Human Impacts on the Environment

1. Human Impacts on the Environment

2. A Changing Landscape • The Earth is an island of sorts – our resources are limited. • We must learn to live within our limited resources for our survival is at stake.

3. Human Activities • Humans are part of ecological systems. • Humans depend on ecosystem goods and services for survival needs. • Ecosystem goods and services like storage and recycling of nutrients. • Human activities can change our local and global environments.

4. Human activities that affect the biosphere • Hunting and gathering • Agriculture • Industry • Urban Development

5. Hunting and Gathering • Humans obtain food by hunting and gathering. • Subsistence hunter hunts only for the food he needs for the table. • Depends on the animal and plant resources for survival. • People do not make many demands on the environment, but most use some sort of technology like guns or manufactured tools.

6. Agriculture • Agriculture provided humans with a dependable supply of food. • Agriculture changed the landscape because humans now gathered in larger settlements rather than traveling in small groups in search for food. • Stable communities lead to the development of the elements of civilization like government, laws and writing.

7. From traditional to modern agriculture • Farmers acquired machinery to help with cultivation. • Farming developed and lead to an exchange of crops globally. • Science and technology lead to changes in farming: - irrigation allowed more land for farming - machinery allowed more higher crop yields - new varieties of crops are developed - monoculture practices became common

8. From traditional to modern agriculture • The Green Revolution increased the world’s food supply • Includes: • Modern machinery to plant more effectively • Using chemicals for fertilizers • Using monoculture (large fields of one kind of crop)

9. Challenges for the future of world food supplies • Monoculture farming leads to problems with insect pests and diseases. • Chemical pesticides can damage beneficial insects, contaminate water supplies, and accumulate in the environment. • Finding enough water for irrigation of the fields

10. Industrial Growth and Development • Industrial Revolution added machines and factories to civilization. • The combination of science and technology and industrial productivity is responsible for the modern conveniences that we enjoy. • Waste was discarded into air, water and soil. • Populations grew and humans moved out of the cities into the suburbs.

11. Industrial Growth and Development • Ecologists voice the following concerns: • Industry pollutes air, water and soil • Dense populations produce wastes • Suburban growth consumes farmland and natural habitats • Stresses are placed on; • plant and animal populations • the biosphere’s life-support systems

12. Key Concepts • Three activities that affect the biosphere: • Agriculture • Industry • Urban development • Three resources humans depend upon for survival: • Breathable air • Drinkable water • Fertile soil

13. Quick Quiz • What are the three major impacts on the environment?