Grade 8 Integrated Science Chapter 20 Lesson 1 on people and their impact on the environment. This lesson is a short introduction of the positive and negative impact of human. Students should consider the net impact of the 7 billion people on earth and the effect that individuals can make.
*This outline follows the Chapter 20.1 presentation slides.
Outline: Chapter 20.1: People and their Environments
1. Chapter 20 Lesson 1: People and the Environment –p718-722 - Page1
New Vocabulary
• Population (719) – all the members of a species living in a given area
• Carrying Capacity (720) – the largest number of individuals of a given species that Earth’s resources
cam support and maintain for a long period of time
Population and Carrying Capacity
• For scientist, a population is all the members of a
______________ living in a given area.
• We are a population of _________________! (hurray)
• There are also ___________ and ____________ that make
up separate populations in your area.
The Human Population
• Earth was once home to relatively few humans
• Today, about ________________ billion people live on Earth. The greatest increase in
human population occurred during the last few centuries
Population Trends
• A sudden rise in human population that has happened in recent history is called a
______________________ _____________________.
• Look at the chart
• What caused this sharp increase?
o _______________________
o _________________________
o Technological advancements
In 1 hour about 15000 babies will be born
2. Chapter 20 Lesson 1: People and the Environment –p718-722 - Page2
Population Limits
• All living things have certain needs.
• What do humans need?
• Where do all the materials we use for products come from?
• Does Earth have enough resources to support an unlimited number of humans?
• Earth has limited resources
o It cannot support a population of any species in a given environment beyond its
carrying capacity
• Carrying capacity is the largest number of individuals of a given species that earth’s
resources can support and maintain for a ___________ ______________.
o If the human population continues to grow beyond Earth’s carrying capacity,
eventually Earth’s _______________________ will run out.
Impact of Daily Actions
• As of 2012, the human population is _____________________ billion
o Everyone is using resources
o Think, everyday people should be drinking 2-3 liters of liquids a day
o That’s 14,000,000,000L of liquid consumed in a day used just for drinking (if
everyone got the necessary amount)
Consuming Resources
• Like most people, I hope you are taking a shower every day. What resources are needed to
make that happen?
o The _____________________ in the pipes are obtained through mining, which
causes pollution and destroys habitats
o ____________________ is needed to transport those metals, which releases
pollution into the atmosphere
o You probably use a _____________________ towel. Fertilizers often used to grow
crops run off into water and affect overall water quality
• Think about all the activities you do in a week and the resources needed to make them
possible. Then, multiply that by 7 billion.
o This why using resources wisely, even at a personal level, can help Earth
Positive and Negative Impacts
• Not all human activities have a negative impact on the environment.
• What are some positive and negative impacts of humans?