NYS LE Human Impact Questions

Which occurrence most likely led to the other three?

• Human population growth reached 6.8 billion in 2010 and it continues to increase.

• The number of African elephants has declined from 1.2 million in 1979 to about 20,000 today.

• At one time, rain forests covered 14 percent of Earth and today they cover only 6 percent.

• Approximately 6,500 gallons of oil were spilled into a river in Illinois after a pipeline broke.

Many homeowners who used to collect, bag, and discard grass clippings are now using mulching lawnmowers, which cut up the clippings into very fine pieces and deposit them on the soil. The use of mulching lawnmowers contributes most directly to

• increasing the diversity of life

• recycling of nutrients

• the control of pathogens

• the production of new species

The graph shows data on the average life expectancy of humans. The change in life expectancy from 1910 to 1970 is most likely the result of

• an increase in poor land-use management that affected the quality of the topsoil

• the introduction of technology that had a negative impact on air quality

• a decrease in natural checks, such as disease, on the population

• . a widespread increase in the presence of lead and other heavy metals in water supplies

Fertilizers used to improve lawns and gardens may interfere with the equilibrium of an ecosystem because they

• cause mutations in all plants

• cannot be absorbed by roots

• can be carried into local water supplies

• cause atmospheric pollution

Which human activity would have the most direct impact on the oxygen-carbon dioxide cycle?

• reducing the rate of ecological succession

• decreasing the use of water

• destroying large forest areas

• enforcing laws that prevent the use of leaded gasoline

Car exhaust has been blamed for increasing the amount of carbon dioxide in the air. Some scientists believe this additional carbon dioxide in the air may cause

• global warming

• increased biodiversity

• habitat preservation

• ozone destruction

Which statement illustrates how human activities can most directly change the dynamic equilibrium of an ecosystem?

• A hurricane causes a stream to overflow its banks.

• Increased wind increases water evaporation from a plant.

• Water pollution causes a decrease in fish populations in a river.

• The ozone shield helps prevent harmful radiation from reaching the surface of Earth

Which human activity has probably contributed most to the acidification of lakes in the Adirondack region?

• passing environmental protection laws

• establishing reforestation projects in lumbered areas

• burning fossil fuels that produce air pollutants containing sulfur and nitrogen

• using pesticides for the control of insects that feed on trees

The creation of wildlife refuges and the enforcement of game laws are conservation measures that promote increased

• use of biocides

• preservation of species

• use of biological controls

• exploitation of species

Endangered peregrine falcons have been bred in captivity and released in area where they prey on pigeons and rodents. These activities are examples of

• species preservation and biological control

• overhunting and direct harvesting

• recycling and technological development

• conservation of resources and habitat destruction