energy Flashcards
What are producers?
= plants, able to produce their own carbohydrates, using co2 and water
What happens between each trophic level?
= majority of energy is lost due to respiration and excretion
= the remaining is used to form biomass
=
What 2 ways can biomass be measured?
= the amount of biomass remaining in an organism can be measured in terms of:
= mass of carbon
= dry mas of tissue given per given area, as water cannot be measured as this ma change depending on the season
How to work our viomass of plamt?
= remove all of the water, and heat up,weigh until it is constant
What does productivity of an ecosystem depend on?
= abiotic and biotic factors
What is gross primary production GPP?
= chemical energy stored in plant biomass, given per area or per volume
= it is the total energy resulting from photosynthesis
What is npp net primary production?
= chemical energy store in plant biomass, taking into account, energy is lost in respiration,
NPP= GPP-R
= so minimise respiration value
=
What is NPP needed for?
= biomass
= biomass can be passed onto next trophic level in a food web
= energy left over, that is avaliable to the plant to create new biomass, and pass onto trophic level
How to calculate the net production of consumers?
N= I-(F+R)
I= ingested food
R: lost in respiration
F: lost in faeces and urine
N: new biomass made
What are the rates of productivitu?
= compare how productive an ecosustem are
= kj per m^2 or
What are the units of energy?
= Kj for energy
What is respiratory losses?
= not all of the energy is passed onto the trophic levels, some is lost as organisms grows, move, respire, or indigestble matter
= ATP being formed from respiration
Where can light energy be lost due to?
= reflected off the leaf
= tranmission: misses contact with any chlorophyll
= incorrect wavelength of light, green light
What is the unit for biomass?
gm^-2
Why is such little amount of energy passed between trophic levels?
= not all of the organism may be consumed, plants roots bones
= some of the organism is indigestible, fur, cellulose
= heat loss from respiration
= energy lost by excretion-urine from faeces
=
Why does the amount of biomass decrease as we move along trophic levels?
= due to less energy being avalaible to produce the biomass
Why do food chains usually contain 4 to 5 trophic levels?
= flow of energy between trophic levels are ineffcient
= less energy by the time of the triohic levels
How is effiency of energy transfer measured?
= energy avaliable after transfer/energy avaiale before the transfer x 100
If they want an example for the unit of biomass what can you give?
= kJ ha–1 year–1.
