Unit 4 Review

4. pollution – The introduction of harmful substances into bodies of water.
6. pollution – The contamination of land with waste and harmful chemicals.
8. Revolution – The industrial movement that introduced high-yield crops and fertilizers.
11. – The process of making seawater drinkable.
12. depletion – The depletion of the Earth's protective atmospheric layer due to chemicals like CFCs.
14. – The clearing of trees for timber, agriculture, or urban expansion.
17. – The excessive removal of fish from oceans, leading to population declines.

1. – A farming practice that relies on a single crop type over large areas.
2. – The expansion of cities, replacing natural land with buildings and roads.
3. growth – The increase in human numbers, leading to higher demand for resources.
5. acidification – The acidification of seawater due to increased carbon dioxide absorption.
7. – The decline in soil quality and vegetation in dry regions due to overuse.
8. – The use of genetically modified crops to improve yield and resistance.
9. – The removal of minerals and ores from the Earth, often leading to land degradation.
10. use – The process of using water for agriculture, industry, and household needs.
13. pollution – The release of pollutants into the air, leading to respiratory issues.
15. – The presence of a dense, harmful haze over cities due to pollutants.
16. treatment – A process that treats used water to remove contaminants before reuse.