HMH Human Population Growth and the Environment

Which statement best describes Earth’s human carrying capacity?

• It is decreasing due to increasing population.

• It is decreasing due to decreasing death rates.

• It is a fixed number that we will soon exceed.

• It is increasing due to improved technology and medicine.

Refer to the graph. Predict what might happen to the world population after the year 2150. Choose the correct answer.

• It will grow rapidly.

• It will stop growing.

• It will decrease rapidly.

• It will not reach 9 billion.

Which statement is best supported by the graph? Choose the correct answer.

• The human population has never decreased in size.

• There were no humans on Earth around 6000 BCE.

• The human population is currently rising dramatically.

• An increase in the food supply was responsible for the increase in the population

Which of the following forms of energy is considered potentially renewable?

• biomass

• solar

• fresh water

• geothermal

What technique is used in industrial farming practices to help reduce soil erosion caused by rainfall?

• terracing ridges on sloped farmland

• minimizing introduced invasive species

• using less land to grow crops with higher yields

• removing field residue from the ground after a harvest

Engineers are developing a way to reduce runoff from roads by designing roads with more permeable surfaces. This allows water to slowly filter into the soil rather than running off into streams or rivers, carrying toxic chemicals with it. What is one way engineers could simulate this design solution in order to test it? Choose the correct answer.

• Repave a small section of a road, using several different materials.

• Use the new surface on only a few roads until results are measured.

• Develop a computer model of all the roads and the amount of traffic they receive.

• Use the new surface in a laboratory setting on a smaller scale and measure the permeability and runoff.

Which of the following is an example of nonpoint source pollution that can have adverse impacts on water quality? Choose the correct answer.

• A person throws old tires into a local pond to dispose of them.

• Acid rain forms in the sky and causes damage when it falls to the ground.

• A factory releases its wastewater into a pipe, which empties into a local stream.

• An auto body shop dumps waste oil and gas on a piece of ground behind the building.

A town is hoping to convert an old subsurface mining site into a regional park. What is one issue that the town must consider in order to ensure healthy biodiversity in the new park? Choose the correct answer.

• Rocks and soil must be put back in place.

• Air pollution must be monitored and minimized.

• Plants and animals must be brought in from other regions.

• Water must be carefully monitored and treated for pollution.

The graph shows the concentration of CO₂ in the atmosphere from 1860 to 1995, and the average temperature over the same period of time. Why is the information shown in this graph important?

• It shows that temperatures always fluctuate.

• It shows that global warming is linked to the greenhouse effect.

• It shows that the concentration of CO₂ in the atmosphere is not related to temperature.

• It suggests that the concentration of oxygen in the atmosphere has decreased since 1860.

According to the graph,           .

• the concentration of CO₂ in the atmosphere and the average global temperature have increased since 1980

• the concentration of CO₂ in the atmosphere and the average global temperature were the same in 1940

• the concentration of CO₂ in the atmosphere increased at the same steady rate from 1920 to 1980

• the average global temperature increased constantly from 1900 to 1950