Ecotsystem Ecology

Question 1

Primary producers allow energy to be….

Answer 1

Available to all species in the ecosystem

Question 2

Why are plants measured by dry mass

Answer 2

Because once you cut the leaf the water is lost

Question 3

Primary production

Answer 3

The conversion of inorganic material into organic material

Question 4

Gross primary production

Answer 4

Total primary production

The rate at which energy is captured and assimilated by producers in a given area

GPP=PP

Question 5

Net primary production

Answer 5

NPP=GPP-R

R=respiration

PP available to consumers

The rate at which energy is assimilated by producers and converted into producer biomass in a given area

Question 6

Standing crop

Answer 6

The bodies/biomass of the living organisms within a unit of area

Question 7

Biomass

Answer 7

Mass of organisms per unit area of ground or volume of water

Question 8

Initial mass and final mass of leaves left in light and in dark

Answer 8

More initial mass in dark (carbon dioxide lost)

More final mass in light (carbons dioxide used to make photosynthetic products)

Question 9

What percent of NPP is the total solar energy

Answer 9

1% of solar input becomes biomass

Question 10

PP is affected by what factors

Answer 10

-geographic range
-water
-nutrient levels
-temperature
-photosynthetic efficiency
-vegetative cover
-length of growing season

Question 11

Lieberg law of minimum

Answer 11

The rate of any biological process is limited by the factor in the least amount relative to requirements for that process

Question 12

Where is the greatest rate of PP in oceans

Answer 12

Coastlines

-upwelling of nutrients

Question 13

What does adding nitrate and phosphate do to primary production of algae

Answer 13

Increases it but varies by site

Helps a bit but not much (not as limiting)

Question 14

The more nitrogen you add, phosphorous becomes _____

The more phosphorous you add, nitrogen becomes _____

Answer 14

Limiting factor

Limiting factor

Question 15

How limiting are nitrogen and phosphorus in terrestrial, freshwater and marine ecosystems

Answer 15

-N and P are limited equally
-same as above

-N is more limiting

Question 16

What ecosystem has the most primary production

Answer 16

Swamps and marshes

Question 17

Two laws of thermodynamics

Answer 17

-total amount of energy in the universe is constant (can’t be created or destroyed, only transferred)
-heat energy moves from warmer body to colder one

Question 18

_____ increases over time in a closed system

Answer 18

Entropy (amount of disorder)

Question 19

Trophic level

Answer 19

Position on the food web determines by the number of transfers of energy from primary producers

Question 20

__________ limit the number of trophic levels in an ecosystem

Answer 20

Energy losses

Question 21

As energy is transferred from one trophic level to another, there are losses:

Answer 21

-Incomplete consumption
-incomplete assimilation
-respiration by consumers
-heat production

Question 22

Terrestrial vs aquatic ecosystems biomass

Answer 22

Terrestrials have lots of producers and smaller tertiary consumers

Aquatic has smaller amount of producers that feed a massive biomass of consumers

Question 23

Terrestrial PP is limited by

Answer 23

Temperature and moisture

Question 24

Aquatic PP is limited by

Answer 24

Nutrient availability

Question 25

Green food web

Answer 25

A food web focussed on how the producers obtain energy from photosynthesis and how this energy moves up the food web when producers are consumed.

Question 26

Brown food web

Answer 26

Focussed on how scavengers, Derrick red and decomposers obtain energy from dead organic matter and how this energy moves up the food web when they are consumed

Question 27

Egested energy

Assimilated energy

Answer 27

The portion of consumed energy that is excreted or regurgitated

The portion of consumed energy digested and absorbed

Question 28

Respired energy

Answer 28

The portion of consumed energy used for respiration

Question 29

Net secondary productivity

Answer 29

The rate of consumer biomass accumulation in a given area

Question 30

Increase in_____ leads to an increase in NPP

Answer 30

Annual temperature

Question 31

Consumption efficiency

Answer 31

The percentage of energy or biomass in a trophic level that is consumed by the next higher trophic level

CE=Consumed energy/net production of energy of the next lower trophic level

Question 32

Assimilation efficiency

Answer 32

The percentage of consumed energy that is assimilated

AE=assimilated energy/consumed energy

Question 33

Net production efficiency

Answer 33

The percentage of assimilated energy that is used for growth and reproduction

Net production efficiency=net production energy/assimilated energy

Question 34

Ecological efficiency or food chain efficiency

Answer 34

Net production energy of a trophic level/net production energy of the next lower trophic level

The percentage of net production from one trophic level compared to the next lower trophic level

Question 35

Which ecosystem typically has more trophic levels

Answer 35

Aquatic

Question 36

Residence time

Answer 36

The length of time that energy remains in a given trophic level

Question 37

Ecological stoichiometry

Answer 37

The study of the balance of nutrients in ecological interactions, such as between a herbivore and a plant