Human impact on Environment

It’s like a slinky…

• Humans impact their physical environment and the physical environment impacts humans.

• All human actions and all environmental changes have some

impact on each other

For example…• In the 1920s, people in America started to move out West in greater

numbers to farm.• They tore out the natural grasses to plant their crops.• There were not enough plants in the ground to hold in the soil• A very hot, dry summer in the 1930s led to dry ground and even less

living plants in the ground with roots holding down the soil• Heavy winds blew the soil around the farms. It was like walls of dust.• The dust walls settled and buried the remaining plants, resulting in

even less plants to hold down the soil… making the problem even worse.

• Many Americans lost everything they owned and had to leave their homes and start over.

Three-Gorges Dam

• The largest hydro-electric power station in the world

• Located on the Yangtze River in China• Covered farmland, homes, and threatened

wildlife when built

Before and After

Think about your neighborhood…

• 50 years ago• 100 years ago• 300 years ago• How have humans impacted the environment

in this time? • How has the environment impacted humans

in this time?