The Influence of Human Activity on the Environment

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The Influence of Human Activity on the Environment

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Improvements in agriculture health and medicine have produced a dramatic rise in the human population

This increase in population size leads to an increase in pollution and higher demand for the world’s resources

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Humans are using up the earth’s resources, including fossil fuels.

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Burning fossil fuels in cars and power stations produces carbon dioxide, sulphur dioxide and other greenhouse gases

carbon dioxide traps heat in the atmosphere and causes the temperature of the earth to rise.

This leads to disruption of the weather patterns eg drought, floods

Some weeds may thrive on the extra carbon dioxide while other plants are killed

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Sulphur dioxide will dissolve in rain producing Acid Rain

Acid rain damages trees and pollutes rivers and lakes.

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Acid rain causes erosion of buildings and statues particularly if they are made of limestone

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Deforestation

In may countries people are chopping down forests to provide timber or space for agriculture for the growing population

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This causes several problems

Burning the timber increases the level of carbon dioxide in the air

Less trees means less carbon dioxide absorbed for photosynthesis

Soil is eroded as it is exposed to the wind and rain

Less water is transpired into the atmosphere

Many animal and plant habitats are destroyed causing extinction of species

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Intensive Farming

Farming has become more intensive to provide a higher % yield from land

Many people regard intensive farming of animals to be cruel

In order to produce more food from the land farmers have to use more fertilisers and pesticides

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Problems with Fertilisers

Fertilisers enable farmers to grow more food as they are replacing the nutrients removed from the soil by plants

However, if too much fertiliser is added and it then rains, the fertiliser finds its way into rivers and lakes