Humans and the environment

Question 1

Land degradation

Answer 1

• Land degradation is caused by multiple forces, including extreme weather conditions, particularly drought
• It is also caused by human activities that pollute or degrade the quality of soils and land utility

Question 2

Water pollution

Answer 2

• Pollution can enter water directly, through both legal and illegal discharges from factories.
• Spills and leaks from oil pipelines or hydraulic fracturing (fracking) operations can degrade water supplies.
• Wind, storms, and littering—especially of plastic waste—can also send debris into waterways

Question 3

What is chemical runoff?

Answer 3

Runoff is a term used to describe the flow over and movement away of water from one area and into a body of water, such as rivers or lakes

Question 4

What is irrigation?

Answer 4

Irrigation diverts water from rivers and lakes to crops