Waste management
As the human populationAll of the members of a single species that live within a geographical area. increases, the volume of waste and pollutionContaminating the air, water or ground with harmful substances. that is produced also increases. Polluting an ecosystemThe living organisms in a particular area, together with the non-living components of the environment. harms or kills the organisms that live within it.
Modern society is more consumable, which means humans manufacture more products and replace them more often. This consumption is not sustainableAn activity which does not consume or destroy resources or the environment.. Many natural materials, including fossil fuels, will soon run out and scientists argue that there is already too much waste.
Water pollution
In some parts of the world, open sewers can lead into water courses, such as streams and rivers, which can cause serious illness in humans that may drink the contaminated water.
Some farmers use too many fertilisers, which can run off fields during heavy rain. This can pollute nearby streams and rivers leading to eutrophication'Hyper-nutrition' resulting from fertiliser pollution of aquatic ecosystems.. Some water pollution even comes from toxicPoisonous. chemicals released illegally by factories.
Air pollution
combustionThe process of burning by heat. of fossil fuels and other fuels releases carbon dioxide. This contributes to the greenhouse effectThe retention of heat in the atmosphere caused by the build-up of greenhouse gases. and leads to global warmingThe rise in the average temperature of the Earth's surface. . It also releases sulfur dioxide and nitrogen oxides which can cause acid rain. Air pollution can also be caused by tiny particulates from smoke which can cause smogA type of pollution that is a mixture of smoke and fog.. Some of the world's major cities like Delhi in India and Karachi in Pakistan have dangerously high levels of air pollution.
Land pollution
The rubbish we throw out that is not recycledUsed materials that have been reprocessed to make new materials. goes into a land fill. These are huge holes in the ground into which our rubbish is dumped. Some things like batteries cannot be put into landfill sitesPlaces where refuse is buried underground. because of the toxic chemicals they contain. They must be recycled. Other land pollution comes when some people dump rubbish in public or other private places, often to avoid paying for it to be disposed of. This is caused fly tipping and is illegal.
Land use
The larger the human population gets, the more land we require. More houses must be built, more resources found, more food must be grown and more waste is produced. This often means less space and fewer resources for other animals and plants.
Often biodiversityThe range of animals and plants in a given area. is significantly reduced when land is cleared for human uses, such as building, quarrying, farming and waste disposal. Think about the reduction in biodiversity, which occurs when an area of rainforest is cut down to grow crops.