Chapter 6 Section 1 A Changing Landscape Objective: Describe human activities that can affect the biosphere

Opener On the top of a lined piece of paper write “A Changing Landscape” List as many human activities as you can that you think have affected the biosphere

Earth as an Island All of the organisms - including humans - that live on Earth share a limited resource base and depend on it for their long-term survival.

Human Activities Humans depend on the ecosystem for goods and services: breathable air drinkable water fertile soil that supports farming Humans have become the most important source of environmental change on the planet.

Human Activities Among human activities that affect the biosphere are hunting and gathering, agriculture, industry, and urban development. (KEY CONCEPT)

Hunting and Gathering For most of human history, our ancestors obtained food by hunting and gathering. Some scientists hypothesize that the first humans to arrive in North America caused a major mass extinction of animals. Today groups of people in scattered parts of the world, from the Arctic to Central Africa, still follow the hunter-gather way of life to some degree.

Agriculture Agriculture = the practice of farming The spread of agriculture was among the most important developments in human history. It provides human societies with a fundamental need: a dependable supply of food that can be produced in large quantity and stored for later use.

From Traditional to Modern Agriculture In the 1800s and 1900s, advances in science and technology set the stage for a remarkable change in agriculture: irrigation in dry areas machinery for plowing, planting, and harvesting new varieties of crops that produce higher yields chemical fertilizers that boost plant growth pesticides controlled crop damaging insects

The Green Revolution green revolution = the development of highly productive crop strains and the use of modern agricultural techniques to increase yields of food crops This was introduced because by the middle of the twentieth century, despite agricultural advances, there were food shortages in many parts of the world.

Challenges for the Future Challenge #1: large scale monoculture (large fields are planted with a single variety year after year) can lead to problems with insect pests and diseases. Challenge #2: Finding enough water for irrigation.

Industrial Growth and Urban Development Industrial Revolution Pros: provided us with - machines and factories homes clothes electronic devices farm-machinery automobiles

Industrial Growth and Urban Development Industrial Revolution Cons: pollution of the air, water, and soil dense human communities produce wastes that must be disposed of suburban growth consumes farmland and natural habitats can place additional stress on plant and animal populations and on the biosphere’s life-support systems

6-1 Section Assessment List three types of human activities that can affect the biosphere. For each activity, give one environmental cost and one benefit. Identify three of Earth’s resources on which humans and other organisms depend for the long-term survival of their species. What did agriculture provide that changed the course of human history? Identify two ways in which the Industrial Revolution has affected living things.