Human Impact 1

New fuels are being produced by converting corn and grasses into compounds containing alcohols that can be broken down for energy in various engines. The purpose of this research is to

•  reduce the use of nonrenewable resources.
• increase the rate of air pollution.
• reduce the rate of homeostasis in organisms.
•  cause a loss of biodiversity in the rain forests.

When fertilizers run off farmland into streams and ponds, the nitrogen content of the water increases. This can lead to rapid growth of algae in a process called eutrophication. How can this process affect other organisms in the water?

• Oxygen is used up as algae is decomposed, reducing the amount available to other organisms.
• The water becomes better able to support aerobic organisms.
• The algae provide food for fishes and other organisms, leading to decreased algae populations.
• The extra nitrogen provides additional food for the other organisms, increasing their population.

A strip mining company wants to lease some land that is currently part of a national park. They promise to reclaim the land should any minerals be mined from the area, and they are willing to pay top dollar for the rights. As an ecologist, what factors would you raise with the local government?

• the threat to local biodiversity
• management of the land after the company leaves
• the new jobs that would be created
• the increased traffic in the area

The diagram shows the carbon cycle.  If many trees are removed from a forest by logging, what is the most immediate effect on the carbon cycle in that forest?

•  increase in the rates of decomposition
• increase in the rates of atmospheric carbon dioxide
• decreased combustion of fossil fuel
•  increase production of organic compounds

1. Which of the following is not a renewable resource?

• coal

• wind energy

• solar energy

• water

1. What is one of the greatest threats to biodiversity on Earth?

• habitat destruction

• loss of drinking water

• decrease in food supply

• pollution

The primary cause of invasive species introduction is

• too much food

• human actions

• weather events

• asteroids

Why are fossil fuels a nonrenewable resource? 

• they take millions of years to replace 
• they can be used over and over again
• they are used to heat and light homes 
• they cause air and water pollution 

Converting solar energy into electricity may help slow down the depletion of which resource?

• copper

• sunlight

• water

• coal

Look at the diagram of a stream with toxic chemicals. The diagram models how toxic runoff can pollute a stream and also...

• create algae blooms.

• produce acid rain.

• pollute the groundwater.

• cause soil erosion.