6.1A Changing Landscape

Name Class Date

6.1A Changing Landscape

The Effect of Human ActivityHumans and other organisms change the environment when they obtain food, eliminate wastes, and prepare places to live.

Because Earth is like an island, life is limited to the resources that are here.

Humans affect regional and global environments through three major activities:

• ______, particularly______, which is the cultivation of a single crop
• ______, including conversion of farmland and destruction of habitats for other organisms
• ______, which consumes energy and emits pollutants

Sustainable DevelopmentIn economic terms, ecosystems are providers of goods and services (natural resources).

Healthy ecosystems produce or replace ______.

Humans must be careful about the use of ______, such as ______, which cannot be replaced.

______provides for human needs while preserving the ecosystems that provide renewable resources.

The Effect of Human Activity

How is Earth like an island?

Sustainable Development

1. Sustainable development is the wise use of .

renewable resourcesnonrenewable resourcesboth renewable and nonrenewable resources

2. When fossil fuels are depleted, they are essentially gone .

for a little whileforever

3. A cannot be produced within a reasonable amount of time.

renewable resourcenonrenewable resource

4. Which of the following is an example of sustainable development? Circle the right answer.

When building a new house, the builders leave many of the trees in place.

After they paint a building, the painters dump the leftover paint in a nearby stream.

A new highway goes through a wetland.

6.2 Using Resources Wisely

Soil Resources Soil is a ______, but it must be managed properly.

______is the wearing away of surface soil by water and wind.

In dry climates, farming and overgrazing change farmland into deserts, a process called ______.

______is loss of forests. Because healthy forests hold soil in place, deforestation increases erosion.

Sustainable uses include leaving stems and roots of previous crops in place, ______, contour plowing, terracing, selectively harvesting mature trees, and ______.

Freshwater Resources The amount of fresh water is limited, and some sources cannot be replaced.

A ______ is a harmful material that can enter the biosphere. Water pollutants come from industrial chemicals, residential sewage, and other sources.

Nonpoint pollution-

______

Point pollution-

______

Many chemical pollutants become concentrated in organisms at higher trophic levels of the food chain through ______.

Sustainable uses include conservation, pollution control, and watershed protection.

Atmospheric ResourcesClean air is important to human health and Earth’s climate. Pollution reduces air quality.

______is a mixture of chemicals formed from emissions from cars and industry.

Burning fossil fuels releases compounds that join with water in air, forming ______.

______, such as ______and ______, can cause global warming.

Particulates are microscopic particles that cause health problems.

One way of sustaining air quality is controlling automobile emissions.

Soil Resources

What is topsoil? How does it form?

What is a “dead zone,”and what is its cause?

Atmospheric Resources

1.Which is the name for the mixture of chemicals that forms as a gray-brown haze in the atmosphere?

A.dustC.ozone

B.smogD.radiation

2.Which component of acid rain kills plants and harms soil?

A.carbon dioxide and waterC.nitric and sulfuric acids

B.CFCs and fossil fuelsD.ozone and particulates

3.Which is the name for the bits of ash and dust put into the air by certain kinds of diesel engines?

A.particulatesC.ozone layer

B.precipitationD.greenhouse gases

4.Which is a pollutant of soil and water that is now dropping steadily due to laws that affected the automobile industry?

A.carbonC.nitrogen

B.leadD.ozone

5. Why is smog a problem?

Biological MagnificationThe diagram below shows the biological magnification of the pollutant DDT.

1. Find the trophic level with the lowest

concentration of DDT. Color it blue.

1. Find the trophic level with the highest

concentration of DDT. Color it red.

1. Draw an arrow showing how the

concentration of DDT increases in

trophic levels.

Use the diagram to answer the questions.

4.Circle the organism that has the most DDT in its body.

zooplanktonsmall fish

5.Think about your answer to item 4. Select the choice below that best explains thereasoning behind your answer.

A.Zooplankton has DDT. Small fish eat lots of zooplankton. Therefore DDT builds up in

the bodies of the small fish.

B.Large fish eat small fish, and large fish have more DDT than small fish. Therefore

small fish have the most DDT.

Concept Map

6.3 Biodiversity

The Value of Biodiversity The sum of all the genetic diversity among all the organisms in the biosphere is called ______. There are three general types of biodiversity:

______is the variety of habitats, communities, and ecological processes in the biosphere.

______is the number of different species in an area or in the biosphere.

______is the total of all genetic information carried in living things.

Biodiversity benefits humans through its contributions to medicine and agriculture and through the provision of ecological goods and services.

Threats to Biodiversity Human activities threaten biodiversity.

Development splits ecosystems into pieces, resulting in ______. The smaller the pieces of a habitat, the less likely that species in the habitat can survive.

Other threats to biodiversity include hunting, introduced species, pollution, and climate change.

Conserving Biodiversity Conservation efforts are focused on three things:

______is the focus of groups such as the Association of Zoos and Aquariums (AZA), which oversees species survival plans (SSPs).

______is the main thrust of global efforts. Biologists are particularly concerned about ______, which are places where significant numbers of habitats and species are in immediate danger of extinction.

______is part of developing plans to replace harmful activities with ones that conserve environments and biodiversity.

Threats to Biodiversity

• The current rate of species loss is ______times the typical rate of extinction.
• Habitat fragmentation ______the impact of hunting on endangered species.
• ______species can become invasive and threaten biodiversity.
• The increased concentration of carbon dioxide in air is making oceans ______and putting stress on coral reefs.

What are five ways that human activity reduces biodiversity?

Identify three reasons why endangered species are hunted.

6.4 Meeting Ecological Challenges

Ecological Footprints The ______of an individual or a population is the amount of land and water needed to provide resources, absorb wastes, and render the wastes harmless.

Ecological Footprints

Explain this statement: The average American has an ecological footprint more than four times larger than the global average.

Ecology in Action

Case Study 1: Atmospheric Ozone

The ozone layer is a high concentration of ozone at aboutabove Earth’s surface.

The ozone layer is important to humans because it protects against exposure to ______from the sun. UV radiation causes______,damages eyes, and reduces resistance to disease.

Case Study 2: North Atlantic Fisheries

Technologies that have led to large increases in the mass of ocean fish caught include large boats and high-tech equipment. ______caused the decline in fish catches since 1997. An alternative to commercial fishing is______,which produces large amounts of food with minimal environmental damage if properly managed.

Case Study 3: Climate Change

How does the change in global temperature between 1850 and 2000 compare with the change that occurred between 1850 and 1880?

List three factors that may have contributed to the trend shown in the graph.

Suggest three possible effects of global warming on the future of the biosphere.