Question 1

As nitrogen input increases, _______ remains nearly constant at first and then increases rapidly at higher levels of nitrogen input.

Accepted Answer

A)  nitrogen mineralization 
B)  net primary productivity 
C)  leaf nitrogen concentration 
D)  NO3- leaching and soil acidification 
A)  nitrogen mineralization 
B)  net primary productivity 
C)  leaf nitrogen concentration 
D)  NO3- leaching and soil acidification

Question 2

In the absence of human activity, the net flux would be _______ Pg.

Accepted Answer

A)  ‒4 
B)  ‒3 
C)  1.7 
D)  4.7 
A)  ‒4 
B)  ‒3 
C)  1.7 
D)  4.7

Question 3

Refer to the figure.
  Which figure, based on the studies of grassland communities by Stevens, best describes the relationship of species diversity to varying levels of deposition of inorganic nitrogen?

Accepted Answer

A)  Figure A 
B)  Figure B 
C)  Figure C 
D)  Figure D 
A)  Figure A 
B)  Figure B 
C)  Figure C 
D)  Figure D

Question 4

Loss of stratospheric ozone has been most pronounced in

Accepted Answer

A)  the Arctic. 
B)  Northern Hemisphere temperate zones. 
C)  the tropics. 
D)  the Antarctic. 
A)  the Arctic. 
B)  Northern Hemisphere temperate zones. 
C)  the tropics. 
D)  the Antarctic.

Question 5

Which statement about the global sulfur cycle is false?

Accepted Answer

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. 
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.

Question 6

Which statement about climate is false?

Accepted Answer

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. 
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.

Question 7

Some of the more radical proposals to address and mitigate climate change involve geoengineering, which involves deliberately modifying Earth's climate. Evaluate how the actions listed would affect the global climate and global biogeochemical cycles by answering the questions that follow.
Option 1: Plant more trees.
Option 2: Build one or more giant reflective mirrors and send them into Earth's orbit.
Option 3: Fertilize ocean water with iron.
Option 4: Spray sulfuric acid as aerosol into the stratosphere.
-
Classify options 1-4 into two groups, based on the mechanisms by which they mitigate climate change. Which options would be most effective in changing atmospheric composition? Which options would be most effective in combating acid rain and ocean acidification?

Accepted Answer

The options can be classified as CO₂ remo

Question 8

Refer to the figure.
 
- This vegetation reconstruction shows major shifts in plant communities since the last glacial maximum 18,000 years ago. Why was there so much "No analog" community for much of the past 18,000 years?

Accepted Answer

A)  Species were evolving in response to changes in climate. 
B)  Thermal tolerance between plant species produced novel communities. 
C)  Unique climate conditions during the transition from the last glacial maxima produce unique plant communities. 
D)  Dispersal ability in response to a changing environment produced novel communities. 
A)  Species were evolving in response to changes in climate. 
B)  Thermal tolerance between plant species produced novel communities. 
C)  Unique climate conditions during the transition from the last glacial maxima produce unique plant communities. 
D)  Dispersal ability in response to a changing environment produced novel communities.

Question 9

Refer to the figure.
  Which figure best describes the relationship between carbon intake in oceans and pH of the oceans?

Accepted Answer

A)  Figure A 
B)  Figure B 
C)  Figure C 
D)  Figure D 
A)  Figure A 
B)  Figure B 
C)  Figure C 
D)  Figure D

Question 10

In eutrophic waters, algal growth is _______, leading to _______ decomposition rates and thus _______ levels of oxygen.

Accepted Answer

A)  increased; higher; higher 
B)  increased; higher; lower 
C)  increased; lower; lower 
D)  decreased; higher; higher 
A)  increased; higher; higher 
B)  increased; higher; lower 
C)  increased; lower; lower 
D)  decreased; higher; higher

Question 11

Aerosols are known to have a _______ effect on global temperatures. Some types of aerosols have increased in concentration recently, while others have decreased. One type of aerosol that has increased in concentration is the one associated with _______.

Accepted Answer

A)  warming; dust due to desertification 
B)  warming; increasing volcanic eruptions 
C)  cooling; dust due to desertification 
D)  cooling; anthropogenic nitrous oxide emissions 
A)  warming; dust due to desertification 
B)  warming; increasing volcanic eruptions 
C)  cooling; dust due to desertification 
D)  cooling; anthropogenic nitrous oxide emissions

Question 12

Which statement about CFCs is false?

Accepted Answer

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)  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.

Question 13

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

Accepted Answer

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. 
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.

Question 14

Refer to the figure.
  The figure shows the temperature (in °C, relative to modern temperature) and the concentrations of carbon dioxide (in ppm) and methane (in ppb) over the past 400,000 years.
- The current concentration of carbon dioxide is 404 ppm (not shown on the figure). Use the data in the figure to determine the highest carbon dioxide concentration levels that occurred over the past 400,000 years. At that point, the concentration of carbon dioxide was about _______% of the current concentration.

Accepted Answer

A)  45?50 
B)  55?60 
C)  70?75 
D)  90?95 
A)  45?50 
B)  55?60 
C)  70?75 
D)  90?95

As nitrogen input increases, _______ remains nearly constant at first and then increases rapidly at higher levels of nitrogen input.

In the absence of human activity, the net flux would be _______ Pg.

Refer to the figure. Which figure, based on the studies of grassland communities by Stevens, best describes the relationship of species diversity to varying levels of deposition of inorganic nitrogen?

Loss of stratospheric ozone has been most pronounced in

Which statement about the global sulfur cycle is false?

Which statement about climate is false?

Refer to the figure. - This vegetation reconstruction shows major shifts in plant communities since the last glacial maximum 18,000 years ago. Why was there so much "No analog" community for much of the past 18,000 years?

Refer to the figure. Which figure best describes the relationship between carbon intake in oceans and pH of the oceans?

In eutrophic waters, algal growth is ___, leading to _ decomposition rates and thus _____ levels of oxygen.

Aerosols are known to have a _ effect on global temperatures. Some types of aerosols have increased in concentration recently, while others have decreased. One type of aerosol that has increased in concentration is the one associated with _.

Which statement about CFCs is false?

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

The Web of Life

The Physical Environment

The Biosphere

Coping With Environmental Variation:

Coping With Environmental Variation: Energy

Evolution and Ecology

Life History

Behavioral Ecology

Population Distribution and Abundance

Population Dynamics

Population Growth and Regulation

Predation

Parasitism

Competition

Mutualism and Commensalism

The Nature of Communities

Change in Communities

Biogeography

Species Diversity in Communities

Production

Energy Flow and Food Webs

Nutrient Supply and Cycling

Conservation Biology

Landscape Ecology and Ecosystem Management

Filters

Exam 25: Global Ecology

As nitrogen input increases, _______ remains nearly constant at first and then increases rapidly at higher levels of nitrogen input.

In the absence of human activity, the net flux would be _______ Pg.

Refer to the figure. Which figure, based on the studies of grassland communities by Stevens, best describes the relationship of species diversity to varying levels of deposition of inorganic nitrogen?

Loss of stratospheric ozone has been most pronounced in

Which statement about the global sulfur cycle is false?

Which statement about climate is false?

Refer to the figure. - This vegetation reconstruction shows major shifts in plant communities since the last glacial maximum 18,000 years ago. Why was there so much "No analog" community for much of the past 18,000 years?

Refer to the figure. Which figure best describes the relationship between carbon intake in oceans and pH of the oceans?

In eutrophic waters, algal growth is _______, leading to _______ decomposition rates and thus _______ levels of oxygen.

Aerosols are known to have a _______ effect on global temperatures. Some types of aerosols have increased in concentration recently, while others have decreased. One type of aerosol that has increased in concentration is the one associated with _______.

Which statement about CFCs is false?

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

The Web of Life

The Physical Environment

The Biosphere

Coping With Environmental Variation:

Coping With Environmental Variation: Energy

Evolution and Ecology

Life History

Behavioral Ecology

Population Distribution and Abundance

Population Dynamics

Population Growth and Regulation

Predation

Parasitism

Competition

Mutualism and Commensalism

The Nature of Communities

Change in Communities

Biogeography

Species Diversity in Communities

Production

Energy Flow and Food Webs

Nutrient Supply and Cycling

Conservation Biology

Landscape Ecology and Ecosystem Management

Filters

In eutrophic waters, algal growth is ___, leading to _ decomposition rates and thus _____ levels of oxygen.

Aerosols are known to have a _ effect on global temperatures. Some types of aerosols have increased in concentration recently, while others have decreased. One type of aerosol that has increased in concentration is the one associated with _.