productivity in ecosystems Flashcards
(17 cards)
What is counted towards biomass of a plant?
The biological molecules that aren’t respired by the plants.
What is gross primary production?
The chemical energy store in biomass in a given area or volume in a given time.
What is net primary production?
The chemical in plant biomass after respiratory losses to the environment have been taken into account.
What is the equation involving both gross primary production and net primary production?
NPP = GPP - R
What are usually the units for primary production?
kJm -2 yr -1
Why is it not always advised to continually increase the temperature of glasshouses?
The rate of respiration may exceed the rate of photosynthesis decreasing the yield.
What is the equation for the net production of consumers?
N = I – (F + R)
What does N represent?
The net production of consumers.
What are usually the units for the net production of consumers?
kJm -2 yr -1
What does I represent?
The chemical energy store in ingested food.
What does F represent?
The chemical energy lost to the environment.
What does R represent?
The respiratory losses to the environment as heat.
What are saprobiotic decomposers?
Carries out extracellular digestion secreting out enzymes onto decaying matter and all the products have been taken up by active transport.
What is a food chain?
A straightforward feeding relationship from producers through to consumers.
What is the first trophic level?
Producers.
Why are apex predators so rare?
Energy is lost at each trophic level.
Why are food webs more accurate?
Food chains are not independent in an ecosystem.
