Ch 2 - Gaia hypothesis

Question 1

who is Gaia?

Answer 1

Titan of the Earth (Greek mythology)
Hypothesis: Earth is a living entity that regulates itself like our bodies do.
*does homeostasis.

Question 2

1. Productivity
2. What ecosystems have the highest productivity to the lowest productivity?

Answer 2

1. Activity of producers in different biomes/ecosystems.
2. Algal beds/reefs, tropical rainforests, swamps, open ocean, tundra, desert scrub, extreme rock/snow.

Question 3

Human impact on carbon/oxygen cycle

Answer 3

Increase in CO2 due to human activity -> accelerated greenhouse effect because of accelerating in rapid cycling of carbon.
*fossil fuels generate electricity.

Question 4

Human impact on nitrogen cycle

Answer 4

• Excess fertilizers lead to algal blooms.
• repeated crops reduce nitrogen from the soil.

Question 5

Human impact on sulfer cycle

Answer 5

Human-made sulfur emissions increase acid rain. (Imbalance created)

Question 6

Human impact on phosphorus cycle

Answer 6

Excess fertilizers lead to algal blooms.

Question 7

What is the percentage of CO2, N2, and O2 in our current atmosphere?

Answer 7

CO2 = 0.03%
N2 = 78%
O2 = 21%
(producers are ONLY capable of making O2)

Question 8

What is the percentage of CO2, N2, and O2 in a hypothetical atmosphere with no life?

Answer 8

CO2 = 98%
N2 = 1%
O2 = 0% (no producers)