ECOSYSTEMS AND CONSERVATION ECOLOGY

Question 1

What is an ecosystem?

Answer 1

An ecosystem consists of all the organisms living in a given area and the abiotic factors with which they interact

Question 2

What are detrivores?

Answer 2

Detrivores are decomposers, which are heterotrophs that derive their energy from detritus (nonliving organic matter)

Question 3

What trophic levels do decomposition connect?

Answer 3

Decomposition connects to all trophic levels

Question 4

How does energy flow in ecosystems?

Answer 4

Energy flows through ecosystems

Question 5

How do chemicals cycle in ecosystems?

Answer 5

Chemicals cycle within ecosystems

Question 6

What is gross primary product (GPP)?

Answer 6

GPP is the total primary production in an ecosystem

Question 7

What are the most productive ecosystems per unit area?

Answer 7

1. Tropical rain forests
2. Estuaries
3. Coral reefs

Question 8

How does size matter in GPP?

Answer 8

Marine ecosystems are relatively unproductive per unit area, but contribute much to global net primary production because of their area

Question 9

What is net primary production (NPP)?

Answer 9

NPP is GPP minus the energy used by autotrophs for respiration and is the amount of new biomass added in a given period of time

Question 10

Primary production in terrestrial ecosystems general increases with what?

Answer 10

1. Temprature
2. Moisture (precipitation)
3. Solar energy

Question 11

What is the most common limiting nutrient in terrestrial ecosystems?

Answer 11

Nitrogen

Question 12

Where is phosphorus a limiiting nutrient?

Answer 12

Older soils

Question 13

How does carbon cycle between ecosystem reservoirs?

Answer 13

Carbon moves from producers to consumers

Question 14

What controls primary production in marine and freshwater ecosystems?

Answer 14

Light and nutrients

Question 15

What nutrients are most often limiting primary production in marine ecosystems?

Answer 15

Nitrogen and phosphorus

Question 16

What regulates nutrient cycling?

Answer 16

1. Vegetation
   
   1. Retains nutrients
2. Decomposition
   
   1. Releases nutrients by recycling vegetation

Question 17

What is the main control of nutrient loss in a forest ecosystem?

Answer 17

Plants

Question 18

What are the 3 levels of biodiversity?

Answer 18

1. Genetic diversity in a population
2. Species diversity in an ecosystem
3. Community and ecosystem diversity across the landscape of an entire region

Question 19

What are the 4 major threats to biodiversity?

Answer 19

1. Habitat destruction
2. Introduced species
3. Overexploitation of resources
4. Disruption of “interspecies interactions”

Question 20

How does the human population disrupt chemical cycles?

Answer 20

1. Agriculture and nitrogen cycling - removes soil nutrients
2. Contamination of aquatic ecosystems - excess algae growth caused by runoff
3. Acid precipitation - combustion of fossil fules
4. Toxins in environment
5. Greenhouse effect and global warming - rising of atmospheric CO2 levels and methane
6. Depletion of atmospheric ozone - allows more UV penetration

Question 21

What is the extinction vortex?

Answer 21

The extinction vortex is the downward spiral of population decline unique to small populations

Question 22

What is the key factor driving the extinction vortex?

Answer 22

The loss of genetic diversity

Question 23

What does a loss in genetic variability lead to?

Answer 23

Less ability to adapt to changes

Question 24

If an organism is unable to adapt to changes, what happens?

Answer 24

Reproductive success and fitness are lowered, increasing mortality

Question 25

What happens when mortality increases in small populations?

Answer 25

They grow progressively smaller until they are gone forever

Question 26

What is bioremediation?

Answer 26

Bioremediation is the use of living organisms to detoxify ecosystems

Question 27

What is augmentation?

Answer 27

Augmentation is the use of organisms to add essential materials back to a degraded ecosystems