ecology chapter 25

Which organism would most likely encounter the greatest difficulty in responding to climate change?

Select one:

a. A butterfly

b. A biennial shrub with animal-dispersed seeds

c. A long-lived tree

d. A rodent

c

Which statement about the global phosphorus cycle is true?

Select one:

a. It has a large atmospheric pool.

b. Because of the relatively high metabolic demand for phosphorus in the fixation of nitrogen gas, the rate of the nitrogen cycle is influenced by the availability of phosphorus.

c. Only a small fraction of the phosphorus transported from aquatic to terrestrial ecosystems is deposited in deep ocean sediments and lost.

d. The smallest pools of terrestrial phosphorus are found in soils.

b

A reduction in aerosols in the atmosphere would tend to _______ temperatures, because aerosols _______ sunlight.

Select one:

a. increase; reflect

b. increase; absorb

c. decrease; reflect

d. None of the above; a change in aerosol concentrations should not result in detectable climate change.

a

Before the Industrial Revolution, the flux of carbon from the terrestrial to the atmospheric pools _______ the flux in the opposite direction. Today, the flux of carbon from the terrestrial to atmospheric pools _______ the flux in the opposite direction.

Select one:

a. exceeded; exceeds

b. exceeded; is about equal to

c. was about equal to; exceeds

d. was about equal to; is less than

c

The largest pool of carbon can be found in

Select one:

a. the atmosphere.

b. sediments and rocks.

c. land surface, including soils and vegetation.

d. oceans.

b

Which statement about climate is false?

Select one:

a. Climate is the long-term description of weather, and encompasses not just average conditions but also the full scope of variation.

b. Climatic variation can occur only on very long time scales.

c. Changes in climate can have profound effects on ecological patterns and processes.

d. Climatic change refers to directional change in climate over a period of several decades.

b

Which statement about methane and global warming is false?

Select one:

a. On a per molecule basis, methane is a more potent greenhouse gas than carbon dioxide.

b. Livestock production contributes to methane emissions.

c. Atmospheric methane concentrations are much higher than they were before the industrial revolution.

d. Methane emissions are caused only by anthropogenic factors.

d

Which statement about ozone in the lower atmosphere is false?

Select one:

a. It is a greenhouse gas.

b. It can cause respiratory damage in humans.

c. It can damage the membranes of plants, thus potentially reducing their photosynthetic capacity.

d. It is not produced naturally and results only from anthropogenic activity.

d

Which statement about CFCs is false?

Select one:

a. They are largely inert in the stratosphere; their negative effect on ozone occurs because they react with other chemicals in the trophosphere to produce reactive chlorine molecules that destroy ozone.

b. They were originally developed for use as refrigerants.

c. They are not the only anthropogenic chemical that can destroy ozone.

d. Their atmospheric concentrations have been decreasing in recent years.

a

Select the greenhouse gas that fits the following description: Its concentration in the atmosphere has increased substantially over the last century; and while its total contribution to the greenhouse effect is only about 30% that of CO2, its contribution on a per molecule basis is greater that of CO2.

Select one:

a. Water vapor

b. Sulfur dioxide

c. Methane

c

Which statement about the nitrogen cycle is false?

Select one:

a. The nitrogen cycle is not linked to the carbon cycle.

b. Atmospheric nitrogen exists primarily in the unreactive dinitrogen gas form.

c. Despite their relatively small size, the land and ocean surface pools of nitrogen have very high biological activity.

d. Human activities have greatly altered the global nitrogen cycle.

a

Which statement regarding the oceanic pool of carbon is false?

Select one:

a. Most of the carbon is found in the deeper waters.

b. There is relatively little mixing between the ocean surface and the deeper waters.

c. CO2 dissolves in water due to a concentration gradient between the atmosphere (high concentration) and the ocean (low concentration).

d. The oceanic pool is the most stable of the major pools.

d

Which event would lead to enhanced atmospheric warming?

Select one:

a. Decreased anthropogenic emissions of SO2

b. Increased dust in association with land use change and desertification

c. A major volcanic eruption

d. Both b and c

a

Which statement about the global sulfur cycle is false?

Select one:

a. On a time scale of centuries, volcanic eruptions and dust from bare soils each account for approximately the same amount of sulfur that it is emitted into the atmosphere.

b. Sulfur is often a limiting factor for organismal growth.

c. Anthropogenic changes to the sulfur cycle have resulted in an increase in the pH of precipitation.

d. The major global pools are in terrestrial soils

b

Which of the following is not one of the currently documented ecological responses to climate change?

Select one:

a. Many species of nonmigratory European butterflies have shifted their ranges northward, with few shifting southward.

b. Migratory birds in England and North America have been arriving at nest sites later in the season.

c. There has been an upward shift from lower elevations to higher elevations of vascular plants in the European Alps.

d. Lizard populations have been going extinct.

b

According to the studies of Nemani and colleagues, global NPP _______ during the study period (1982-1999), with the largest increase documented in the _______.

Select one:

a. increased; tropics

b. increased; northern latitudes

c. decreased; southern latitudes

d. decreased; tropics

a

Between 1880 and 2012, the average annual global surface temperature

Select one:

a. decreased 0.8°C.

b. increased 0.2°C.

c. increased 0.8°C.

d. increased 2.0°C.

c

Which statement best describes our current understanding of the relationship between CO2 levels and photosynthetic activity?

Select one:

a. Increasing CO2 levels will result in a sustained increase in photosynthetic activity in both herbaceous plants and forest trees.

b. Increasing CO2 levels will result in a sustained decrease in photosynthetic activity in both herbaceous plants and forest trees.

c. Increases in photosynthesis rates due to increases in CO2 levels are likely to be short-lived for some herbaceous plants, but may be more sustained for forest trees.

d. Increases in photosynthesis rates due to increases in CO2 levels are likely to be short-lived for forest trees, but may be more sustained for some herbaceous plants.

c

In areas such as Vermont that have a seasonal snowpack, which of the following would likely be the most acidic?

Select one:

a. Precipitation that falls in late autumn

b. Snow that falls in December

c. The first meltwater of spring

d. Rains in May

c

DeLucia and colleagues have shown that increasing carbon dioxide has led to increased NPP in a pine forest. If this result can be generalized, it suggests that forests could be a _______ of anthropogenic carbon and thus tend to _______ the greenhouse effect.

Select one:

a. source; worsen

b. source; offset

c. sink; worsen

d. sink; offset

d

Why is there a net flow of carbon from the atmosphere to the oceans?

Select one:

a. The lower concentration of carbon dioxide in the oceans compared to the atmosphere leads to carbon dioxide diffusing into the oceans.

b. Plankton at the surface funnel carbon from the atmosphere to the ocean.

c. Carbon dioxide dissolves more readily in water than in the atmosphere.

d. Respiration from aquatic life lowers the carbon dioxide concentration in the oceans.

a

Which statement about deforestation is false?

Select one:

a. Before the mid-nineteenth century, the largest anthropogenic release of carbon into the atmosphere occurred via forest clearing.

b. Currently deforestation accounts for a negligible amount (less than 2%) of the anthropogenic release of carbon into the atmosphere.

c. Burning of forests releases CO2 as well as accelerating decomposition rates in forest soils.

d. Currently most deforestation is occurring in the tropics.

b

Increasing levels of carbon dioxide in the oceans make them _______ acidic. This change affects the ability of marine organisms to form protective shells made up of _______ carbonate.

Select one:

a. more; phosphorus

b. more; calcium

c. more; magnesium

d. less; calcium

b

The warming of Earth in recent decades has been most pronounced in

Select one:

a. and near Antarctica.

b. the tropics, just south of the equator.

c. the tropics, just north of the equator.

d. the mid-to-high latitudes of the Northern Hemisphere.

d