Using Resources Wisely

Learning Objectives Describe how human activities affect soil and land. Describe how human activities affect water resources. Describe how human activities affect air resources.

Soil Resources

Healthy soil supports both agriculture and forestry.

The mineral- andnutrient-rich portion of soil is called .topsoil

Soil Erosion

Erosion is the removal of soil by water or wind.

The process of turning farmland into desert is called

________________.desertification

Deforestation

Healthy forests:•protect fresh water•absorb carbon dioxide•moderate climate

, or loss of forests, can have negative effects on soil quality.

Deforestation

Soil Use and Sustainability

Best practices in agriculture and forestry:

•leaving stems and roots

•crop rotation

•contour plowing

•terracing

•selective harvesting

Freshwater Resources

Fresh water is considered a renewable resource, but supplies are limited.

The Ogallala aquifer is expected to run dry within decades.

Water Pollution

• Industrial and agricultural

chemicals

• Residential sewage

• Nonpoint sources

Water

Producers

1

1,000

10,000

100,000

1,000,000

10,000,000

Zooplankton

Small fish

Large fish

Fish-eating birds

Water Pollution

Water

Producers

1

1,000

10,000

100,000

1,000,000

10,000,000

Zooplankton

Small fish

Large fish

Fish-eating birds

In a food chain, the concentration of a pollutant as the number of organisms at a trophic level .

increases

decreases

Water Quality and Sustainability

Preserve ecosystems to protect watersheds

Conserve water

Atmospheric Resources and Pollutants

• Smog• Acid rain• Greenhouse gases• Particulates

Air Pollution: Acid Rain

Formed by the chemical transformation of nitrogen and sulfur

Statues and buildings Plant life

Air Quality and Sustainability

Automobile emission standards and clean-air regulations have improved air quality in some regions.

Overview

• Healthy supports both agriculture and forestry.

• Best practices can minimize soil .

• The primary sources of water pollution are:

industrial and agricultural chemicals

residential sewage

nonpoint sources

soil

erosion