1. Topic 3: Environmental Choices
Grade 7 Unit 1
Topic 3: Environmental Choices

2. Objectives I can identify examples of human impacts on ecosystems
I can analyze the relationship between the impact of humans and their needs and desires

3. Introduction
Natural resources are all materials and products found in nature that are useful or necessary for living beings to meet their basic needs.
All living organisms use natural resources.
They are grouped into 2 categories: renewable (can be replaced naturally) and non-renewable (cannot renew itself naturally within a reasonable period)

4. Introduction cont..
Name 4 natural resources

5. Your Ecological Footprint
Surface area (land and water) needed to supply all resources used for a given population and absorb all the waste produced by that same population.

6. Impact Here and There cont.
The Ecological Footprint of a 10 km trip:
122 m2
303 m2
1530 m2

7. Activity – look at figure 1. 23
Activity – look at figure Which of the two photos have a smaller ecological footprint and why?

8. Sustainability means that natural resources are being renewed at least as quickly as they are used and that all waste is fully absorbed.

9. Impact Here and There
A responsible use of natural resources requires sustainability. Otherwise, it used up faster than the resources nature can renew itself, and pollutes the environment.
It is important to remember that we not only depend on nature, we are part of nature.
People who live in North America and other wealthy countries use far more than their share of Earth’s natural resources.
North American’s do not live in a sustainable manner, and this causes concern over the dwindling resources on Earth.

10. Impact Here and There cont.
Activity – Read « Pause and Reflect » on page 31.

11. Impact Here and There cont.
If we divide the Earth by the population of the Earth, there is approximately 1.5 hectares per person. This area should provide all the resources we need to survive for each person and absorb all our garbage.

12. Impact Here and There cont.
In Canada, our ecological footprint is three times the normal average. The Canadian average is approximately 4.3 hectares per person!
If all living things continue to live the way we do now, we would need at least 2 more planets the size of Earth to provide all the resources we need and absorb all our garbage.

13. Activity – Calculate your ecological footprint with this web site :

14. Give three things that a Canadian can do to reduce their impact on the environment and reduce the size of their ecological footprint?  
Reduce the amount of energy you are consuming
Reduce the number of things you buy
Reduce the amount of garbage you produce
What can you personally do to reduce your ecological footprint?

15. Reduce, Reuse, Recycle 1. Reduce: the amount of garbage you produce.
Avoid buying individually wrapped items, disposable items, and overpackaged items.

16. Reduce, Reuse, Recycle cont.
2. Reuse: products rather than throwing them away.
Use plastic containers to store leftovers.
Hand down your clothes to younger siblings, or give them to charity/ a consignment store.
Use refillable bags/containers when you pack your lunch or go shopping.

17. Reduce, Reuse, Recycle cont.
Recycle: turns a product, that cannot be reused in its current form, into something else.
Composting kitchen scraps.
Taking newspapers, cardboard, jars, cans, and other recyclable items to the recycling depot.
Buy products made with recycled materials.

18. Recovery Sometimes considered the fourth R in Reduce, Reuse, Recycle.
Recovery concerns the use of technology to get back precious natural resources or those that could cause great harm to the environment.
Platinum, mercury, lead all are natural resources actively recovered.

19. ? Read « Did You Know » on page 35. ?
Do you know of any other technologies we can use to reduce our impact?

20. Making the Connection
When humans interfere with their environment, it is often because they do not understand. In a country as large as Canada, it is difficult to imagine that a relatively small population can have a significant impact on the ecosystem.

21. Stuff Happens with Bill Nye: Breakfast (On Discovery Video) Time: 20:37