed into the sea by rain, they can cause ‘red tides‘ of poisonous algae. The nutrients in the fertilizers used by farmers which are washed out of the soil and into rivers when it rains allow these minute plants to reproduce rapidly, so they seem to fill the water and turn red.
There may be over 20 million algae per litre of sea water in a ‘red tide’. Poisons produced by the algae build up in animals like mussels and oysters, which feed on them. The poisons do not kill the birds and fish that feed on them. The poisons that accumulate in the fish can then kill the seals and dolphins that eat them.
Mercury is an extremely poisonous substance. When it leaked into the sea from a factory in Minamat bay in Japan, it built up in the bodies of tiny planktonic animals living in the water. The plankton were consumed by humans.
The concentration of mercury in the fish caused brain damage in some people, and deformities in unborn poisoned fish.
Traffic, which produces gases such as nitrogen oxide, carbon monoxide and ozone, as well as particles of soot, can cause asthma and other breathing disorders. Ozone gas drifts out of cities and can damage the leaves of trees in the countryside.
All types of vehicles that burn fossil release gases such as carbon dioxide. The carbon dioxide traps heat in earth’s atmosphere and contributes to global warming.
If global warming changes the climate it causes to natural ecosystems, because it alters patterns of rainfall and the timing of the seasons.
Some organisms in ecosystems may be able to cope with the new climate while others that are not able to adapt will disappear.
THE TROUBLE WITH TRANSPORT
These days, expect to be able to travel the world in just a few hours. But this freedom we use produces vast amounts of pollution, which harms our own lives and the natural environment of the planet.
Almost all cars, lorries, buses and trains use petrol, a fossil fuels burn they release gases, such as carbon dioxide which contribute to global warming. Global warming is damaging the environment we all live in.
The lives of people who live near large airports can be made unbearable by the constant noise from aircraft landing and taking off. Biologists are now concerned about sound pollution in the sea.
Whales keep in touch with one another by using ‘songs’ that travel for long distances under water. The increase in man-made sounds in the sea, from shipping, telecommunications and underwater experiments may drown the whales’ songs, so that they lose contact with each other.
POLLUTION FROM POWER
People living in the developed world use a huge amounts of energy, mostly in the form of electricity. To generate enough electricity, large numbers of power stations are required.
Many power stations burn fossil fuels, which cause dangerous air pollution. But there can be other harmful effects on the environment too.
Most power stations use water to help cool machinery, and many release warm water from their cooling systems into rivers or the sea. Seaweed and shellfish grow and reproduce rapidly in the warmth around the power station pipes.
Something they multiply so quickly that they clog the pipes and alter the natural balance of the ecosystem.
Many countries now use nuclear power to generate electricity. Nuclear power does not create air pollution in the same way as burning fossil fuels, but it has its own problems.
For example, in 1986, there was an explosion and fire in the nuclear reactor at Chernobyl in Ukraine.
A cloud of radioactive gas drifted across Europe from the reactor. Some radioactivity contaminated grass in the lake District in north western England.
When the radioactivity accumulated in their fresh. Luckily we know enough about the harmful effects of radiation to stop the meat from the sheep being eaten.
The amount of waste generated by large numbers of humans living together in a city is enormous. The pollution this waste causes when it is dumped in the environment can be very damaging.
The light produced at night by street lamps and buildings in cities can be seen from many kilometers away. Astronomers must set up telescopes in remote locations, well away from the light pollution on earth that interferes with their view of outer space.
Street lamps in cities can alter the Normal behavior of animals and can confuse birds. In cities, robins and blackbirds sometimes sing at night because the lights of the cities make them behave as though it was still daytime.
The light from street lights also attracts moths, so bats are sometimes seen hunting for moths around lights in cities.
Some animals have benefited from the waste we dump into the environment. Foxes and grey squirrels have spread from the countryside into many cities, where they scavenge for food in waste bins.
Large flocks of seagulls now feed on rubbish tips, where the food scraps that are thrown away in domestic east have become an important part of their diet.
When gulls flock around waste tips that are near airports, they become hazards as aircraft that are landing and taking off can suck them into their engines.