Chapter 48 – Flashcards

In addition to burning fossil fuels, humans return CO2 to the atmosphere faster than it can be removed by:

Humans add about 150,000,000 tons of fixed nitrogen to the biosphere each year, primarily:

In the fall of 2012, Hurricane Sandy caused more than 110 deaths and an estimated $65.5 billion of damage along the Atlantic coast of the United States. Who needs to be involved in preparing for the next "Sandy"?

Nitrogen runoff leads to large increases in the populations of algae and cyanobacteria in lakes and oceans in a process known as ____________.

What is the one "low-tech" method we currently have available to actively remove carbon dioxide from the air?

There is a giant sequoia (Sequoiadendron giganteum) named Washington (after George Washington) that was believed to be the second largest tree in the world (253.7 ft in height!) until it was struck by lightning in 2003. The lightning strike caused a fire at the top of the tree that reduced Washington's height to about 229 feet. The fire released carbon that was sequestered in wood into the environment in the form of ____________.

What is the general effect of humans on the nitrogen (N) and phosphorus (P) cycles?

Oceans are about ____________ more acidic than they were in the 1960's.

About ____________ of the CO2 produced by humans during the past century has been absorbed by the ocean.

About how much of the nitrogen added to croplands ends up in food?

Wheat is a group of grass species. Cultivation originated in the eastern Mediterranean about 10,000 years ago. In comparison to closely related wild grasses, cultivated wheat has shorter stalks and fewer, larger seeds that are firmly attached to the stalk and are unable to disperse via wind like other grasses. Which of the following provides an explanation as to why wheat is so successful despite the loss of seed dispersal?

Wheat is a group of grass species. Cultivation originated in the eastern Mediterranean about 10,000 years ago. In comparison to closely related wild grasses, cultivated wheat has shorter stalks and fewer, larger seeds that are firmly attached to the stalk (e.g., they don't blow away in the wind). How do these changes affect the evolutionary fitness of wheat?

Clearcutting for grazing and croplands has destroyed more than ____________ of the pre-industrial area of tropical rainforest and, left unchecked, deforestation over the next century could eliminate ____________ of all tree species in the Amazon forest.

The manufacture of most fertilizer begins with nitrogen in the form of:

What pattern of growth are we currently exhibiting?

Energy use by individuals varies among countries primarily because of differences in:

Using records taken by Henry David Thoreau in the 1840's, scientists have documented what pattern of change in flowering plants around Boston, Massachusetts?

Amphibian population declines have been linked to:

Human impact on the nitrogen and phosphorus cycles happens primarily through our use of:

Giant sequoia trees (Sequoiadendron giganteum) are among the largest and longest-living organisms on Earth. These trees grow in weight by up to 1000 pounds of wood per year. As these trees are growing, they:

____________ of all amphibian species are threatened with extinction, and more than ____________ have undergone significant population declines in the last decade.