Biodiversity—of genes, species, and ecosystems—is valuable in many ways.

• 16.1 Biodiversity can have many types of value.
• 16.2 This is how we do it: When 200,000 tons of methane disappears, how do you find it?
• 16.3 Biodiversity occurs at multiple levels.
• 16.4 Where is most biodiversity?

Extinction reduces biodiversity.

• 16.5 There are multiple causes of extinction.
• 16.6 We are in the midst of a mass extinction.

Human activities can have disruptive environmental impacts.

• 16.7 Some ecosystem disturbances are reversible, others are not.
• 16.8 Human activities can damage the environment: 1. Introduced non-native species may wipe out native organisms.
• 16.9 Human activities can damage the environment: 2. Acid rain harms forests and aquatic ecosystems.
• 16.10 Human activities can damage the environment: 3. The release of greenhouse gases can influence the global climate.
• 16.11 Human activities can damage the environment: 4. Deforestation of rain forests causes loss of species and the release of carbon.

We can develop strategies for effective conservation.

• 16.12 Reversing ozone layer depletion illustrates the power of good science, effective policymaking, and international cooperation.
• 16.13 With limited conservation resources, we must prioritize which species should be preserved.
• 16.14 There are multiple effective strategies for preserving biodiversity.