Essentials of Ecology

76 CHAPTER 3 Ecosystems: What Are They and How Do They Work?

LEARNING ONLINE

Log on to the Student Companion Site for this book at

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Chapter 3 for many study aids and ideas for further read-

ing and research. These include flash cards, practice quiz-

zing, Weblinks, information on Green Careers, and InfoTrac®

College Edition articles.

1. Calculate the per capita carbon footprint for each country
   and the world and complete the table.


2. It has been suggested that a sustainable average world-
   wide carbon footprint per person should be no more than
   2.0 metric tons per person per year (2.2 tons per person
   per year). How many times larger is the U.S. carbon foot-
   print per person than are (a) the sustainable level, and
   (b) the world average?

ECOLOGICAL FOOTPRINT ANALYSIS

Based on the following carbon dioxide emissions data and

2007 population data, answer the questions below.

Total

Carbon Footprint— Per Capita

Carbon Dioxide Emissions Population Carbon Footprint —

(in metric gigatons (in billions, Per Capita Carbon Dioxide

Country per year*) 2007) Emissions Per Year

China 5.0 (5.5) 1.3

India 1.3 (1.4) 1.1

Japan 1.3 (1.4) 0.13

Russia 1.5 (1.6) 1.14

United States 6.0 (6.6) 0.30

WORLD 29 (32) 6.6

Souce: Data from World Resources Institute and International Energy Agency

*The prefix giga stands for “1 billion.”

3. By what percentage will China, Japan, Russia, the United
   States, and the world each have to reduce their carbon
   footprints per person to achieve the estimated maximum
   sustainable carbon footprint per person of 2.0 metric tons
   (2.2 tons) per person per year?