contamination = pollution by poisons or dangerous elements
The atmosphere in large cities is often contaminated by smog, as we can see in China.

the biosphere = the relationship between all living things on the planet
Children should be educated on the biosphere through field trips and practical experiments.

emissions = gases entering the atmosphere
Scientists spend their whole careers studying the effect of emissions on the climate.

pollutant particles = microscopic elements of pollution
I remember going to a factory and seeing the snow-covered with pollutant particles.

run-off = water that runs from the ground into rivers and lakes
We should try to collect and use more run-off water, to avoid having to recycle water so much.

the water cycle = the natural process of water moving from clouds to rain and seas
Scientists believe the water cycle is responsible for various natural events, especially in coastal areas.

aquifers = underground, natural water stores
My family has a well that connects to an aquifer, giving very pure water.

filtration = the process of filtering and removing impurities
Water filtration might be a solution to water shortages in very hot countries.

water table = the layer of water below ground
In my town, the water table is very high, and water will appear in even a small hole.

tainted = polluted or contaminated
The Mediterranean is badly tainted in some areas by sewage pollution.

soil erosion = the loss of soil by wind and rain activity
Deforestation has increased soil erosion seriously in Brazil.

logging = cutting down trees for timber and industrial use
Logging has endangered many species throughout the world.

dumping = leaving waste deliberately without storing or treating it
In most countries, dumping rubbish is a criminal offense.

waste = any material not wanted or needed after a process
In my country, we use the waste from cotton manufacture for lighting fires.

landfills = organized areas where waste is buried in the ground
Surprisingly, Britain still spends most of its domestic waste to landfill sites.

waste processing = recycling or reducing waste into manageable forms
My brother has a waste processing company, which is subsidized by the local authority.

poaching = illegally hunting and killing animals
Elephant poaching should be a much higher priority for the world authorities, as elephants are an endangered species.

habitat loss = destruction or disappearance of an animal’s natural home
Logging has caused substantial habitat loss for wildlife in many countries.

food chain = the natural system of animals eating other animals and plants
The food chain has been disrupted by the loss of certain species, with widespread impacts on all animals.

dwindling numbers = (to dwindle = to steadily decline in quantity)
States seem to have dwindling funds to pay for animal sanctuaries, although they are still able to pay for government officials and their perks.

extinction = the final death of all animals in a species
Dinosaur extinction may have been caused by a meteor or volcano, but scientists seem unsure about this.

famine = a situation where there is a lack of food in an area for a long time Many singers help make charity songs to raise funds for famine relief.

drought = similar to famine, but a lack of water
Drought in central Africa can continue for many years, apparently. irrigation = supplying water to land for agriculture
If we want quick solutions to famine, better irrigation and farming methods would probably be the first step.

catastrophe = a great disaster affecting many people
The continuing destruction of the rainforests is a catastrophe for the global biosphere.

exacerbated (= to exacerbate = to make an existing problem worse, accidentally or deliberately)